Operation and Maintenance Manual for MALAMPUZHA DAM

O & M Mannual for Malampuzha Dam August 2020 AU

1

Operation and Maintenance

Manual for

MALAMPUZHA DAM (KL07HH0003)

Kerala Water Resources Department

State Of Kerala

August 2020 O&M Manual of Malampuzha Dam

i

Operation and Maintenance Manual for

Malampuzha Dam

(Prepared By)

KERALA WATER RESOURCES DEPARTMENT

STATE OF KERALA

August 2020


ii

Government of Kerala

Operation and Maintenance Manual

Malampuzha Dam


iii

PREFACE The Malampuzha Irrigation Project is the first large scale Irrigation system attempted

in the Malabar District of old Madras State. . It comprises the construction of a Dam across the Malampuzha river at a place about 8 Km north east of Palakkad junction Railway station of Southern Railway in Palakkad District. The aim of Malampuzha Project was not only to bring new lands to cultivation, but also to supplement the rainfall in the season between the South West and North East monsoon in December andJanuary.

The project constructed in erstwhile Madras State and was commissioned in 1955 before formation of Kerala state. At present designated ayacut under Malampuzha Project is 21165 Ha. The project has now become an integral part of the lives of the people of Palakkad Taluk and its surroundings, since it is the main source of water for agricultural and drinking purpose.

The dam consists of a straightly gravity masonry dam across Malampuzha river having a length of main dam 1133.85 m and a height 38.1 m and 2 nos saddle dam (length PQ 100.58 m, RS 392.27 m) and earthen dam ( length 222.2 m) of total length of masonry dam 1626.71 m . The spill way has length of 56.70 m with four vertical lift type gates and four sluice for left(3) and right ( 1) bank canals . The storage capacity of the reservoir is 226.00 Mm3 with a design spill way capacity of 849.5cumecs.

This Operation and Maintenance (O&M) Manual for Malampuzha Dam is a detailed set of written descriptions of step-by-step procedures for ensuring that the dam is safely operated and properly maintained. Timely inspection and maintenance is necessary for the safe functioning of the dam and continued productive use of the dam and reservoir. The term “O&M” as employed in this manual includes operation, inspection, maintenance and repair of dam components, replacement of equipment and appurtenant structures, asrequired.

This manual is provided to assist the dam owner in management of their project in a safe and efficient manner. The Dam Safety Bill, 2010, introduced in the Lok Sabha on August 30, 2010, and subsequently referred to the Parliamentary Standing Committee on Water Resources for examination, prompted the need for updated procedures for dam owners to follow during day to day, 24/7 operation of their respective dams. The draft Dam Safety Bill requires State Dam Safety Organizations (SDSO) to keep perpetual vigilance, carry out inspections regularly, and monitor the operation and maintenance of all dams in order to ensure their safe functioning. Where a SDSO does not exist, the National Committee on Dam Safety acting through the Central Dam Safety Organisation is required to carry out theseactivities.

This manual was prepared following the guidelines published by DRIP, CWC.


iv

LIST OF ACRONYMS

The following acronyms are used in this publication:

AAR Alkali-AggregateReaction

ACI American ConcreteInstitute

ASTM American Society for TestingMaterials

CDSO Central Dam SafetyOrganization

CWC Central Water Commission

CWPRS Central Water and Power Research Station

DDMA District Disaster Management Authority

DHARMA Dam Health and RehabilitationMonitoring

Application

DRIP Dam Rehabilitation and Improvement Project

EAP Emergency ActionPlan

IS Indian Standard

KERI Kerala Engineering ResearchInstitute

KDSA Kerala Dam Safety Authority

KSEBLtd Kerala State Electricity Board Ltd

KWA Kerala WaterAuthority

NCDS National Committee on DamSafety

NCSDP National Committee on Seismic Design Parameters

PMF Probable Maximum Flood

PMP Probable MaximumPrecipitation

RCC Reinforced CementConcrete

DSO State Dam SafetyOrganization

USBR United States Bureau of Reclamation


v

CONTENTS Page

1 General Information 1 1.1 Purpose, Location, Description of dam 1 1.2 Assignment of responsible officials 10 1.3 Collection & Reporting of Dam and Reservoir Data 13 1.4 Public Utilities and Safety 17 1.5 Restricted Areas 17 1.6 Staff position, Communication & Warning System 18 1.7 Distribution of Operation & Maintenance Manuals 21 1.8 Supporting Documents & Reference Manual 21 1.9 Typical Schedule of Duties 22 2 Project Operation 26 2.1 Basic data 26 2.2 Operation Plan 54 2.3 Normal Operation 54

2.3.1 Instructions for Operating Control Mechanisms 54 2.3.2 Operation of the Reservoir 55 2.3.3 Safety Aspects 56 2.3.4 Flood Release Procedure 56 2.3.5 Reservoir Capacities 57 2.3.6 Inflow forecasting 57

2.4 Emergency Operation 57 2.5 Drawdown facility 59 2.6 Initial filling of reservoir 59 2.7 Record keeping 59 3 PROJECT INSPECTION 61 3.1 Types of Inspections 61 3.2 Informal Inspections 61 3.3 Scheduled Inspections 62 3.4 Special (Unscheduled) Inspections 62 3.5 Comprehensive Evaluation Inspections 63

3.5.1 General. 63 3.5.2 Details to be provided to DSRP before inspection 63 3.5.3 Field Inspection – Observations & Recommendations regarding

Remedial Measures 65

3.5.4 Components involved 67 4 PROJECT MAINTENANCE 68 4.1 Maintenance Plan 68 4.2 Maintenance Priorities 68

4.2.1 Immediate Maintenance 68 4.2.2 Preventive Maintenance 69

4.3 Maintenance Items 70 4.3.1 Earthwork 70 4.3.2 Upstream Riprap 72


vi

4.3.3 Controlling Vegetation 72 4.3.4 Controlling Animal Damage 73 4.3.5 Controlling Ants and Termites (White Ants) 73 4.3.6 Controlling Damage from Vehicular Traffic 74 4.3.7 Masonry/Concrete dams & Spillways 74 4.3.8 Outlet Works 74 4.3.9 Trash Racks 75 4.3.10 Gates & Hoisting Equipment 75 4.3.11 Electrical System 85 4.3.12 Metal Component Maintenance 86 4.3.13 Access Roads 86 4.3.14 General Cleaning 86

4.4 Materials requirements for maintenance during monsoon period 86 4.5 Establishment Requirements 87 4.6 Preparation of O&M budget 87 4.7 Maintenance Records 89

5 INSRUMENTATION AND MONITORING 90 5.1 General Instrument types 90 5.2 Instrumentation at Malampuzha Dam 90 5.3 Frequency of Monitoring 91 5.4 Data Processing and Evaluation 91 5.5 Visual Observations 92 6 Remedial Measures Taken Earlier 93 7 Updating the Manual 97

Annexure 1- Basic Drawings 98 Annexure 2- Hydrology Review 102 Annexure 3- Inspection Report in Earlier Format 115 Annexure 4- Check list for Inspection 136 Annexure 5- Reservoir Operation Rules 175 Annexure 6- Latest DSRP Report 178 Annexure 7- Glossary 201


vii

LIST OF TABLE

Page

1.1 Assignment of Responsibilities for Malampuzha dam 15

1.2 Roles & Responsibilities of AE and AEE 16

1.3 Roles & Responsibilities of EE and SE 17

1.4 Example Performa for recording Flow Data 20

1.5 Periodical collection of Dam and Reservoir Data 21

1.6 List of people to whom copy of the O&M Manual has been provided

26

1.7 Schedule of duties /Inspection 27

1.8 Hydro-Mechanical Inspections /Checks 29

2.1 water level vs storage 33

2.2 Spillway Discharge Calculation 52

2.3 Rule cuvre elevation and storage 60

2.4 Liaising officers for flood co-ordination of Malampuzha Dam 64

4.1 O&M Budget costs (annual) 93

LIST OF FIGURES

Fig1.1 Vicinity Map 9

Fig1.2 Google map of Malampuzha dam 10

Fig1.3 Malampuzha dam Up stream View 10

Fig1.4 Bharathapuzha river basin 11

Fig1.5 Arial view of Malampuzha Dam and Garden 12

Fig1.6 Malampuzha Garden 12

Fig1.7 Spillway 13

Fig1.8 Spillway gate 13

Fig1.9 Spillway operating motors 14

Fig1.10 Spillway motor operating Switch board 14


viii

Fig2.1 Elevation capacity curve/Area capacity Curve 32

Fig2.2 Rule curve for Malampuzha dam(water level) 61

Fig2.3 Rule curve for Malampuzha dam(storage) 61

Fig4.1 Upstream rip rap 77

Fig4.2 Vertical gate 81

Fig4.3 Gantry Crane 86

LIST OF BASIC DRAWINGS IN ANNEXURE 1

Drg1.1 Non over flow section 103

Drg1.2 Spillway Section 104

Drg1.3 Earthen Dam Sections 105

Drg1.4 Layout Plan of dam 106


1

Chapter 1. GENERAL INFORMATION

1. Introduction

This document represents a detailed Operation and Maintenance (O&M) Manual for

Malampuzha dam, Kerala, providing written descriptions of procedures for ensuring that the dam

operations safely and is kept in a good condition by periodic inspections, repairs, maintenance in

a sustainable manner. Timely maintenance is important for the continued safe functioning and

productive use of the dam andreservoir.

The Manual has been prepared primarily for the dam operation’s staff and their supervisors who

are assigned the responsibility for the physical operations and maintenance of the dam. It

contains, as a minimum, all information and instructions necessary for them to perform their

allotted tasks in a safe manner. In addition to instructions for dam operation staff, the Manual

includes all necessary instructions for other staff directly or indirectly involved in operating and

maintaining thedam.

It is essential that the Manual or a copy of the Manual along with supporting data including the

atlas of all drawings and manufacturer’s technical documents is available at site for ready

reference.

1.1 Purpose, location, description ofdam.

The Malampu project commissioned during 1955 comprises of a dam across Malampuzha river,

a tributary of Bharathapuzha, located 8 km from town in Palakkad district .The Project lies

between Latitude 100 48’ & 100 55’ and Longitude between 760 39’ & 760 42’. It consist of a

straight gravity rubble masonry dam of 1626 m length and two earthen dams, namely, saddle I of

100 m length and saddle II of 392m length of rock type. A masonry gravity type spillway in the

center for passing the flood discharge .Two main canals, their branches and distributaries to

irrigate 22554 Ha. land of Palakkaddistrict.


2

1.1.1 Salient Features of Malampuzhadam

SI No Particulars

GENERAL

1 Name Of Irrigation Project Malampuzha Irrigation project

2 Type of Irrigation project Storage

3 Lat. & Long. Lat between 100 48’ & 10055’, Longbetween 760 39’ & 76042’

4 Category of project Major

5 Name of basin Bharathapuzha

6 Name of sub-basin Bharathapuzha

7 Name of the river Malampuzha

8 Name of the tributary Malampuzha

9 Year of commencement of the project construction 1949

10 Year of completion 1955

11

Name of GrammaPanchayath in which the dam is situated

Malampuzha

12 Nearest Town Olavakkode ,Palakkad

13

District

Palakkad

RESERVOIR

1 Type Of Dam Storage


3

2

Dam

Total Length of Dam(m)

Masonary dam-1626.71m( includes saddle 1-100 m ,saddle 2-392 m) and

Earthen dam-222.20 3

Maximum Height of Dam 33.70 m above deepest foundation or

31.70m above lowest river bed 4

Spillway

Length of spill way(m) 55m

5 No of gates 4 No , Vertical lift type

6

Gate size

Width(m)

10.97m

7 Height (m) 4.57m

8

Reservoir

Full Reservoir level(FRL)(m) 115.06m

9 Maximum water level(m) 115.06m

10 Minimum draw down level(m)

91.44m

11 Deepest Bed level 83.65 m

12 Gross storage capacity at FRL

226 Mm3

13 Dead storage 2.4 Mm3

14 Water spread area 22 Sq. Km

15 Catchment area

147.635 Sq. Km

SI No

Canal Details

Total Length (km)

Area/ Discharge

1

Main Canal

Left bank 31.68 21.24 m3/sec

Right Bank 32 4.05 m3/sec

2 Branch canal 34.2

3 Major Distributory 45.11

4

Cultivable Command Area

21349Ha

August 2020

O&M Manual of Malampuzha

Fig.1.1Vicinity Map

Malampuzha Dam

4


5

Fig.1.2 Google map of Malampuzhadam

Fig1.3 Malampuzha dam Up streamView


6

Fig.1. 4 Bharathapuzha river basin

1.1.2 Brief history ofDam

The Malampuzha Irrigation Project is the first large scale Irrigation system attempted in the Malabar

District of old Madras State. The project works were commenced during 1949 i.e. the First Five Year plan

and completed and commissioned during 1955 under Second Five Year Plan. At the time of formation of

the State of Kerala in November 1956 the dam was fullyoperational.

The aim of Malampuzha Project was not only to bring new lands to cultivation and to supply water for the

first crop, but also to supplement the rainfall in the season between the South West and North East

monsoon in December and January.

Malampuzha Project is a multipurpose project i.e. Irrigation, drinking water supply, Fisheries, Power and

Tourism.


7

Fig.1. 5 Arial view of Malampuzha Dam and Garden

Fig.1. 6 Malampuzha Garden


8

Fig.1. 7 Spillway

Fig.1. 8 Spillway gate


9

Fig.1. 9 Spillway operating motors

Fig.1. 10 Spillway motor operating Switch board


10

1.2 Assignment of responsibleofficials

The Irrigation Department, Government of Kerala is the owner and has the final

authority and responsibility for the operation and maintenance of the dam. Identification of all

areas of responsibilities connected with the operation and maintenance of the dam are covered in

this section. The officer’s responsibilities for the various functions are identified by their

designation and, in particular, the responsibilities of operating personnel are specifically

identified in below and include regularly scheduled duties which staff personnel are required to

perform as outlined in the followingtables:

Table 1.1 – Assignment of Responsibilities for Malampuzha dam

Sl No Particulars Remarks

1.

Implementing Agency

Irrigation Department, Government of Kerala

2. Project Administration Officer in charge

Chief Engineer, Project 1, Kozhikode.Phone No:04952385595. Email – [email protected]

3. Operations of Equipment at theDam

Executive Engineer, Irrigation Division, Malampuzha Phone.0491 2815331. [email protected]

4. Reservoir inflow and Flood forecasting

Executive Engineer, Irrigation Division, Malampuzha Phone.0491 2815331

5. Authorizing spillway flood releases

Executive Engineer, Irrigation Division, Malampuzha Phone.0491 2815331

6.

Authorizing releases for various purposes like irrigation , water supply ,hydro-power, etc.

Executive Engineer, Irrigation Division, Malampuzha. Phone.0491 2815331

7. Recording reservoir Data Executive Engineer, Irrigation Division, Malampuzha. Phone.0491 2815331

8. Routine inspection Executive Engineer, Irrigation Division, Malampuzha. Phone.0491 2815331

9. Maintenance Executive Engineer, Irrigation Division, Malampuzha.. Phone.0491 2815331

10. Instrumentation Executive Engineer, Irrigation Division, Malampuzha. Phone.0491 2815331


11

1.2.1 Roles and Responsibilities of the AE andAEE

Table 1.2 – Roles & Responsibilities of AE and AEE

General responsibilities of AE and AEE

1. Operation of Canal sluices as per the direction of higher officers.

2. Operation of Spillway shutters as per the direction of higher officers.

3.

Daily reporting of Reservoir data as per the direction of higher officers.

4.

Inspecting the gallery and shutter operation on daily basis and reporting any irregularities to higher officers.

During flood conditions

1.

Maintainthereservoirwaterlevelgaugeregisterandtoreportthereservoirdatainevery 6 hrs. when the reservoir reaches 113 m, reporting of reservoir data in every 2 hrs. when it reaches 114 m and reporting of data in every one hour when it reaches 114.46 m and to bring to the notice ofEE/SE/CE.

2.

Giving timely warning, to District administration, District Police Chief, Tehsildar Palakkad and Palakkad, District Administration, Local Self Government Institutions, Media, and all higher officials of the Department, such as first warning when the reservoir reaches 113.00 m “Malampuzha reservoir level at 113 m, only is 2.06 m below F.R.L”.”Shutters are likely to be opened soon”. Second warning when the reservoir reaches 114.00 “Malampuzha reservoir level at 114m ,Shutters are likely to be opened ”. Giving Third and final warning when the water level reaches 114.46 m “Malampuzha reservoir level at 114.46m, shutters being opened”.

3.

When the reservoir level attains 113 m AE should closely watch the inflow rate and levels. He should watch closely the downstream face of the earthen dam, seepages through toe drains and drainage gallery.

4. Assist the EE/SE/CE to issue notification to the villagers downstream in Newspapers, Radio ,TV News channel to be alert regarding the flood situation

5.

Assist the EE/SE/CE to coordinate with the Revenue authorities (District Administration) to alert the downstream villagers to evacuate the flood zone to prevent loss of life and lives tock

6.

Assess the inflows in the reservoir as per the approved reservoir operation and to preparePerformaconsistingofthestatusofthereservoircapacityandreleasesfromthe reservoir as per the standard Performa and to submit to theEE/SE/CE

7.

Submit to the EE/SE/CE on the inflows and releases from the reservoir and status of the reservoir twice in the day.

8. Maintain the spillway crest gate operation log book

9.

Operate the Spillway crest gates for flood mitigation as per the instructions of the EE/SE/CE and to update the Gate operation Log book


12

10.

Maintain the pump operation log books for the dewatering pumps in the drainage gallery and to submit to EE/SE/CE

11. Observe the gates and to see that the drain holes are not clogged and floating debris is not deposited in the gate components

12.

Monitor the condition of the Welding transformers ,gas cuttings ets, umbrellas, tool kits torches chain blocks ropes ballies etc.on daily basis and to see that things are in place to handle any emergency situation

13.

Observe the Gates, hoists and handling equipment during operation for the smooth movements and to immediately report any untoward excessive sounds in the motors ,pumps or vibrations in the gate

14. Observe the dam top, embankment ,cat walk, approach roads are well maintained by housekeeping personnel

15.

Observe the performance of the Dam and its appurtenant structures/Gates and Hoists during flood water releases and to report to the EE/SE/CE in case of any untoward incidents or malfunctioning of the gates of excessive seepages, leakagesetc.

16.

Assist EE/SE/CE to share the flow data and the reservoir storage details to the Media on day to day basis

1.2.2 Roles and Responsibilities of the EE andSE

Table 1.3 – Roles & Responsibilities of EE and SE

Step Flood condition assessment, warning, flood mitigation, and other responsibilities

1.

To issue notification to the villagers down stream in Newspapers ,Radio, TV News channel to be alert regarding the flood situation

2.

Assist the CE to coordinate with the Revenue authorities (District Administration) to alert the down stream villagers to evacuate the flood zone to prevent lossof life and livestock

3.

Assist the CE to coordinate with the CWC flood monitoring authorities on the flood condition

4.

Submit to the CE on the inflows and releases from the reservoir and status of the reservoir twice in the day

5.

OperatetheSpillwaycrestgatesforfloodmitigationaspertheinstructionsoftheCEandto update the Gate operation Logbook

6.

Observe the seepages in the drainage Gallery with respect to the reservoir head and record the seepages in the infiltration gallery and to immediately bring to the notice of the CE incase of excessive seepage, leakage in any specific blocks and porous drains

7.

Observe the Gates, hoists and handling equipment during operation for the smooth movements and to immediately report any untoward excessive sounds in the motors ,pumps or vibrations in the gate

8.

Observethedamtop,embankment,catwalk,approachroadsarewellmaintainedbyhousekeepi ngpersonnel

9.

Observe the performance of the Dam and its appurtenant structures/Gates and Hoists during flood water releases and to report to the CE in case of any untoward incidents or malfunctioning of the gates of excessive seepages ,leakages etc.

10. Assist CE to share the flow data and the reservoir storage details to the Media on day to day basis


13

Table -Dam Safety Organization's Responsibilities

The following are the basic emergency planning and response roles and responsibilities for the dam safety authorities (State and National level). The Dam Safety Organization (DSO) is the first point of contact for BLUE alert.

Is the responsibility of the Dam Safety Organizations undertaking an engineering assessment of the safety hazard at thedam.

The DSO may inspect the Dam at its discretion and inform the Emergency Planning Manager if Malampuzha dam is considered to be at BLUEalert.

The DSO may advise the Dam Owner/Emergency Planning Manager of remedial actions to take if BLUE/ORANGE eventsoccur.

TheDSOmayhaveanactiveroleinORANGE/REDlevelsofalert.TheDSO may advise the Dam Owner/Emergency Planning Manager of the emergency leveldetermination.

A DSO's officer may be called on to be the Subject Matter Expert at the Emergency Operation/ResponseCenter.

The DSO is responsible for reviewing and accepting the Emergency Action Plan, before its finalpublication.

State Dam Safety Organization shall constitute a Dam Safety Review Panel consisting of engineers, geologist and hydrologist to analyze the distress conditions of Damperiodically.

Support for the preparation of asset management plans, emergency preparedness plans, emergency warning systems, flood plain mapping, preparation of flood inundation maps in different areas for the river Basin and downstream impact mitigationmeasures

Focus on legal, regulatory and technical frameworks for dam safetyassurance

Participate/Conduct a stake holders meeting before finalization of the Emergency ActionPlan

1.3 Collection & Reporting of Dam and ReservoirData

A proforma is provided to ensure that dates and times for the collection and reporting of vital information is recorded and documented for the record.


14

Reservoir water surfaceelevation. Reservoirinflow.

Spillwayoutflow.

Riverreleases.

Irrigation, water supply and hydropowerreleases.

Weather relateddata

Instrumentationdata

Water quality

Instructions and a standard Performa for collection and reporting of inflow and outflow data, and other pertinent data, is shown in Figure 5 below.

Records of the following operations at Malampuzha dam are to be maintained in a chronological manner for reference. These records are helpful for identifying preventative maintenance measures that may need to be taken up, trouble shooting the cause of potential equipment failure and documenting development of any unusual conditions.

Date andTime Attendancestatementduringnormaloperations–bothduringmonsoonandnon-

monsoonperiods. Operations of the spillway gates and outletworks. Operating hours of mechanicalequipment. Testing/Operation of spillway gates and associatedcontrols. Testing/operation of Outlet gates, valves and associatedcontrols, Maintenance activities carriedout. Reservoir and daminspections. Unusual conditions or occurrences, including acts ofvandalism. Attendance statement at the dam during emergencyoperations. Changes to normal operatingprocedures.

Communication networkchecks.

Safety and specialinstructions. Names of officers and staff carrying out inspections andmaintenance. Any other item pertaining to the operation and maintenance of thedam.


15

Table1. 4– Example Proforma for recording Flow Data

FortheMonthof

Date

Time

Water level

in Mtr.

Inflow in Cumecs

Outflow in Cumecs

Reservoir Capacity in Mm3

Spillway Gates

Sluice Release

Total O/F


16

Following records are kept in the office of the Assistant Engineer at Project site

1. Attendancestatement

2. Operation of spillway gates and outletworks.

3. Operation hours of mechanicalequipments.

4. Testing/operation of spillway gates, stop logs and associatedcontrols.

5. Testing / operation of outlet gates valves and associatedcontrols.

6. Maintenanceregister

7. Inspection of dam andreservoir

8. Unusual conditions of occurrences includingvandalism

9. Attendance statement at the dam during emergencyoperation

10. Changes to normal operatingprocedures.

11. Communication networkchecks

12. Safety and specialinstructions

Periodical collection of Dam and Reservoir Data are done as follows:

Table 1.5: Periodical collection of Dam and Reservoir Data

Reservoir water surface elevation This is collected daily Reservoir inflow This is calculated daily Spillway outflow This is calculated during spill River releases Drought season water releases to river when required Irrigation, water supply and hydropower releases

Mainly used for Irrigation and water supply. Daily measurements is calculated when water releases.

Weather related data Collected and reported daily Surveillance/Security arrangements Provided at one security check posts near dam, The watch and

ward of the dam structure and premises is arranged by SEVAK an agency under the Chairmanship of District Collector. CCTV surveillance will be provided soon to cover thedam area and adjoining premises.

Water quality Water sample analysis is also conducting once in a month. The analysis consists of Physical & Chemical tests are being


17

conducted by KWA Laboratory Malampuzha Attendance statement during normal operations

Both during monsoon and non-monsoon period maintained at field office.

Operations of the spillway gates and outlet works

The spill way is designed for a safe discharge of 850 m3/s . There are 4 no of vertical gates for spillway operation. Take record of actual operations

Operating hours of mechanical equipment

Maintained at field office

Testing /operation of spillway gates and associated controls

The testing and operation are being carried out as per the manual and maintenance schedule. Other details maintained at field office

Testing operation of outlet valves and associated controls

Maintained at field office

Maintenance activities carried out Details maintained at field office Reservoir and dam inspections Periodically inspected and details maintained at field office Unusual conditions or occurrences including acts of vandalism

Details maintained at field office

Attendance statement at dam during Emergency operations


Changes to normal operating procedure


Communication network checks Network is available at Dam site at certain locations, Safety and special instructions Safety equipment are available Names and addresses ofofficial visitors

Record of inspections maintained at office

1.4 Public Utilities andSafety

As safety of Staff is of prime concern, Safety instructions & protection measures at the dam are carried out by all staff.

Signboards are displayed in the area for access to various public conveniences.

Similarly, sign boards are also displayed for easy access to the following public utilities.

Medicaldispensary-Malampuzha Police station-Malampuzha-04912815284 Safetyequipment

1.5 RestrictedAreas

Display boards at site indicate restricted areas, where general public is not allowed to enter. While the dam top road is allowed for public access, the following are restricted areas at Malampuzhadam.

Upstream and downstream slopes of thedam/dyke.

Spillway crest gates, control chambers, stilling basin, and exitchannel.


18

Operation and drainagegalleries.

Intake tower, control rooms, power house, and tail racechannel.

1.5.1 Details of the Security arrangements at Malampuzha damSite.

The security arrangements of Malampuzha dam are entrusted to

Watchmen (Departmental staffs) are engaged during daytime

For Night hours, SEWAK, an outside agency under the chairmanship of district collector has been entrusted for the security of thedam.

See Layout Plan -Drg1.4 page107

1.6 Staff position, Communication& Warningsystem

Names and designations of the officers and staff posted at Malampuzha dam at different locations, during monsoon &non-monsoon periods, are indicated on the display boards at control rooms and siteoffices.

Communications among the dam operator and the officials usually takes place by telephone..Landline telephones mobile phone is available in the dam site offices could also be used by the dam operators in an emergency

A hierarchy of organizational structure for the control and safety of Pamba dam is outlined below inFig


19

Overseer Grade 3, Dam Section, Malampuzha

Assistant Engineer, Dam Section, Malampuzha

Assistant Executive Engineer, Headworks Sub Division,

Malampuzha

Executive Engineer, Irrigation Division,

Malampuzha

Superintending Engineer, Siruvani Project Circle,

Palakkad

Chief Engineer –Project 1 Kozhikode

Chief Engineer-IDRB, Thiruvananthapuram

Civil Engineering


20

Overseer Grade 1 Malampuzha

Assistant Works Manager(AE) Malampuzha

Works Manager(AEE) Mechanical Sub Division

Malampuzha

Executive Engineer Mechanical Division

Malampuzha

Superintending Engineer Mechanical Ernakulam

Chief Engineer Mechanical Thiruvananthapuram

Mechanical Engineering


21

1.7 Distribution of Operation &MaintenanceManuals

Table1.6 List of people to whom copy of the O&M Manual has been provided

Authority Name, Title, Phone Address No Acceptance Signature

Water Resources Secretary

Secretary to Govt, Water Resources Department,

Secretary to Govt, Water Resources Department, Thiruvanathapuram

2

Chief Engineer, (I&A), Chief Engineer, (I&A), Thiruvanathapuram

2

Chief Engineer ,IDRB Chief Engineer ,IDRB, Thiruvanathapuram

2

Dam Owner(s) and Representatives

Chief Engineer Project - 1 MobileNo:944733265 Office No:04952385595

Office of the Chief Engineer, Projects – I , Kozhikode Email – [email protected]

1

SuperintendingEngineer Office No:04912577425

Siruvani ProjectCircle Palakkad

1

Email- [email protected]

District Collector,Palakkad

District Collector Mobile No:8547610100 Office No:0491-2505266

Office of the DistrictCollector CivilStation Kenathuparambu,Kunathurmedu, Palakkad,Kerala 678013 [email protected]

2

State Dam Safety Organisation

Title : Chief Engineer, IDRB Mobile No: 9961991314 Office No: 0471-2303972 [email protected]

Office of the Chief Engineer (I&D), IDRB, VikasBhavan Thiruvananthapuram

1

Central Dam Safety Organisation

Chief Engineer, CDSO Mobile No: 9717333808 Office No: 011-26106848

SewaBhavan, Sector 1, RK Puram, NewDelhi, Delhi110066

CWC Library Buildings, RKPuram, NewDelhi, Delhi110066

2

Director, DRIP Mobile No: 9958975928 Office No: 011-26192633

State Emergency Operation Center, Kerala Disaster Management Authority

Member Secretary Email : [email protected] Mobile No:9400202927 Office No:0471-2331345

Observatory HillsMuseum,VikasBhavan P O Thiruvananthapuram, Kerala 695033

1

National Disaster Management Authority

Brig. Ajay Gangwar Advisor [email protected]

NDMA Bhawan,A-1, Safdarjung Enclave,

1

Mobile No: New Delhi - 110029 Office No:011-26701886

E-mail: [email protected]

District Police District Police Chief, Office of the District Police Chief, 1 Chief Palakkad

Mobile No: 9497996977 PalakkadPudupalliTheruvu, Nurani, Palakkad

Office No: 0491-2534011 Email: [email protected]

1.8 Supporting Documents &ReferenceManual


22

Emergency Action Plan (EAP).

Irrigation operating instructions.

Administrative procedures.

Dam site security plan

Manufacturer’s instructions & drawings.

Guideline for Safety Inspection of dams

Reservoir Management Plan (land, recreation, fish and wildlife).

Regional Communications Directory for dams

Instrumentation reports and/or results.

1.9 Typical schedule of Duties

Schedules of duties being performed by the staff assigned to various occasions and components of Malampuzha dam are provided in this section. General schedule of duties/inspections to be carried out for the operation and maintenance of the dam by the concerned official are tabulated below.

Table 1.7: Schedule of duties /Inspection

Sl. No

Component/Duty Frequency Personnel

1 Visual inspection of dam including Crest of dam (Dam top), Upstream and downstream faces, visible portions of foundation and abutments, Galleries, Spillway and its energy dissipation arrangements, sluices etc.

Daily Sub Engineer/Dam operators on contract

2 Record water surface elevation, reservoir inflow and spillway discharge.

Daily (Hourly basis during monsoon)

Sub Engineer/Dam operators on contract

3 Record meteorological data, Record releases from canal sluices

Daily Sub Engineer/Dam operators on contract

4 Check security and safety devices, Complete logbook / site register which include the above information.

Daily Assistant Engineer

5 Record seepage from drainage systems, Gallery drains etc. and record meteorological data. Weekly

Weekly Sub Engineer/Dam operators on contract

6 Visual inspection of dam including Crest of dam (Dam top), Upstream and downstream faces, visible portions of foundation and abutments, Galleries, Spillway and its energy dissipation arrangements, canal sluices etc.

Weekly Assistant Engineer

7 Weekly Assistant Engineer 7 Check stand by generator (DG Sets), Drainage systems, Gallery drains etc.

Weekly Assistant Engineer


23


Fort nightly Assistant Executive Engineer

9 Fort nightly Assistant Executive Engineer Fort nightly Assistant Executive 9 Check security and safety devices, logbook

and site register which include the above information

Engineer

10 Check standby generator (DG Sets), Drainage systems, Toe drains & Gallery drains


11 Measuring devices, communication devices, status of instruments, vegetation growth


12 Check Sign/Warning display boards near vulnerable locations



Monthly Executive Engineer

14 Monthly Executive Engineer 14 Check measuring devices/Instruments, Security and safety devices, Communication Devices, Status of Vegetation growth, – rectification, if needed


15 Check Sign/Warning display boards near vulnerable locations


16 Replace fuse light bulbs, Inspect to maintain ventilation system, cleaning of control panel boards.

Monthly Assistant Engineer

17 Check outlet works, updating operating instruction, check gate air vents, clean gate control switchboxes, check operation of gates, grease gate hanger/dogging

Quarterly Executive Engineer

18 Check condition of canal sluice works & its d/s structure, Check operation of Emergency gate & regulation gates for canal sluices


19 Check condition of spillway structure, Check for debris in inlet channel, Check operation of spillway gates, Check for damages in spillway glacis, energy dissipation arrangement, d/s area etc, Check and clear spillway bridge drains, check various operations being conducted from Control room etc..


20 Check for adherence to instrumentation schedule, Record pertinent information in Operation of Gates, Check condition of V- notch/seepage measuring devices, Check hydro mechanical components.



24

21 Inspection of Spillway & outlet works, hydro mechanical components, Check paint on gates, Check lubrication of wire ropes etc. and application of cardamom compound, Check mechanical hoist bearings and flexible coupling bearings, Check gear systems, Exercise gates, Check lubrication of gate rollers, Check rubber seals and sealclamp bar.

(Pre and Post Monsoon)

Superintending Engineer along with

Executive Engineer in charge of dam

22 Submission of Inspection report to State DSO, CWC and uploading into DHARMA.

Half yearly Chief Engineer/ Superintending

Engineer 23 Comprehensive inspections Annually Dam Safety Authority

along with Dam Owners

24 Inspect dam and gate structures, energy dissipation arrangement, which normally are underwater (by dewatering or by divers). Review Dam operation procedures and EAP and update as necessary.

Five Yearly Chief Engineer/ Superintending

Engineer

25 Comprehensive inspection of performance of the dam and gate structures and reservoirs, energy dissipation arrangement and allied structures including dam operating systems

Ten Yearly DSRP

Table-1.8 Hydro-Mechanical Inspections /Checks

Sl. No. Embedded Part Frequency

1

Checking of seal beams Seal Seats ,Guide track & all other exposed embeddedpartswithrespecttotheiralignment,distortionifanydue to continuous use, pitting and unnecessary cracks due towear &carrying out requisite repairs,rectification by welding, grindingetc.

Half Yearly

2 Removingdebris&otherforeignmaterialdepositedonembeddedparts &cleaning the same Monthly

3 Al l cracks &defective weld joints to be as curtained & rectified. Half Yearly

4

All dirt, debris, grit ,foreign material etc.to be removed from trunnion assemblies as well as trunnion chair and lubricate trunnion bearing &the slidingsurface ontrunnionchairwithspecifiedlubricant/gradetoensuresmoothslidingm

Monthly

5

All nut bolts connecting Trunnion Assembly &Trunnion Chair and Trunnion &Yoke, girder Trunnion pin lock plate to be checked&Tightenedandreplacementthesameiffounddefective.

Monthly

a. GateStructure

Sl. No. Embedded Part Frequency


25

1

Regularinspectionofthegatealongwiththehoisttobecarriedoutdailyto ensurethatthereisnounusualdevelopment/observation

Daily

2 Check all welding for soundness &rectify defects Quarterly

3

Check welding between arms& horizontal girders as well as arms &Trunnion with the help of magnifying glass for cracks/defects and rectify the defects.

Quarterly

4 Clean all drain boles including those in end arms, horizontal girders & Trunnion

Quarterly

5 Checkallnuts&boltsprovidedandtightenthem,andreplacethede- fectivenuts&bolts

Quarterly

6 Checkup stream face of Skin plate for pitting, scaling and corrosion .Scaling formation are to be removed. Pitting shall be filled with weld& ground .Corroded surface shall be cleaned & painted

Yearly

7

Joints of side & bottom rubber seals to be checked for the inproper alignment and fixing &to be rectified/adjusted if there is leakage through joints

Monthly

8

Nuts &bolts for rubber seal connection to be tightened and damaged nuts and bolts to be replaced

Quarterly

9

The excessive widespread leakages if any shall be reported to the engineer in charge .If the seals are required tobereplacedthesameshall- becarriedoutaftersupplyofrubbersealbythedepartmentfreeof cost in case the change of rubber seals is more than once during to the maintenance period of five years

Quarterly

10 The guide roller pin is o be lubricated Quarterly

11 The maintenance of the equipment cleaning &shall include inspection, checking and ascertaining the deficiencies in the equipment for its smooth& trouble free operation .The deficiencies noticed shall berectified by resorting to cleaning, adjustment ,repairs ,replacement of troubled/damaged parts as per therequirement

As per requirement

12 Necessary maintenance records are to be prepared as a result of periodical inspection and submitted for deciding actions in respect of necessary repair/replacement of parts

Monthly


26

Chapter 2. PROJECT OPERATION

The operation of a Project involves regulation of its reservoir as per project specific requirements, keeping records and ensuring public safety and normal or day to day operation of component dams maintaining structural safety.

2.1 Basicdata

2.1.1 Area capacitycurve

Area Capacity Table

Elevation

(m)

Storage

(Mm3)

Area

(Sq Km)

115.06 225.9999 22.78

113 176.1674 20.12

111 137.882 17.65

109 104.3081 15.63

107 76.2756 13.02

105 53.1861 10.42

103 34.8379 8.79

101 20.857 6.08

99 10.8765 3.99

97 4.6544 2.54

95.5 2.388 1.33

95 1.6124 1.27

93 0.3642 0.58


27

Fig 2.1 Elevation capacity curve/Area capacity Curve


28

Table 2.1water level vs storage WATER LEVEL STORAGE WATER LEVEL STORAGE

in Feet

in Metre

in Mcft

in MM³ in

Feet in

Metre in

Mcft in MM³

305.05 92.98 12.42 0.3517 307.15 93.62 26.15 0.7405 305.10 92.99 12.64 0.3579 307.20 93.63 26.59 0.7529 305.15 93.01 12.86 0.3642 307.25 93.65 26.81 0.7592 305.20 93.02 13.08 0.3704 307.30 93.67 27.25 0.7716 305.25 93.04 13.52 0.3828 307.35 93.68 27.70 0.7844 305.30 93.06 13.74 0.3891 307.40 93.70 27.92 0.7906 305.35 93.07 14.18 0.4015 307.45 93.71 28.36 0.8031 305.40 93.09 14.41 0.4080 307.50 93.73 28.58 0.8093 305.45 93.10 14.85 0.4205 307.55 93.74 29.03 0.8220 305.50 93.12 15.07 0.4267 307.60 93.76 29.25 0.8283 305.55 93.13 15.51 0.4392 307.65 93.77 29.69 0.8407 305.60 93.15 15.73 0.4454 307.70 93.79 29.91 0.8470 305.65 93.16 16.18 0.4582 307.75 93.80 30.36 0.8597 305.70 93.18 16.40 0.4644 307.80 93.82 30.58 0.8659 305.75 93.19 16.84 0.4769 307.85 93.83 31.02 0.8784 305.80 93.21 17.06 0.4831 307.90 93.85 31.24 0.8846 305.85 93.22 17.51 0.4958 307.95 93.86 31.68 0.8971 305.90 93.24 17.73 0.5021 308.00 93.88 31.91 0.9036 305.95 93.25 18.17 0.5145 308.05 93.89 32.35 0.9160 306.00 93.27 18.39 0.5207 308.10 93.91 32.57 0.9223 306.05 93.28 18.84 0.5335 308.15 93.92 33.01 0.9347 306.10 93.30 19.06 0.5397 308.20 93.94 33.24 0.9413 306.15 93.31 19.50 0.5522 308.25 93.95 33.68 0.9537 306.20 93.33 19.72 0.5584 308.30 93.97 33.90 0.9599 306.25 93.35 20.17 0.5712 308.35 93.99 34.34 0.9724 306.30 93.36 20.61 0.5836 308.40 94.00 34.79 0.9851 306.35 93.38 20.83 0.5898 308.45 94.02 35.01 0.9914 306.40 93.39 21.27 0.6023 308.50 94.03 35.45 1.0038 306.45 93.41 21.49 0.6085 308.55 94.05 35.67 1.0101 306.50 93.42 21.94 0.6213 308.60 94.06 36.11 1.0225 306.55 93.44 22.16 0.6275 308.65 94.08 36.34 1.0290 306.60 93.45 22.60 0.6400 308.70 94.09 36.78 1.0415 306.65 93.47 22.82 0.6462 308.75 94.11 37.00 1.0477 306.70 93.48 23.27 0.6589 308.80 94.12 37.44 1.0602 306.75 93.50 23.49 0.6652 308.85 94.14 37.67 1.0667 306.80 93.51 23.93 0.6776 308.90 94.15 38.11 1.0792 306.85 93.53 24.15 0.6839 308.95 94.17 38.33 1.0854 306.90 93.54 24.60 0.6966 309.00 94.18 38.77 1.0978 306.95 93.56 24.82 0.7028 309.05 94.20 38.99 1.1041 307.00 93.57 25.26 0.7153 309.10 94.21 39.44 1.1168 307.05 93.59 25.48 0.7215 309.15 94.23 39.66 1.1230 307.10 93.60 25.93 0.7343 309.20 94.24 40.10 1.1355


29

WATER LEVEL STORAGE WATER LEVEL STORAGE in

Feet in

Metre in

Mcft in MM³ in

Feet in

Metre in

Mcft in MM³

309.25 94.26 40.32 1.1417 309.75 94.41 43.87 1.2423 309.30 94.27 40.77 1.1545 309.80 94.43 44.09 1.2485 309.35 94.29 40.99 1.1607 309.85 94.44 44.53 1.2609 309.40 94.31 41.43 1.1732 309.90 94.46 44.76 1.2675 309.45 94.32 41.87 1.1856 309.95 94.47 45.20 1.2799 309.50 94.34 42.32 1.1984 310.00 94.49 45.42 1.2861 309.55 94.35 42.54 1.2046 310.05 94.50 45.86 1.2986 309.60 94.37 42.76 1.2108 310.10 94.52 46.08 1.3048 309.65 94.38 43.20 1.2233 310.15 94.53 46.53 1.3176 309.70 94.40 43.43 1.2298 310.20 94.55 46.97 1.3300 309.75 94.41 43.87 1.2423 310.25 94.56 47.41 1.3425 309.80 94.43 44.09 1.2485 310.30 94.58 47.63 1.3487 309.85 94.44 44.53 1.2609 310.35 94.59 48.08 1.3615 309.90 94.46 44.76 1.2675 310.40 94.61 48.30 1.3677 309.95 94.47 45.20 1.2799 310.45 94.63 48.74 1.3802 310.00 94.49 45.42 1.2861 310.50 94.64 48.96 1.3864 310.05 94.50 45.86 1.2986 310.55 94.66 49.41 1.3991 310.10 94.52 46.08 1.3048 310.60 94.67 49.63 1.4054 310.15 94.53 46.53 1.3176 310.65 94.69 50.07 1.4178 310.20 94.55 46.97 1.3300 310.70 94.70 50.29 1.4241 310.25 94.56 47.41 1.3425 310.75 94.72 50.74 1.4368 310.30 94.58 47.63 1.3487 310.80 94.73 50.96 1.4430 310.35 94.59 48.08 1.3615 310.85 94.75 51.40 1.4555 310.40 94.61 48.30 1.3677 310.90 94.76 51.62 1.4617 310.45 94.63 48.74 1.3802 310.95 94.78 52.06 1.4742 310.50 94.64 48.96 1.3864 311.00 94.79 52.29 1.4807 310.55 94.66 49.41 1.3991 311.05 94.81 52.73 1.4931 310.60 94.67 49.63 1.4054 311.10 94.82 52.95 1.4994 310.65 94.69 50.07 1.4178 311.15 94.84 53.39 1.5118 310.70 94.70 50.29 1.4241 311.20 94.85 53.61 1.5181 310.75 94.72 50.74 1.4368 311.25 94.87 54.06 1.5308 310.80 94.73 50.96 1.4430 311.30 94.88 54.28 1.5370 310.85 94.75 51.40 1.4555 311.35 94.90 54.72 1.5495 310.90 94.76 51.62 1.4617 311.40 94.91 54.94 1.5557 309.35 94.29 40.99 1.1607 311.45 94.93 55.39 1.5685 309.40 94.31 41.43 1.1732 311.50 94.95 55.83 1.5809 309.45 94.32 41.87 1.1856 311.55 94.96 56.05 1.5872 309.50 94.34 42.32 1.1984 311.60 94.98 56.49 1.5996 309.55 94.35 42.54 1.2046 311.65 94.99 56.72 1.6061 309.60 94.37 42.76 1.2108 311.70 95.01 56.94 1.6124 309.65 94.38 43.20 1.2233 311.75 95.02 58.01 1.6427 309.70 94.40 43.43 1.2298 311.80 95.04 58.55 1.6579


30

WATER LEVEL STORAGE WATER LEVEL STORAGE

in Feet

in Metre

in Mcft

in MM³ in

Feet in

Metre in

Mcft in MM³

311.85 95.05 59.62 1.6882 313.90 95.68 93.47 2.6468 311.90 95.07 60.16 1.7035 313.95 95.69 94.00 2.6618 311.95 95.08 61.23 1.7338 314.00 95.71 95.08 2.6924 312.00 95.10 61.77 1.7491 314.05 95.72 95.61 2.7074 312.05 95.11 62.84 1.7794 314.10 95.74 96.69 2.7380 312.10 95.13 63.92 1.8100 314.15 95.75 97.23 2.7532 312.15 95.14 64.46 1.8253 314.20 95.77 98.30 2.7835 312.20 95.16 65.53 1.8556 314.25 95.78 98.84 2.7988 312.25 95.17 66.07 1.8709 314.30 95.80 99.91 2.8291 312.30 95.19 67.14 1.9012 314.35 95.81 100.45 2.8444 312.35 95.20 67.68 1.9165 314.40 95.83 101.52 2.8747 312.40 95.22 68.76 1.9471 314.45 95.84 102.06 2.8900 312.45 95.23 69.29 1.9621 314.50 95.86 103.13 2.9203 312.50 95.25 70.37 1.9927 314.55 95.87 103.67 2.9356 312.55 95.27 70.90 2.0077 314.60 95.89 104.75 2.9662 312.60 95.28 71.98 2.0382 314.65 95.91 105.28 2.9812 312.65 95.30 72.51 2.0533 314.70 95.92 106.36 3.0118 312.70 95.31 73.59 2.0838 314.75 95.94 106.89 3.0268 312.75 95.33 74.66 2.1141 314.80 95.95 107.97 3.0574 312.80 95.34 75.20 2.1294 314.85 95.97 108.51 3.0727 312.85 95.36 76.27 2.1597 314.90 95.98 109.58 3.1030 312.90 95.37 76.81 2.1750 314.95 96.00 110.12 3.1182 312.95 95.39 77.89 2.2056 315.00 96.01 111.19 3.1485 313.00 95.40 78.43 2.2209 315.05 96.03 111.73 3.1638 313.05 95.42 79.50 2.2512 315.10 96.04 112.80 3.1941 313.10 95.43 80.04 2.2665 315.15 96.06 113.34 3.2094 313.15 95.45 81.11 2.2968 315.20 96.07 114.41 3.2397 313.20 95.46 81.65 2.3121 315.25 96.09 114.95 3.2550 313.25 95.48 82.72 2.3424 315.30 96.10 116.03 3.2856 313.30 95.49 83.26 2.3577 315.35 96.12 116.56 3.3006 313.35 95.51 84.33 2.3880 315.40 96.13 117.64 3.3312 313.40 95.52 84.87 2.4032 315.45 96.15 118.17 3.3462 313.45 95.54 85.94 2.4335 315.50 96.16 119.25 3.3768 313.50 95.55 86.48 2.4488 315.55 96.18 120.32 3.4071 313.55 95.57 87.55 2.4791 315.60 96.19 120.86 3.4224 313.60 95.59 88.09 2.4944 315.65 96.21 121.93 3.4527 313.65 95.60 89.17 2.5250 315.70 96.23 122.47 3.4680 313.70 95.62 89.71 2.5403 315.75 96.24 123.54 3.4983 313.75 95.63 90.78 2.5706 315.80 96.26 124.08 3.5136 313.80 95.65 91.32 2.5859 315.85 96.27 125.16 3.5441 313.85 95.66 92.39 2.6162 315.90 96.29 125.69 3.5591


31


in Feet

in Metre

in Mcft

in MM³ in

Feet in

Metre in

Mcft in MM³

315.95 96.30 126.77 3.5897 318.10 96.96 161.68 4.5783 316.00 96.32 127.30 3.6047 318.15 96.97 162.76 4.6088 316.05 96.33 128.38 3.6353 318.20 96.99 163.30 4.6241 316.10 96.35 128.91 3.6503 318.25 97.00 164.37 4.6544 316.15 96.36 129.99 3.6809 318.30 97.02 165.48 4.6859 316.20 96.38 130.53 3.6962 318.35 97.03 167.69 4.7484 316.25 96.39 131.60 3.7265 318.40 97.05 168.79 4.7796 316.30 96.41 132.14 3.7418 318.45 97.06 171.00 4.8422 316.35 96.42 133.21 3.7721 318.50 97.08 172.11 4.8736 316.40 96.44 133.75 3.7874 318.55 97.09 174.32 4.9362 316.45 96.45 134.82 3.8177 318.60 97.11 175.42 4.9673 316.50 96.47 135.36 3.8330 318.65 97.12 177.64 5.0302 316.55 96.48 136.44 3.8635 318.70 97.14 178.74 5.0613 316.60 96.50 136.97 3.8786 318.75 97.16 180.95 5.1239 316.65 96.51 138.05 3.9091 318.80 97.17 183.16 5.1865 316.70 96.53 139.12 3.9394 318.85 97.19 184.27 5.2179 316.75 96.55 139.66 3.9547 318.90 97.20 186.48 5.2805 316.80 96.56 140.73 3.9850 318.95 97.22 187.58 5.3117 316.85 96.58 141.27 4.0003 319.00 97.23 189.79 5.3742 316.90 96.59 142.35 4.0309 319.05 97.25 190.90 5.4057 316.95 96.61 142.88 4.0459 319.10 97.26 193.11 5.4683 317.00 96.62 143.96 4.0765 319.15 97.28 194.22 5.4997 317.05 96.64 144.50 4.0918 319.20 97.29 196.43 5.5623 317.10 96.65 145.57 4.1221 319.25 97.31 197.53 5.5934 317.15 96.67 146.11 4.1374 319.30 97.32 199.52 5.6498 317.20 96.68 147.18 4.1677 319.35 97.34 200.51 5.6778 317.25 96.70 147.72 4.1830 319.40 97.35 202.50 5.7342 317.30 96.71 148.79 4.2133 319.45 97.37 203.49 5.7622 317.35 96.73 149.33 4.2286 319.50 97.38 205.48 5.8185 317.40 96.74 150.40 4.2588 319.55 97.40 206.47 5.8466 317.45 96.76 150.94 4.2741 319.60 97.41 207.58 5.8780 317.50 96.77 152.02 4.3047 319.65 97.43 207.69 5.8811 317.55 96.79 152.55 4.3197 319.70 97.44 207.91 5.8874 317.60 96.80 153.63 4.3503 319.75 97.46 208.03 5.8907 317.65 96.82 154.16 4.3653 319.80 97.48 208.25 5.8970 317.70 96.83 155.24 4.3959 319.85 97.49 208.47 5.9032 317.75 96.85 156.31 4.4262 319.90 97.51 208.59 5.9066 317.80 96.87 156.85 4.4415 319.95 97.52 210.13 5.9502 317.85 96.88 157.92 4.4718 320.00 97.54 210.90 5.9720 317.90 96.90 158.46 4.4871 320.05 97.55 212.44 6.0156 317.95 96.91 159.54 4.5177 320.10 97.57 213.21 6.0374 318.00 96.93 160.07 4.5327 320.15 97.58 214.75 6.0810 318.05 96.94 161.15 4.5633 320.20 97.60 215.52 6.1028


32


in Feet

in Metre

in Mcft

in MM³ in

Feet in

Metre in

Mcft in MM³

320.25 97.61 217.18 6.1498 322.15 98.19 276.77 7.8372 320.30 97.63 218.06 6.1748 322.20 98.21 278.09 7.8746 320.35 97.64 219.83 6.2249 322.25 98.22 280.75 7.9499 320.40 97.66 220.71 6.2498 322.30 98.24 282.07 7.9873 320.45 97.67 222.48 6.2999 322.35 98.25 284.72 8.0624 320.50 97.69 223.36 6.3248 322.40 98.27 286.04 8.0997 320.50 97.69 223.36 6.3248 322.45 98.28 288.69 8.1748 320.55 97.70 225.13 6.3750 322.50 98.30 290.02 8.2124 320.60 97.72 226.01 6.3999 322.55 98.31 292.67 8.2875 320.65 97.73 227.77 6.4497 322.60 98.33 293.99 8.3249 320.70 97.75 228.66 6.4749 322.65 98.34 296.64 8.3999 320.75 97.76 230.42 6.5248 322.70 98.36 297.96 8.4373 320.80 97.78 231.31 6.5500 322.75 98.37 300.61 8.5123 320.85 97.80 233.07 6.5998 322.80 98.39 301.94 8.5500 320.90 97.81 234.84 6.6499 322.85 98.40 304.58 8.6247 320.95 97.83 235.72 6.6748 322.90 98.42 305.91 8.6624 321.00 97.84 237.49 6.7250 322.95 98.44 308.56 8.7374 321.05 97.86 238.37 6.7499 323.00 98.45 311.21 8.8125 321.10 97.87 240.13 6.7997 323.05 98.47 312.53 8.8499 321.15 97.89 241.02 6.8249 323.10 98.48 315.18 8.9249 321.20 97.90 242.78 6.8748 323.15 98.50 316.50 8.9623 321.25 97.92 243.67 6.9000 323.20 98.51 319.18 9.0382 321.30 97.93 245.43 6.9498 323.25 98.53 320.53 9.0764 321.35 97.95 245.15 6.9419 323.30 98.54 323.23 9.1528 321.40 97.96 248.08 7.0248 323.35 98.56 324.59 9.1914 321.45 97.98 248.96 7.0498 323.40 98.57 327.29 9.2678 321.50 97.99 250.73 7.0999 323.45 98.59 328.64 9.3060 321.55 98.01 251.61 7.1248 323.50 98.60 331.35 9.3828 321.60 98.02 254.26 7.1998 323.55 98.62 332.70 9.4210 321.65 98.04 255.59 7.2375 323.60 98.63 335.41 9.4977 321.70 98.05 258.23 7.3123 323.65 98.65 336.76 9.5360 321.75 98.07 259.56 7.3499 323.70 98.66 339.46 9.6124 321.80 98.08 262.21 7.4250 323.75 98.68 340.82 9.6509 321.85 98.10 263.53 7.4623 323.80 98.69 343.52 9.7274 321.90 98.12 266.18 7.5374 323.85 98.71 344.88 9.7659 321.95 98.13 267.50 7.5747 323.90 98.72 347.58 9.8424 322.00 98.15 270.15 7.6498 323.95 98.74 348.93 9.8806 322.05 98.16 272.80 7.7248 324.00 98.76 351.64 9.9573 322.10 98.18 274.13 7.7625 324.05 98.77 352.99 9.9956


33


Feet in

Metre in

Mcft in MM³

in Feet

in Metre

in Mcft

in MM³

324.10 98.79 355.69 10.0720 326.05 99.38 448.96 12.7131 324.15 98.80 358.40 10.1487 326.10 99.40 450.63 12.7604 324.20 98.82 359.75 10.1870 326.15 99.41 453.98 12.8553 324.25 98.83 362.46 10.2637 326.20 99.43 457.33 12.9501 324.30 98.85 363.81 10.3019 326.25 99.44 458.99 12.9971 324.35 98.86 366.51 10.3784 326.30 99.46 460.66 13.0444 324.40 98.88 367.87 10.4169 326.35 99.47 464.01 13.1393 324.45 98.89 370.57 10.4934 326.40 99.49 465.68 13.1866 324.50 98.91 371.92 10.5316 326.45 99.50 469.02 13.2812 324.55 98.92 374.63 10.6083 326.50 99.52 472.16 13.3701 324.60 98.94 375.98 10.6466 326.55 99.53 473.72 13.4142 324.65 98.95 378.69 10.7233 326.60 99.55 476.86 13.5032 324.70 98.97 380.04 10.7615 326.65 99.56 478.43 13.5476 324.75 98.98 382.74 10.8380 326.70 99.58 481.56 13.6362 324.80 99.00 384.10 10.8765 326.75 99.59 483.13 13.6807 324.85 99.01 387.12 10.9620 326.80 99.61 486.26 13.7693 324.90 99.03 388.79 11.0093 326.85 99.62 487.83 13.8138 324.95 99.04 392.13 11.1039 326.90 99.64 490.96 13.9024 325.00 99.06 393.81 11.1514 326.95 99.65 492.53 13.9469 325.05 99.08 397.15 11.2460 327.00 99.67 495.66 14.0355 325.10 99.09 398.82 11.2933 327.05 99.68 497.23 14.0800 325.15 99.11 402.16 11.3879 327.10 99.70 500.37 14.1689 325.20 99.12 405.50 11.4825 327.15 99.72 503.49 14.2572 325.25 99.14 407.18 11.5300 327.20 99.73 505.07 14.3020 325.30 99.15 410.52 11.6246 327.25 99.75 508.20 14.3906 325.35 99.17 412.19 11.6719 327.30 99.76 509.77 14.4351 325.40 99.18 415.53 11.7665 327.35 99.78 512.90 14.5237 325.45 99.20 417.20 11.8138 327.40 99.79 514.47 14.5682 325.50 99.21 420.55 11.9086 327.45 99.81 517.60 14.6568 325.55 99.23 423.89 12.0032 327.50 99.82 519.17 14.7012 325.60 99.24 425.56 12.0505 327.55 99.84 522.30 14.7899 325.65 99.26 428.91 12.1454 327.60 99.85 523.87 14.8343 325.70 99.27 430.58 12.1927 327.65 99.87 527.01 14.9232 325.75 99.29 433.92 12.2872 327.70 99.88 528.57 14.9674 325.80 99.30 435.59 12.3345 327.75 99.90 531.71 15.0563 325.85 99.32 438.93 12.4291 327.80 99.91 533.27 15.1005 325.90 99.33 440.10 12.4622 327.85 99.93 536.41 15.1894 325.95 99.35 443.95 12.5713 327.90 99.94 537.97 15.2336 326.00 99.36 445.62 12.6185 327.95 99.96 541.11 15.3225


34


in Feet

in Metre

in Mcft

in MM³ in

Feet in

Metre in

Mcft in MM³

328.00 99.97 542.68 15.3670 329.95 100.57 652.85 18.4866 328.05 99.99 545.81 15.4556 330.00 100.58 654.74 18.5402 328.10 100.00 547.38 15.5001 330.05 100.60 658.53 18.6475 328.15 100.02 551.04 15.6037 330.10 100.61 660.48 18.7027 328.20 100.04 554.71 15.7076 330.15 100.63 664.38 18.8131 328.25 100.05 556.54 15.7594 330.20 100.64 666.33 18.8683 328.30 100.07 560.21 15.8634 330.25 100.66 670.23 18.9788 328.35 100.08 562.04 15.9152 330.30 100.68 674.13 19.0892 328.40 100.10 565.71 16.0191 330.35 100.69 676.08 19.1444 328.45 100.11 567.54 16.0709 330.40 100.71 679.98 19.2549 328.50 100.13 571.20 16.1746 330.45 100.72 681.94 19.3104 328.55 100.14 573.04 16.2267 330.50 100.74 685.84 19.4208 328.60 100.16 576.70 16.3303 330.55 100.75 687.79 19.4760 328.65 100.17 578.54 16.3824 330.60 100.77 691.69 19.5865 328.70 100.19 582.20 16.4861 330.65 100.78 693.64 19.6417 328.75 100.20 584.03 16.5379 330.70 100.80 697.54 19.7521 328.80 100.22 587.70 16.6418 330.75 100.81 699.49 19.8073 328.85 100.23 589.53 16.6936 330.80 100.83 703.39 19.9178 328.90 100.25 593.19 16.7973 330.85 100.84 705.34 19.9730 328.95 100.26 595.03 16.8494 330.90 100.86 709.25 20.0837 329.00 100.28 598.69 16.9530 330.95 100.87 711.19 20.1386 329.05 100.29 600.53 17.0051 331.00 100.89 715.09 20.2491 329.10 100.31 604.19 17.1087 331.05 100.90 717.05 20.3046 329.15 100.32 606.03 17.1608 331.10 100.92 720.95 20.4150 329.20 100.34 609.69 17.2645 331.15 100.93 722.90 20.4702 329.25 100.36 613.36 17.3684 331.20 100.95 726.10 20.5608 329.30 100.37 615.19 17.4202 331.25 100.97 730.70 20.6911 329.35 100.39 618.86 17.5241 331.30 100.98 732.65 20.7463 329.40 100.40 620.69 17.5760 331.35 101.00 736.56 20.8570 329.45 100.42 624.47 17.6830 331.40 101.01 738.64 20.9159 329.50 100.43 626.37 17.7368 331.45 101.03 742.82 21.0343 329.55 100.45 630.15 17.8438 331.50 101.04 744.91 21.0935 329.60 100.46 632.04 17.8974 331.55 101.06 749.08 21.2116 329.65 100.48 635.83 18.0047 331.60 101.07 751.17 21.2707 329.70 100.49 637.72 18.0582 331.65 101.09 755.34 21.3888 329.75 100.51 641.50 18.1652 331.70 101.10 757.43 21.4480 329.80 100.52 643.39 18.2188 331.75 101.12 761.61 21.5664 329.85 100.54 647.18 18.3261 331.80 101.13 763.69 21.6253 329.90 100.55 649.07 18.3796 331.85 101.15 767.87 21.7436


35


in Feet

in Metre

in Mcft

in MM³ in

Feet in

Metre in Mcft in MM³

331.90 101.16 769.96 21.8028 333.85 101.76 902.91 25.5675 331.95 101.18 774.13 21.9209 333.90 101.77 905.29 25.6349 332.00 101.19 776.22 21.9801 333.95 101.79 910.06 25.7700 332.05 101.21 780.39 22.0982 334.00 101.80 912.44 25.8374 332.10 101.22 782.48 22.1573 334.05 101.82 917.21 25.9725 332.15 101.24 786.66 22.2757 334.10 101.83 919.59 26.0399 332.20 101.25 788.74 22.3346 334.15 101.85 924.36 26.1749 332.25 101.27 792.92 22.4530 334.20 101.86 926.75 26.2426 332.30 101.29 797.09 22.5711 334.25 101.88 931.51 26.3774 332.35 101.30 799.18 22.6302 334.30 101.89 933.89 26.4448 332.40 101.32 803.36 22.7486 334.35 101.91 938.66 26.5799 332.45 101.33 805.44 22.8075 334.40 101.93 943.43 26.7149 332.50 101.35 809.62 22.9259 334.45 101.94 945.82 26.7826 332.55 101.36 811.71 22.9850 334.50 101.96 950.58 26.9174 332.60 101.38 815.88 23.1031 334.55 101.97 952.97 26.9851 332.65 101.39 817.97 23.1623 334.60 101.99 957.73 27.1199 332.70 101.41 822.14 23.2804 334.65 102.00 960.12 27.1875 332.75 101.42 824.23 23.3396 334.70 102.02 965.29 27.3339 332.80 101.44 828.41 23.4579 334.75 102.03 967.88 27.4073 332.85 101.45 830.49 23.5168 334.80 102.05 973.05 27.5537 332.90 101.47 834.67 23.6352 334.85 102.06 975.64 27.6270 332.95 101.48 836.76 23.6944 334.90 102.08 980.81 27.7734 333.00 101.50 840.93 23.8125 334.95 102.09 983.39 27.8465 333.05 101.51 843.32 23.8801 335.00 102.11 988.57 27.9932 333.10 101.53 848.08 24.0149 335.05 102.12 991.16 28.0665 333.15 101.54 850.47 24.0826 335.10 102.14 996.33 28.2129 333.20 101.56 855.23 24.2174 335.15 102.15 998.92 28.2862 333.25 101.57 857.62 24.2851 335.20 102.17 1004.09 28.4326 333.30 101.59 862.38 24.4199 335.25 102.18 1006.68 28.5060 333.35 101.61 867.15 24.5549 335.30 102.20 1011.85 28.6524 333.40 101.62 869.54 24.6226 335.35 102.21 1014.44 28.7257 333.45 101.64 874.30 24.7574 335.40 102.23 1019.61 28.8721 333.50 101.65 876.69 24.8251 335.45 102.25 1024.79 29.0188 333.55 101.67 881.45 24.9599 335.50 102.26 1027.38 29.0921 333.60 101.68 883.84 25.0275 335.55 102.28 1032.55 29.2385 333.65 101.70 888.61 25.1626 335.60 102.29 1035.14 29.3119 333.70 101.71 890.99 25.2300 335.65 102.31 1040.31 29.4583 333.75 101.73 895.76 25.3651 335.70 102.32 1042.89 29.5313 333.80 101.74 898.14 25.4325 335.75 102.34 1048.07 29.6780


36


Feet in


in Feet

in Metre

in Mcft in MM³

335.80 102.35 1050.66 29.7514 337.95 103.01 1230.29 34.8379 335.85 102.37 1055.83 29.8977 338.00 103.02 1233.05 34.9161 335.90 102.38 1058.42 29.9711 338.05 103.04 1238.59 35.0729 335.95 102.40 1063.59 30.1175 338.10 103.05 1241.36 35.1514 336.00 102.41 1066.18 30.1908 338.15 103.07 1246.89 35.3080 336.05 102.43 1071.35 30.3372 338.20 103.08 1249.66 35.3864 336.10 102.44 1073.94 30.4106 338.25 103.10 1255.20 35.5433 336.15 102.46 1079.11 30.5570 338.30 103.11 1257.97 35.6217 336.20 102.47 1081.69 30.6300 338.35 103.13 1263.52 35.7789 336.25 102.49 1086.87 30.7767 338.40 103.14 1266.30 35.8576 336.30 102.50 1089.46 30.8500 338.45 103.16 1271.85 36.0147 336.35 102.52 1094.98 31.0064 338.50 103.17 1274.63 36.0935 336.40 102.53 1097.74 31.0845 338.55 103.19 1280.18 36.2506 336.45 102.55 1103.26 31.2408 338.60 103.21 1285.73 36.4078 336.50 102.57 1108.78 31.3971 338.65 103.22 1288.51 36.4865 336.55 102.58 1111.53 31.4750 338.70 103.24 1294.06 36.6437 336.60 102.60 1117.05 31.6313 338.75 103.25 1296.84 36.7224 336.65 102.61 1119.81 31.7095 338.80 103.27 1302.39 36.8795 336.70 102.63 1125.33 31.8658 338.85 103.28 1305.17 36.9583 336.75 102.64 1128.09 31.9439 338.90 103.30 1310.72 37.1154 336.80 102.66 1133.61 32.1002 338.95 103.31 1313.49 37.1939 336.85 102.67 1136.37 32.1784 339.00 103.33 1319.05 37.3513 336.90 102.69 1141.89 32.3347 339.05 103.34 1321.82 37.4297 336.95 102.70 1144.65 32.4128 339.10 103.36 1327.37 37.5869 337.00 102.72 1150.17 32.5692 339.15 103.37 1330.15 37.6656 337.05 102.73 1152.93 32.6473 339.20 103.39 1335.70 37.8228 337.10 102.75 1158.45 32.8036 339.25 103.40 1338.48 37.9015 337.15 102.76 1161.21 32.8818 339.30 103.42 1344.69 38.0773 337.20 102.78 1166.73 33.0381 339.35 103.43 1347.81 38.1657 337.25 102.79 1169.49 33.1162 339.40 103.45 1354.03 38.3418 337.30 102.81 1175.01 33.2725 339.45 103.46 1357.13 38.4296 337.35 102.82 1177.76 33.3504 339.50 103.48 1363.35 38.6057 337.40 102.84 1183.28 33.5067 339.55 103.49 1366.46 38.6938 337.45 102.85 1186.04 33.5849 339.60 103.51 1372.68 38.8699 337.50 102.87 1191.56 33.7412 339.65 103.53 1378.90 39.0461 337.55 102.89 1197.09 33.8978 339.70 103.54 1382.01 39.1341 337.60 102.90 1199.84 33.9757 339.75 103.56 1388.23 39.3103 337.65 102.92 1205.38 34.1325 339.80 103.57 1391.34 39.3983 337.70 102.93 1208.14 34.2107 339.85 103.59 1397.56 39.5745 337.75 102.95 1213.68 34.3676 339.90 103.60 1400.67 39.6625 337.80 102.96 1216.45 34.4460 339.95 103.62 1407.56 39.8576 337.85 102.98 1221.98 34.6026 340.00 103.63 1410.99 39.9547 337.90 102.99 1224.75 34.6810 340.05 103.65 1417.89 40.1501


37


Feet in


in Feet

in Metre

in Mcft in MM³

340.10 103.66 1421.33 40.2475 342.25 104.32 1637.92 46.3807 340.15 103.68 1428.21 40.4424 342.30 104.33 1641.09 46.4704 340.20 103.69 1431.66 40.5401 342.35 104.35 1647.32 46.6469 340.25 103.71 1438.54 40.7349 342.40 104.36 1650.43 46.7349 340.30 103.72 1441.99 40.8326 342.45 104.38 1656.66 46.9113 340.35 103.74 1448.87 41.0274 342.50 104.39 1659.77 46.9994 340.40 103.75 1452.32 41.1251 342.55 104.41 1665.99 47.1755 340.45 103.77 1459.20 41.3199 342.60 104.42 1669.11 47.2639 340.50 103.78 1462.65 41.4176 342.65 104.44 1675.33 47.4400 340.55 103.80 1469.53 41.6124 342.70 104.45 1678.44 47.5281 340.60 103.81 1472.87 41.7070 342.75 104.47 1684.67 47.7045 340.65 103.83 1479.53 41.8956 342.80 104.49 1690.89 47.8806 340.70 103.85 1486.19 42.0842 342.85 104.50 1694.00 47.9687 340.75 103.86 1489.53 42.1788 342.90 104.52 1701.37 48.1774 340.80 103.88 1496.19 42.3673 342.95 104.53 1705.06 48.2819 340.85 103.89 1499.53 42.4619 343.00 104.55 1712.42 48.4903 340.90 103.91 1506.19 42.6505 343.05 104.56 1716.11 48.5948 340.95 103.92 1509.53 42.7451 343.10 104.58 1723.48 48.8035 341.00 103.94 1516.19 42.9337 343.15 104.59 1727.17 48.9080 341.05 103.95 1519.53 43.0283 343.20 104.61 1734.54 49.1167 341.10 103.97 1526.19 43.2168 343.25 104.62 1738.22 49.2209 341.15 103.98 1529.52 43.3111 343.30 104.64 1745.59 49.4296 341.20 104.00 1536.19 43.5000 343.35 104.65 1749.28 49.5340 341.25 104.01 1539.52 43.5943 343.40 104.67 1756.65 49.7427 341.30 104.03 1546.19 43.7832 343.45 104.68 1760.33 49.8469 341.35 104.04 1549.52 43.8775 343.50 104.70 1767.70 50.0556 341.40 104.06 1556.19 44.0664 343.55 104.71 1771.39 50.1601 341.45 104.07 1559.52 44.1606 343.60 104.73 1778.76 50.3688 341.50 104.09 1566.18 44.3492 343.65 104.74 1782.44 50.4730 341.55 104.10 1569.52 44.4438 343.70 104.76 1789.81 50.6817 341.60 104.12 1575.74 44.6199 343.75 104.78 1797.18 50.8904 341.65 104.13 1578.85 44.7080 343.80 104.79 1800.86 50.9946 341.70 104.15 1585.08 44.8844 343.85 104.81 1808.24 51.2036 341.75 104.17 1591.30 45.0606 343.90 104.82 1811.92 51.3078 341.80 104.18 1594.42 45.1489 343.95 104.84 1819.29 51.5165 341.85 104.20 1600.64 45.3250 344.00 104.85 1822.98 51.6210 341.90 104.21 1603.75 45.4131 344.05 104.87 1830.35 51.8297 341.95 104.23 1609.98 45.5895 344.10 104.88 1834.03 51.9339 342.00 104.24 1613.09 45.6776 344.15 104.90 1841.40 52.1426 342.05 104.26 1619.31 45.8537 344.20 104.91 1845.09 52.2471 342.10 104.27 1622.42 45.9418 344.25 104.93 1852.46 52.4558 342.15 104.29 1628.65 46.1182 344.30 104.94 1856.14 52.5600 342.20 104.30 1631.76 46.2063 344.35 104.96 1863.51 52.7687


38


Feet in


in Feet

in Metre

in Mcft in MM³

344.40 104.97 1867.19 52.8729 346.55 105.63 2124.87 60.1696 344.45 104.99 1874.57 53.0819 346.60 105.64 2128.79 60.2806 344.50 105.00 1878.25 53.1861 346.65 105.66 2136.66 60.5034 344.55 105.02 1886.08 53.4078 346.70 105.67 2140.57 60.6141 344.60 105.03 1889.99 53.5185 346.75 105.69 2148.42 60.8364 344.65 105.05 1897.81 53.7399 346.80 105.70 2152.34 60.9474 344.70 105.06 1901.73 53.8509 346.85 105.72 2160.19 61.1697 344.75 105.08 1909.55 54.0724 346.90 105.74 2168.04 61.3920 344.80 105.10 1917.37 54.2938 346.95 105.75 2171.96 61.5030 344.85 105.11 1921.28 54.4045 347.00 105.77 2179.81 61.7253 344.90 105.13 1929.11 54.6263 347.05 105.78 2183.74 61.8366 344.95 105.14 1933.02 54.7370 347.10 105.80 2191.59 62.0589 345.00 105.16 1940.85 54.9587 347.15 105.81 2195.51 62.1699 345.05 105.17 1944.76 55.0694 347.20 105.83 2203.36 62.3921 345.10 105.19 1952.58 55.2909 347.25 105.84 2207.28 62.5032 345.15 105.20 1945.49 55.0901 347.30 105.86 2215.13 62.7254 345.20 105.22 1964.32 55.6233 347.35 105.87 2219.06 62.8367 345.25 105.23 1968.23 55.7340 347.40 105.89 2226.91 63.0590 345.30 105.25 1976.05 55.9555 347.45 105.90 2230.83 63.1700 345.35 105.26 1979.77 56.0608 347.50 105.92 2239.06 63.4031 345.40 105.28 1987.79 56.2879 347.55 105.93 2243.17 63.5194 345.45 105.29 1991.70 56.3986 347.60 105.95 2251.40 63.7525 345.50 105.31 1999.53 56.6203 347.65 105.96 2255.51 63.8689 345.55 105.32 2003.44 56.7310 347.70 105.98 2263.74 64.1019 345.60 105.34 2010.26 56.9242 347.75 105.99 2267.80 64.2169 345.65 105.35 2015.15 57.0626 347.80 106.01 2276.09 64.4516 345.70 105.37 2022.99 57.2846 347.85 106.02 2280.20 64.5680 345.75 105.38 2026.19 57.3753 347.90 106.04 2288.43 64.8011 345.80 105.40 2034.73 57.6171 347.95 106.06 2296.66 65.0341 345.85 105.42 2042.57 57.8391 348.00 106.07 2300.77 65.1505 345.90 105.43 2046.49 57.9501 348.05 106.09 2308.99 65.3833 345.95 105.45 2054.33 58.1721 348.10 106.10 2313.11 65.4999 346.00 105.46 2058.24 58.2828 348.15 106.12 2321.72 65.7437 346.05 105.48 2066.08 58.5048 348.20 106.13 2326.02 65.8655 346.10 105.49 2069.99 58.6155 348.25 106.15 2334.63 66.1093 346.15 105.51 2077.84 58.8378 348.30 106.16 2338.94 66.2313 346.20 105.52 2081.76 58.9488 348.35 106.18 2347.54 66.4749 346.25 105.54 2089.59 59.1705 348.40 106.19 2351.85 66.5969 346.30 105.55 2093.51 59.2815 348.45 106.21 2360.46 66.8407 346.35 105.57 2101.34 59.5033 348.50 106.22 2364.76 66.9625 346.40 105.58 2105.26 59.6143 348.55 106.24 2373.37 67.2063 346.45 105.60 2113.10 59.8363 348.60 106.25 2377.67 67.3281 346.50 105.61 2117.02 59.9473 348.65 106.27 2386.28 67.5719


39


Feet in

Metre in Mcft in MM³ in

Feet in


348.70 106.28 2390.58 67.6936 350.85 106.94 2668.65 75.5677 348.75 106.30 2399.19 67.9374 350.90 106.95 2672.82 75.6858 348.80 106.31 2403.49 68.0592 350.95 106.97 2681.15 75.9216 348.85 106.33 2412.10 68.3030 351.00 106.98 2685.32 76.0397 348.90 106.34 2416.41 68.4250 351.05 107.00 2693.65 76.2756 348.95 106.36 2425.02 68.6689 351.10 107.02 2703.44 76.5528 349.00 106.38 2433.62 68.9124 351.15 107.03 2708.33 76.6913 349.05 106.39 2437.93 69.0344 351.20 107.05 2718.11 76.9682 349.10 106.41 2446.54 69.2782 351.25 107.06 2722.99 77.1064 349.15 106.42 2450.84 69.4000 351.30 107.08 2732.78 77.3836 349.20 106.44 2459.45 69.6438 351.35 107.09 2737.67 77.5221 349.25 106.45 2463.75 69.7656 351.40 107.11 2747.45 77.7990 349.30 106.47 2472.36 70.0094 351.45 107.12 2752.34 77.9375 349.35 106.48 2476.66 70.1311 351.50 107.14 2762.12 78.2145 349.40 106.50 2485.27 70.3749 351.55 107.15 2767.01 78.3529 349.45 106.51 2489.44 70.4930 351.60 107.17 2776.79 78.6299 349.50 106.53 2497.77 70.7289 351.65 107.18 2781.69 78.7686 349.55 106.54 2501.94 70.8470 351.70 107.20 2791.47 79.0456 349.60 106.56 2510.28 71.0831 351.75 107.21 2796.36 79.1840 349.65 106.57 2514.45 71.2012 351.80 107.23 2806.14 79.4610 349.70 106.59 2522.78 71.4371 351.85 107.24 2811.03 79.5994 349.75 106.60 2526.95 71.5552 351.90 107.26 2820.81 79.8764 349.80 106.62 2535.28 71.7911 351.95 107.27 2825.69 80.0146 349.85 106.63 2539.45 71.9091 352.00 107.29 2835.48 80.2918 349.90 106.65 2547.79 72.1453 352.05 107.30 2840.37 80.4302 349.95 106.66 2551.95 72.2631 352.10 107.32 2850.15 80.7072 350.00 106.68 2560.29 72.4993 352.15 107.34 2859.93 80.9841 350.05 106.70 2568.62 72.7351 352.20 107.35 2864.82 81.1226 350.10 106.71 2572.79 72.8532 352.25 107.37 2874.63 81.4004 350.15 106.73 2581.13 73.0894 352.30 107.38 2879.49 81.5380 350.20 106.74 2585.29 73.2072 352.35 107.40 2889.28 81.8152 350.25 106.76 2593.63 73.4434 352.40 107.41 2894.17 81.9537 350.30 106.77 2597.79 73.5612 352.45 107.43 2903.95 82.2306 350.35 106.79 2606.13 73.7973 352.50 107.44 2908.84 82.3691 350.40 106.80 2610.30 73.9154 352.55 107.46 2918.62 82.6460 350.45 106.82 2618.64 74.1516 352.60 107.47 2923.51 82.7845 350.50 106.83 2622.80 74.2694 352.65 107.49 2933.29 83.0614 350.55 106.85 2631.14 74.5055 352.70 107.50 2938.18 83.1999 350.60 106.86 2635.31 74.6236 352.75 107.52 2947.97 83.4771 350.65 106.88 2643.64 74.8595 352.80 107.53 2952.86 83.6156 350.70 106.89 2647.81 74.9776 352.85 107.55 2962.64 83.8925 350.75 106.91 2656.14 75.2134 352.90 107.56 2967.53 84.0310 350.80 106.92 2660.31 75.3315 352.95 107.58 2977.31 84.3080


40


in Feet

in Metre

in Mcft in MM³ in

Feet in


353.00 107.59 2982.20 84.4464 355.15 108.25 3305.24 93.5939 353.05 107.61 2991.98 84.7234 355.20 108.26 3310.14 93.7326 353.10 107.62 2996.88 84.8621 355.25 108.28 3319.93 94.0099 353.15 107.64 3006.66 85.1390 355.30 108.30 3329.73 94.2874 353.20 107.66 3016.44 85.4160 355.40 108.33 3344.43 94.7036 353.25 107.67 3021.33 85.5545 355.45 108.34 3349.33 94.8424 353.30 107.69 3031.11 85.8314 355.50 108.36 3353.13 94.9500 353.35 107.70 3036.00 85.9699 355.55 108.37 3364.03 95.2586 353.40 107.72 3045.79 86.2471 355.60 108.39 3373.83 95.5361 353.45 107.73 3050.68 86.3856 355.65 108.40 3378.73 95.6749 353.50 107.75 3060.46 86.6625 355.70 108.42 3388.75 95.9586 353.55 107.76 3065.35 86.8010 355.75 108.43 3393.76 96.1005 353.60 107.78 3075.13 87.0779 355.80 108.45 3403.78 96.3842 353.65 107.79 3080.02 87.2164 355.85 108.46 3408.79 96.5261 353.70 107.81 3089.81 87.4936 355.90 108.48 3418.80 96.8095 353.75 107.82 3094.69 87.6318 355.95 108.49 3423.81 96.9514 353.80 107.84 3104.48 87.9090 356.00 108.51 3433.83 97.2351 353.85 107.85 3109.37 88.0475 356.05 108.52 3438.84 97.3770 353.90 107.87 3119.15 88.3244 356.10 108.54 3448.86 97.6607 353.95 107.88 3124.04 88.4629 356.15 108.55 3453.86 97.8023 354.00 107.90 3133.83 88.7401 356.20 108.57 3463.88 98.0861 354.05 107.91 3138.72 88.8786 356.25 108.59 3473.89 98.3695 354.10 107.93 3148.49 89.1552 356.30 108.60 3478.91 98.5117 354.15 107.94 3153.39 89.2940 356.35 108.62 3489.14 98.8013 354.20 107.96 3163.17 89.5709 356.40 108.63 3494.26 98.9463 354.25 107.98 3172.96 89.8481 356.45 108.65 3504.49 99.2360 354.30 107.99 3177.84 89.9863 356.50 108.66 3509.61 99.3810 354.35 108.01 3182.74 90.1251 356.55 108.68 3519.85 99.6710 354.40 108.02 3192.54 90.4026 356.60 108.69 3524.97 99.8159 354.45 108.04 3202.34 90.6801 356.65 108.71 3535.20 100.1056 354.50 108.05 3207.24 90.8188 356.70 108.72 3540.32 100.2506 354.55 108.07 3217.04 91.0963 356.75 108.74 3550.55 100.5403 354.60 108.08 3221.94 91.2351 356.80 108.75 3555.67 100.6853 354.65 108.10 3231.74 91.5126 356.85 108.77 3565.91 100.9752 354.70 108.11 3236.64 91.6514 356.90 108.78 3571.02 101.1199 354.75 108.13 3246.44 91.9289 356.95 108.80 3581.26 101.4099 354.80 108.14 3252.34 92.0959 357.00 108.81 3586.38 101.5549 354.85 108.16 3261.14 92.3451 357.05 108.83 3596.61 101.8446 354.90 108.17 3266.04 92.4839 357.10 108.84 3601.73 101.9895 354.95 108.19 3275.84 92.7614 357.15 108.86 3611.96 102.2792 355.00 108.20 3280.74 92.9001 357.20 108.87 3617.08 102.4242 355.05 108.22 3290.54 93.1776 357.25 108.89 3627.32 102.7142 355.10 108.23 3295.44 93.3164 357.30 108.91 3637.55 103.0038


41


Feet in


in Feet

in Metre

in Mcft in MM³

357.35 108.92 3642.67 103.1488 359.30 109.51 3982.71 112.7777 357.40 108.94 3652.90 103.4385 359.35 109.53 3994.38 113.1081 357.45 108.95 3658.03 103.5838 359.40 109.55 4006.06 113.4389 357.50 108.97 3668.26 103.8735 359.45 109.56 4011.89 113.6040 357.55 108.98 3673.38 104.0184 359.50 109.58 4023.56 113.9344 357.60 109.00 3683.61 104.3081 359.55 109.59 4029.39 114.0995 357.65 109.01 3689.48 104.4743 359.60 109.61 4041.07 114.4303 357.70 109.03 3701.21 104.8065 359.65 109.62 4046.91 114.5956 357.75 109.04 3707.07 104.9724 359.70 109.64 4058.58 114.9261 357.80 109.06 3718.80 105.3046 359.75 109.65 4064.41 115.0912 357.85 109.07 3724.67 105.4708 359.80 109.67 4076.08 115.4216 357.90 109.09 3736.39 105.8027 359.85 109.68 4081.92 115.5870 357.95 109.10 3742.26 105.9689 359.90 109.70 4093.59 115.9175 358.00 109.12 3753.99 106.3011 359.95 109.71 4099.43 116.0828 358.05 109.13 3759.86 106.4673 360.00 109.73 4111.10 116.4133 358.10 109.15 3771.59 106.7994 360.05 109.74 4116.93 116.5784 358.15 109.16 3777.46 106.9657 360.10 109.76 4122.77 116.7437 358.20 109.18 3789.19 107.2978 360.15 109.77 4134.44 117.0742 358.25 109.19 3795.05 107.4637 360.20 109.79 4146.11 117.4047 358.30 109.21 3806.78 107.7959 360.25 109.80 4151.95 117.5700 358.35 109.23 3818.51 108.1281 360.30 109.82 4163.62 117.9005 358.40 109.24 3824.38 108.2943 360.35 109.83 4169.46 118.0658 358.45 109.26 3836.11 108.6264 360.40 109.85 4181.13 118.3963 358.50 109.27 3841.97 108.7924 360.45 109.87 4192.80 118.7268 358.55 109.29 3853.70 109.1245 360.50 109.88 4198.64 118.8921 358.60 109.30 3859.57 109.2907 360.55 109.90 4210.31 119.2226 358.65 109.32 3871.30 109.6229 360.60 109.91 4216.14 119.3877 358.70 109.33 3877.17 109.7891 360.65 109.93 4227.81 119.7181 358.75 109.35 3888.89 110.1210 360.70 109.94 4233.65 119.8835 358.80 109.36 3894.76 110.2872 360.75 109.96 4245.32 120.2140 358.85 109.38 3906.49 110.6194 360.80 109.97 4251.16 120.3793 358.90 109.39 3912.36 110.7856 360.85 109.99 4262.83 120.7098 358.95 109.41 3924.09 111.1177 360.90 110.00 4268.66 120.8749 359.00 109.42 3929.95 111.2837 360.95 110.02 4280.67 121.2150 359.05 109.44 3941.68 111.6158 361.00 110.03 4286.67 121.3849 359.10 109.45 3947.55 111.7821 361.05 110.05 4292.68 121.5550 359.15 109.47 3959.28 112.1142 361.10 110.06 4304.69 121.8951 359.20 109.48 3965.15 112.2804 361.15 110.08 4316.69 122.2349 359.25 109.50 3976.88 112.6126 361.20 110.09 4322.69 122.4048


42


Feet in


in Feet

in Metre

in Mcft in MM³

361.25 110.11 4334.70 122.7449 363.30 110.73 4704.34 133.2119 361.30 110.12 4340.71 122.9151 363.35 110.75 4716.12 133.5455 361.35 110.14 4352.71 123.2549 363.40 110.76 4721.42 133.6956 361.40 110.15 4358.72 123.4251 363.45 110.78 4733.80 134.0462 361.45 110.17 4370.72 123.7649 363.50 110.79 4739.69 134.2129 361.50 110.19 4382.73 124.1050 363.55 110.81 4751.47 134.5465 361.55 110.20 4388.73 124.2749 363.60 110.83 4763.25 134.8801 361.60 110.22 4400.74 124.6150 363.65 110.84 4769.15 135.0472 361.65 110.23 4406.74 124.7849 363.70 110.86 4780.93 135.3807 361.70 110.25 4418.75 125.1249 363.75 110.87 4786.82 135.5475 361.75 110.26 4424.76 125.2951 363.80 110.89 4798.60 135.8811 361.80 110.28 4436.76 125.6349 363.85 110.90 4804.49 136.0479 361.85 110.29 4442.77 125.8051 363.90 110.92 4816.28 136.3817 361.90 110.31 4454.77 126.1449 363.95 110.93 4822.17 136.5485 361.95 110.32 4460.78 126.3151 364.00 110.95 4828.06 136.7153 362.00 110.34 4472.78 126.6549 364.05 110.96 4839.84 137.0489 362.05 110.35 4478.79 126.8251 364.10 110.98 4851.62 137.3824 362.10 110.37 4490.79 127.1649 364.15 110.99 4863.41 137.7163 362.15 110.38 4496.79 127.3348 364.20 111.01 4869.26 137.8820 362.20 110.40 4508.80 127.6749 364.25 111.02 4875.11 138.0476 362.25 110.41 4514.75 127.8434 364.30 111.04 4886.81 138.3789 362.30 110.43 4526.65 128.1803 364.35 111.05 4892.66 138.5446 362.35 110.44 4532.59 128.3485 364.40 111.07 4904.36 138.8759 362.40 110.46 4544.49 128.6855 364.45 111.08 4910.21 139.0415 362.45 110.47 4550.44 128.8540 364.50 111.10 4916.06 139.2072 362.50 110.49 4562.33 129.1907 364.55 111.11 4929.88 139.5985 362.55 110.51 4574.23 129.5276 364.60 111.13 4945.82 140.0499 362.60 110.52 4580.17 129.6958 364.65 111.15 4961.76 140.5013 362.65 110.54 4592.07 130.0328 364.70 111.16 4969.73 140.7269 362.70 110.55 4598.02 130.2013 364.75 111.18 4985.67 141.1783 362.75 110.57 4609.91 130.5380 364.80 111.19 4993.64 141.4040 362.80 110.58 4615.86 130.7065 364.85 111.21 5008.52 141.8254 362.85 110.60 4627.75 131.0432 364.90 111.22 5015.43 142.0210 362.90 110.61 4633.64 131.2099 364.95 111.24 5029.25 142.4124 362.95 110.63 4645.43 131.5438 365.00 111.25 5036.16 142.6080 363.00 110.64 4651.32 131.7106 365.05 111.27 5049.98 142.9994 363.05 110.66 4663.10 132.0442 365.10 111.28 5056.89 143.1950 363.10 110.67 4668.99 132.2109 365.15 111.30 5070.71 143.5864 363.15 110.69 4680.77 132.5445 365.20 111.31 5077.62 143.7821 363.20 110.70 4686.67 132.7116 365.25 111.33 5091.44 144.1734 363.25 110.72 4698.45 133.0452 365.30 111.34 5098.35 144.3691


43


in Feet

in Metre

in Mcft in MM³ in

Feet in


365.35 111.36 5112.18 144.7607 367.30 111.95 5504.89 155.8810 365.40 111.37 5119.09 144.9563 367.35 111.97 5518.09 156.2548 365.45 111.39 5133.26 145.3576 367.40 111.98 5524.63 156.4400 365.50 111.40 5139.82 145.5434 367.45 112.00 5537.79 156.8126 365.55 111.42 5153.64 145.9347 367.50 112.01 5544.54 157.0037 365.60 111.43 5160.55 146.1304 367.55 112.03 5558.05 157.3863 365.65 111.45 5174.37 146.5217 367.60 112.04 5564.80 157.5774 365.70 111.47 5188.19 146.9130 367.65 112.06 5578.31 157.9600 365.75 111.48 5195.10 147.1087 367.70 112.07 5585.06 158.1511 365.80 111.50 5208.92 147.5000 367.75 112.09 5598.57 158.5337 365.85 111.51 5215.50 147.6864 367.80 112.11 5612.08 158.9163 365.90 111.53 5228.65 148.0587 367.85 112.12 5618.83 159.1074 365.95 111.54 5235.23 148.2451 367.90 112.14 5632.34 159.4900 366.00 111.56 5248.38 148.6174 367.95 112.15 5639.09 159.6811 366.05 111.57 5254.96 148.8038 368.00 112.17 5652.60 160.0637 366.10 111.59 5268.11 149.1761 368.05 112.18 5659.39 160.2559 366.15 111.60 5274.69 149.3624 368.10 112.20 5672.87 160.6376 366.20 111.62 5287.85 149.7351 368.15 112.21 5679.62 160.8288 366.25 111.63 5294.42 149.9211 368.20 112.23 5693.13 161.2113 366.30 111.65 5307.58 150.2938 368.25 112.24 5699.88 161.4025 366.35 111.66 5314.16 150.4801 368.30 112.26 5713.39 161.7850 366.40 111.68 5327.31 150.8525 368.35 112.27 5720.14 161.9762 366.45 111.69 5333.89 151.0388 368.40 112.29 5733.65 162.3587 366.50 111.71 5347.04 151.4112 368.45 112.30 5740.41 162.5502 366.55 111.72 5353.62 151.5975 368.50 112.32 5753.91 162.9324 366.60 111.74 5366.78 151.9701 368.55 112.33 5760.67 163.1239 366.65 111.75 5373.35 152.1562 368.60 112.35 5774.17 163.5061 366.70 111.77 5386.51 152.5288 368.65 112.36 5780.93 163.6976 366.75 111.79 5399.66 152.9012 368.70 112.38 5794.44 164.0801 366.80 111.80 5406.24 153.0875 368.75 112.40 5807.94 164.4624 366.85 111.82 5419.39 153.4599 368.80 112.41 5814.69 164.6535 366.90 111.83 5425.97 153.6462 368.85 112.43 5828.21 165.0364 366.95 111.85 5439.13 154.0189 368.90 112.44 5834.96 165.2275 367.00 111.86 5445.70 154.2049 368.95 112.46 5848.47 165.6101 367.05 111.88 5458.86 154.5776 369.00 112.47 5855.22 165.8012 367.10 111.89 5465.44 154.7639 369.05 112.49 5868.73 166.1838 367.15 111.91 5478.59 155.1362 369.10 112.50 5875.48 166.3749 367.20 111.92 5485.17 155.3226 369.15 112.52 5889.32 166.7668 367.25 111.94 5498.32 155.6949 369.20 112.53 5896.23 166.9625


44


in Feet

in Metre

in Mcft in MM³ in

Feet in


369.25 112.55 5910.06 167.3541 371.40 113.20 6372.55 180.4504 369.30 112.56 5916.98 167.5501 371.45 113.22 6387.68 180.8788 369.35 112.58 5930.81 167.9417 371.50 113.23 6395.24 181.0929 369.40 112.59 5937.73 168.1376 371.55 113.25 6410.37 181.5213 369.45 112.61 5951.56 168.5293 371.60 113.26 6417.93 181.7354 369.50 112.62 5958.48 168.7252 371.65 113.28 6433.06 182.1638 369.55 112.64 5972.31 169.1169 371.70 113.29 6440.62 182.3779 369.60 112.65 5979.23 169.3128 371.75 113.31 6455.74 182.8060 369.65 112.67 5993.06 169.7044 371.80 113.32 6463.31 183.0204 369.70 112.68 5999.98 169.9004 371.85 113.34 6478.43 183.4485 369.75 112.70 6013.81 170.2920 371.90 113.36 6493.56 183.8770 369.80 112.72 6027.64 170.6836 371.95 113.37 6501.12 184.0910 369.85 112.73 6034.56 170.8795 372.00 113.39 6516.25 184.5195 369.90 112.75 6048.39 171.2712 372.05 113.40 6523.81 184.7336 369.95 112.76 6055.31 171.4671 372.10 113.42 6538.96 185.1626 370.00 112.78 6069.14 171.8587 372.15 113.43 6546.54 185.3772 370.05 112.79 6076.06 172.0547 372.20 113.45 6561.69 185.8062 370.10 112.81 6089.89 172.4463 372.25 113.46 6569.18 186.0183 370.15 112.82 6096.81 172.6423 372.30 113.48 6584.43 186.4501 370.20 112.84 6110.64 173.0339 372.35 113.49 6592.01 186.6648 370.25 112.85 6117.56 173.2298 372.40 113.51 6607.16 187.0938 370.30 112.87 6131.39 173.6215 372.45 113.52 6614.74 187.3084 370.35 112.88 6138.31 173.8174 372.50 113.54 6629.89 187.7374 370.40 112.90 6152.14 174.2090 372.55 113.55 6637.47 187.9520 370.45 112.91 6159.05 174.4047 372.60 113.57 6652.63 188.3813 370.50 112.93 6172.89 174.7966 372.65 113.58 6660.21 188.5960 370.55 112.94 6179.80 174.9923 372.70 113.60 6675.36 189.0250 370.60 112.96 6193.64 175.3842 372.75 113.61 6682.95 189.2399 370.65 112.97 6200.55 175.5799 372.80 113.63 6690.55 189.4551 370.70 112.99 6214.39 175.9718 372.85 113.64 6705.73 189.8849 370.75 113.00 6221.30 176.1674 372.90 113.66 6720.92 190.3151 370.80 113.02 6236.43 176.5959 372.95 113.68 6736.10 190.7449 370.85 113.04 6251.55 177.0240 373.00 113.69 6743.69 190.9599 370.90 113.05 6259.12 177.2384 373.05 113.71 6758.88 191.3900 370.95 113.07 6274.24 177.6665 373.10 113.72 6766.47 191.6049 371.00 113.08 6281.80 177.8806 373.15 113.74 6781.66 192.0350 371.05 113.10 6296.93 178.3090 373.20 113.75 6789.25 192.2500 371.10 113.11 6304.49 178.5231 373.25 113.77 6804.44 192.6801 371.15 113.13 6319.62 178.9515 373.30 113.78 6812.03 192.8950 371.20 113.14 6327.18 179.1656 373.35 113.80 6827.21 193.3249 371.25 113.16 6342.30 179.5938 373.40 113.81 6834.81 193.5401 371.30 113.17 6349.87 179.8081 373.45 113.83 6849.99 193.9699 371.35 113.19 6364.99 180.2363 373.50 113.84 6857.59 194.1851


45


Feet in


in Feet

in Metre

in Mcft in MM³

373.55 113.86 6872.77 194.6150 375.60 114.48 7334.19 207.6809 373.60 113.87 6880.36 194.8299 375.65 114.50 7348.98 208.0997 373.65 113.89 6895.55 195.2600 375.70 114.51 7356.59 208.3152 373.70 113.90 6903.14 195.4750 375.75 114.53 7371.82 208.7465 373.75 113.92 6918.33 195.9051 375.80 114.54 7379.43 208.9620 373.80 113.93 6925.92 196.1200 375.85 114.56 7394.65 209.3930 373.85 113.95 6941.10 196.5499 375.90 114.57 7402.26 209.6085 373.90 113.96 6948.69 196.7648 375.95 114.59 7417.48 210.0394 373.95 113.98 6963.88 197.1949 376.00 114.60 7425.09 210.2549 374.00 114.00 6979.06 197.6248 376.05 114.62 7440.31 210.6859 374.05 114.01 6986.47 197.8346 376.10 114.64 7455.53 211.1169 374.10 114.03 7001.26 198.2534 376.15 114.65 7463.14 211.3324 374.15 114.04 7008.66 198.4630 376.20 114.67 7478.36 211.7634 374.20 114.06 7023.46 198.8821 376.25 114.68 7485.97 211.9789 374.25 114.07 7030.86 199.0916 376.30 114.70 7501.19 212.4098 374.30 114.09 7045.65 199.5104 376.35 114.71 7508.81 212.6256 374.35 114.10 7053.05 199.7199 376.40 114.73 7524.03 213.0566 374.40 114.12 7067.85 200.1390 376.45 114.74 7531.64 213.2721 374.45 114.13 7075.25 200.3486 376.50 114.76 7546.86 213.7031 374.50 114.15 7090.04 200.7674 376.55 114.77 7554.47 213.9186 374.55 114.16 7097.44 200.9769 376.60 114.79 7569.69 214.3495 374.60 114.18 7112.24 201.3960 376.65 114.80 7577.29 214.5648 374.65 114.19 7119.64 201.6056 376.70 114.82 7592.52 214.9960 374.70 114.21 7134.43 202.0244 376.75 114.83 7600.13 215.2115 374.75 114.22 7141.83 202.2339 376.80 114.85 7615.35 215.6425 374.80 114.24 7156.63 202.6530 376.85 114.86 7622.96 215.8580 374.85 114.25 7164.03 202.8625 376.90 114.88 7638.18 216.2890 374.90 114.27 7178.83 203.2816 376.95 114.89 7645.79 216.5045 374.95 114.28 7186.22 203.4909 377.00 114.91 7653.40 216.7199 375.00 114.30 7201.02 203.9100 377.05 114.92 7668.62 217.1509 375.05 114.32 7215.82 204.3291 377.10 114.94 7683.84 217.5819 375.10 114.33 7223.22 204.5386 377.15 114.96 7699.06 218.0129 375.15 114.35 7238.01 204.9574 377.20 114.97 7706.67 218.2284 375.20 114.36 7245.41 205.1670 377.25 114.99 7721.89 218.6594 375.25 114.38 7260.21 205.5861 377.30 115.00 7729.50 218.8749 375.30 114.39 7267.61 205.7956 377.35 115.02 7813.38 221.2501 375.35 114.41 7282.40 206.2144 377.40 115.03 7855.31 222.4374 375.40 114.42 7289.80 206.4240 377.45 115.05 7939.19 224.8126 375.45 114.44 7304.59 206.8428 377.50 115.06 7981.12 225.9999 375.50 114.45 7311.99 207.0523

375.55 114.47 7326.79 207.4714


46

2.1.2 Data of historicflood Known data of major flood occurred was in between 8th August 2018 and 16th August2018.Maximum discharge from spillway was 312.544 m3/sec on 16th August2018.

2.1.3 Latest design flood and flood routing study See AnnexureB 2.1.4 Sequence of operation of spillway gates during monsoon

Sequence operation of spillway gates as shownbelow

4th

2nd

1st

3rd

2.1.5 Discharge through spillway for different reservoir levels with different gateopenings


47

Table 2.2:Spillway Discharge Calculation 377.5 ft(115.05m)

h Q in Mm3 h Q in Mm3 h Q in Mm3 h Q in Mm3

0.1 0.0324 4.1 1.2366 8.1 2.2357 12.1 2.9733 0.2 0.0647 4.2 1.2643 8.2 2.2576 12.2 2.9875 0.3 0.0970 4.3 1.2917 8.3 2.2794 12.3 3.0014 0.4 0.1291 4.4 1.3192 8.4 2.3012 12.4 3.0150 0.5 0.1611 4.5 1.3464 8.5 2.3226 12.5 3.0284 0.6 0.1930 4.6 1.3735 8.6 2.3439 h : ft feet 0.7 0.2248 4.7 1.4005 8.7 2.3651 0.8 0.2565 4.8 1.4274 8.8 2.386 0.9 0.2880 4.9 1.4541 8.9 2.4068 1 0.3195 5 1.4808 9 2.4275

1.1 0.3508 5.1 1.5072 9.1 2.4480 1.2 0.3820 5.2 1.5335 9.2 2.4683 1.3 0.4131 5.3 1.5597 9.3 2.4883 1.4 0.4441 5.4 1.5858 9.4 2.5083 1.5 0.4750 5.5 1.6117 9.5 2.5280 1.6 0.5058 5.6 1.6375 9.6 2.5477 1.7 0.5365 5.7 1.6631 9.7 2.5670 1.8 0.567 5.8 1.6886 9.8 2.5862 1.9 0.5974 5.9 1.7140 9.9 2.6053 2 0.6277 6 1.7393 10 2.6241

2.1 0.6579 6.1 1.7644 10.1 2.6428 2.2 0.688 6.2 1.7894 10.2 2.6613 2.3 0.7179 6.3 1.8141 10.3 2.6796 2.4 0.7478 6.4 1.8388 10.4 2.6976 2.5 0.7775 6.5 1.8634 10.5 2.7156 2.6 0.8072 6.6 1.8877 10.6 2.7332 2.7 0.8366 6.7 1.9120 10.7 2.7508 2.8 0.866 6.8 1.9361 10.8 2.7681 2.9 0.8952 6.9 1.9600 10.9 2.7851 3 0.9244 7 1.9839 11 2.8020

3.1 0.9534 7.1 2.0075 11.1 2.8188 3.2 0.9822 7.2 2.0310 11.2 2.8352 3.3 1.011 7.3 2.0544 11.3 2.8514 3.4 1.0396 7.4 2.0776 11.4 2.8675 3.5 1.0682 7.5 2.1006 11.5 2.8833 3.6 1.0965 7.6 2.1236 11.6 2.8989 3.7 1.1248 7.7 2.1463 11.7 2.9142 3.8 1.153 7.8 2.1689 11.8 2.9294 3.9 1.181 7.9 2.1914 11.9 2.9443 4 1.2088 8 2.2136 12 2.9589


48

377 ft(114.91m) h Q in Mm3 h Q in Mm3 h Q in Mm3 h Q in Mm3

0.1 0.0319 4.1 1.2124 8.1 2.1828 12.1 2.8804 0.2 0.0637 4.2 1.2394 8.2 2.2039 12.2 2.8933 0.3 0.0953 4.3 1.2662 8.3 2.2249 12.3 2.9059 0.4 0.1269 4.4 1.293 8.4 2.2457 12.4 2.9182 0.5 0.1583 4.5 1.3196 8.5 2.2663 12.5 2.9302 0.6 0.1897 4.6 1.3461 8.6 2.2868

0.7 0.2209 4.7 1.3724 8.7 2.3071 0.8 0.252 4.8 1.3986 8.8 2.3273 0.9 0.283 4.9 1.4247 8.9 2.3471 1 0.3139 5 1.4506 9 2.3669

1.1 0.3447 5.1 1.4764 9.1 2.3865 1.2 0.3754 5.2 1.5021 9.2 2.406 1.3 0.4059 5.3 1.5275 9.3 2.4251 1.4 0.4364 5.4 1.5529 9.4 2.4442 1.5 0.4666 5.5 1.5782 9.5 2.4631 1.6 0.4968 5.6 1.6033 9.6 2.4817 1.7 0.5269 5.7 1.6283 9.7 2.5002 1.8 0.5569 5.8 1.653 9.8 2.5185 1.9 0.5867 5.9 1.6777 9.9 2.5366 2 0.6164 6 1.7023 10 2.5545

2.1 0.646 6.1 1.7267 10.1 2.5721 2.2 0.6755 6.2 1.7509 10.2 2.5897 2.3 0.7049 6.3 1.775 10.3 2.6069 2.4 0.7342 6.4 1.7989 10.4 2.624 2.5 0.7632 6.5 1.8227 10.5 2.641 2.6 0.7923 6.6 1.8465 10.6 2.6576 2.7 0.8211 6.7 1.8699 10.7 2.6741 2.8 0.8499 6.8 1.8932 10.8 2.6903 2.9 0.8785 6.9 1.9165 10.9 2.7063 3 0.9071 7 1.9395 11 2.7221

3.1 0.9354 7.1 1.9625 11.1 2.7377 3.2 0.9637 7.2 1.9852 11.2 2.7531 3.3 0.9918 7.3 2.0077 11.3 2.7682 3.4 1.0198 7.4 2.0302 11.4 2.7831 3.5 1.0478 7.5 2.0525 11.5 2.7978 3.6 1.0755 7.6 2.0746 11.6 2.8121 3.7 1.1031 7.7 2.0965 11.7 2.8263 3.8 1.1306 7.8 2.1184 11.8 2.8403 3.9 1.1581 7.9 2.14 11.9 2.8539 4 1.1853 8 2.1615 12 2.8673


49

376.5 ft(114.76m) h Q in Mm3 h Q in Mm3 h Q in Mm3 h Q in Mm3

0.1 0.0313 4.1 1.1877 8.1 2.1285 12.1 2.7836 0.2 0.0626 4.2 1.214 8.2 2.1487 12.2 2.795 0.3 0.0937 4.3 1.2402 8.3 2.1688 12.3 2.806 0.4 0.1247 4.4 1.2662 8.4 2.1888 12.4 2.8168 0.5 0.1556 4.5 1.2922 8.5 2.2086 12.5 2.8273 0.6 0.1864 4.6 1.318 8.6 2.2282

0.7 0.217 4.7 1.3436 8.7 2.2475 0.8 0.2475 4.8 1.3692 8.8 2.2668 0.9 0.2779 4.9 1.3946 8.9 2.2859 1 0.3083 5 1.4198 9 2.3047

1.1 0.3385 5.1 1.4449 9.1 2.3234 1.2 0.3686 5.2 1.4698 9.2 2.3418 1.3 0.3985 5.3 1.4947 9.3 2.3601 1.4 0.4283 5.4 1.5194 9.4 2.3782 1.5 0.4581 5.5 1.5439 9.5 2.3961 1.6 0.4876 5.6 1.5683 9.6 2.4138 1.7 0.5171 5.7 1.5925 9.7 2.4312 1.8 0.5465 5.8 1.6167 9.8 2.4486 1.9 0.5757 5.9 1.6406 9.9 2.4657 2 0.6049 6 1.6644 10 2.4825

2.1 0.6338 6.1 1.688 10.1 2.4993 2.2 0.6628 6.2 1.7116 10.2 2.5157 2.3 0.6915 6.3 1.7349 10.3 2.532 2.4 0.7202 6.4 1.7582 10.4 2.548 2.5 0.7486 6.5 1.7812 10.5 2.5638 2.6 0.7771 6.6 1.804 10.6 2.5794 2.7 0.8053 6.7 1.8268 10.7 2.5948 2.8 0.8335 6.8 1.8494 10.8 2.6099 2.9 0.8615 6.9 1.8718 10.9 2.6248 3 0.8894 7 1.8942 11 2.6394

3.1 0.9172 7.1 1.9163 11.1 2.6538 3.2 0.9448 7.2 1.9382 11.2 2.668 3.3 0.9723 7.3 1.96 11.3 2.6818 3.4 0.9996 7.4 1.9816 11.4 2.6955 3.5 1.027 7.5 2.0032 11.5 2.709 3.6 1.0541 7.6 2.0245 11.6 2.7221 3.7 1.081 7.7 2.0456 11.7 2.735 3.8 1.1079 7.8 2.0666 11.8 2.7475 3.9 1.1346 7.9 2.0874 11.9 2.7598 4 1.1612 8 2.108 12 2.7719


50


0.1 0.0308 4.1 1.1625 8.1 2.0726 12.1 2.6818 0.2 0.0615 4.2 1.1881 8.2 2.092 12.2 2.6916 0.3 0.092 4.3 1.2136 8.3 2.1112 12.3 2.701 0.4 0.1223 4.4 1.239 8.4 2.1303 12.4 2.71 0.5 0.1527 4.5 1.2642 8.5 2.1491 12.5 2.7186 0.6 0.1829 4.6 1.2894 8.6 2.1678

0.7 0.213 4.7 1.3143 8.7 2.1863 0.8 0.243 4.8 1.3391 8.8 2.2045 0.9 0.2728 4.9 1.3638 8.9 2.2227 1 0.3025 5 1.3884 9 2.2405

1.1 0.3321 5.1 1.4127 9.1 2.2582 1.2 0.3616 5.2 1.437 9.2 2.2758 1.3 0.391 5.3 1.4611 9.3 2.293 1.4 0.4202 5.4 1.485 9.4 2.3101 1.5 0.4493 5.5 1.5088 9.5 2.3271 1.6 0.4784 5.6 1.5324 9.6 2.3437 1.7 0.5072 5.7 1.556 9.7 2.3602 1.8 0.536 5.8 1.5793 9.8 2.3764 1.9 0.5646 5.9 1.6026 9.9 2.3924 2 0.5932 6 1.6256 10 2.4082

2.1 0.6215 6.1 1.6486 10.1 2.4238 2.2 0.6497 6.2 1.6713 10.2 2.4392 2.3 0.6779 6.3 1.6938 10.3 2.4543 2.4 0.7059 6.4 1.7163 10.4 2.4692 2.5 0.7339 6.5 1.7386 10.5 2.4839 2.6 0.7616 6.6 1.7607 10.6 2.4982 2.7 0.7892 6.7 1.7826 10.7 2.5124 2.8 0.8167 6.8 1.8044 10.8 2.5264 2.9 0.8442 6.9 1.8261 10.9 2.54 3 0.8714 7 1.8476 11 2.5534

3.1 0.8985 7.1 1.8689 11.1 2.5665 3.2 0.9255 7.2 1.89 11.2 2.5794 3.3 0.9523 7.3 1.911 11.3 2.5919 3.4 0.979 7.4 1.9318 11.4 2.6043 3.5 1.0057 7.5 1.9524 11.5 2.6163 3.6 1.0322 7.6 1.9729 11.6 2.628 3.7 1.0585 7.7 1.9932 11.7 2.6394 3.8 1.0847 7.8 2.0133 11.8 2.6505 3.9 1.1108 7.9 2.0332 11.9 2.6613 4 1.1367 8 2.053 12 2.6718


51

375.5 ft(114.45m) h Q in Mm3 h Q in Mm3 h Q in Mm3 h Q in Mm3

0.1 0.0302 4.1 1.1367 8.1 2.0151 12.1 2.5741 0.2 0.0603 4.2 1.1616 8.2 2.0335 12.2 2.5817 0.3 0.0902 4.3 1.1864 8.3 2.0519 12.3 2.5891 0.4 0.1201 4.4 1.2111 8.4 2.0699 12.4 2.5958 0.5 0.1498 4.5 1.2357 8.5 2.0879 12.5 2.602 0.6 0.1794 4.6 1.26 8.6 2.1055

0.7 0.2089 4.7 1.2843 8.7 2.123 0.8 0.2383 4.8 1.3084 8.8 2.1404 0.9 0.2675 4.9 1.3323 8.9 2.1574 1 0.2966 5 1.3562 9 2.1743

1.1 0.3256 5.1 1.3798 9.1 2.1909 1.2 0.3545 5.2 1.4033 9.2 2.2075 1.3 0.3832 5.3 1.4266 9.3 2.2237 1.4 0.4119 5.4 1.4499 9.4 2.2397 1.5 0.4404 5.5 1.4729 9.5 2.2556 1.6 0.4688 5.6 1.4958 9.6 2.2711 1.7 0.4971 5.7 1.5186 9.7 2.2865 1.8 0.5253 5.8 1.5411 9.8 2.3016 1.9 0.5532 5.9 1.5635 9.9 2.3165 2 0.5811 6 1.5859 10 2.3311

2.1 0.6089 6.1 1.608 10.1 2.3455 2.2 0.6365 6.2 1.6299 10.2 2.3597 2.3 0.664 6.3 1.6517 10.3 2.3736 2.4 0.6914 6.4 1.6733 10.4 2.3873 2.5 0.7187 6.5 1.6949 10.5 2.4007 2.6 0.7458 6.6 1.7162 10.6 2.4138 2.7 0.7728 6.7 1.7373 10.7 2.4267 2.8 0.7996 6.8 1.7583 10.8 2.4393 2.9 0.8264 6.9 1.7791 10.9 2.4515 3 0.8529 7 1.7998 11 2.4636

3.1 0.8794 7.1 1.8201 11.1 2.4753 3.2 0.9057 7.2 1.8404 11.2 2.4867 3.3 0.9319 7.3 1.8606 11.3 2.4978 3.4 0.958 7.4 1.8805 11.4 2.5086 3.5 0.9839 7.5 1.9003 11.5 2.519 3.6 1.0097 7.6 1.9199 11.6 2.5291 3.7 1.0354 7.7 1.9393 11.7 2.5389 3.8 1.0609 7.8 1.9585 11.8 2.5483 3.9 1.0863 7.9 1.9776 11.9 2.5573 4 1.1116 8 1.9964 12 2.5658


52


0.1 0.0296 4.1 1.1103 8.1 1.9557 12.1 2.4579 0.2 0.0591 4.2 1.1345 8.2 1.9733 12.2 2.4629 0.3 0.0885 4.3 1.1586 8.3 1.9905 12.3 2.467 0.4 0.1177 4.4 1.1825 8.4 2.0076 12.4 2.4702 0.5 0.1468 4.5 1.2063 8.5 2.0246 12.5 2.472 0.6 0.1759 4.6 1.2299 8.6 2.0412

0.7 0.2047 4.7 1.2535 8.7 2.0577 0.8 0.2335 4.8 1.2768 8.8 2.0739 0.9 0.2621 4.9 1.3001 8.9 2.0899 1 0.2907 5 1.3231 9 2.1057

1.1 0.319 5.1 1.346 9.1 2.1213 1.2 0.3472 5.2 1.3688 9.2 2.1367 1.3 0.3754 5.3 1.3913 9.3 2.1518 1.4 0.4034 5.4 1.4138 9.4 2.1667 1.5 0.4314 5.5 1.4361 9.5 2.1814 1.6 0.4591 5.6 1.4582 9.6 2.1957 1.7 0.4867 5.7 1.4801 9.7 2.2099 1.8 0.5142 5.8 1.502 9.8 2.2239 1.9 0.5417 5.9 1.5236 9.9 2.2375 2 0.5689 6 1.5451 10 2.2509

2.1 0.596 6.1 1.5664 10.1 2.264 2.2 0.623 6.2 1.5875 10.2 2.2769 2.3 0.6498 6.3 1.6085 10.3 2.2894 2.4 0.6766 6.4 1.6293 10.4 2.3018 2.5 0.7032 6.5 1.6499 10.5 2.3138 2.6 0.7297 6.6 1.6704 10.6 2.3255 2.7 0.756 6.7 1.6907 10.7 2.3369 2.8 0.7822 6.8 1.7108 10.8 2.3481 2.9 0.8083 6.9 1.7307 10.9 2.3588 3 0.8342 7 1.7505 11 2.3693

3.1 0.86 7.1 1.7701 11.1 2.3794 3.2 0.8857 7.2 1.7895 11.2 2.389 3.3 0.9111 7.3 1.8087 11.3 2.3984 3.4 0.9365 7.4 1.8278 11.4 2.4075 3.5 0.9617 7.5 1.8467 11.5 2.4161 3.6 0.9869 7.6 1.8653 11.6 2.4242 3.7 1.0118 7.7 1.8838 11.7 2.432 3.8 1.0366 7.8 1.902 11.8 2.4392 3.9 1.0613 7.9 1.9202 11.9 2.446 4 1.0859 8 1.938 12 2.4523


53

374.5 ft(114.15m) h Q in Mm3 h Q in Mm3

0.1 0.029 4.1 1.0831 0.2 0.0579 4.2 1.1067 0.3 0.0867 4.3 1.13 0.4 0.1153 4.4 1.1533 0.5 0.1438 4.5 1.1763 0.6 0.1722 4.6 1.1992 0.7 0.2004 4.7 1.2219 0.8 0.2286 4.8 1.2445 0.9 0.2566 4.9 1.267 1 0.2845 5 1.2893

1.1 0.3123 5.1 1.3114 1.2 0.3399 5.2 1.3333 1.3 0.3674 5.3 1.3551 1.4 0.3948 5.4 1.3768 1.5 0.4221 5.5 1.3983 1.6 0.4492 5.6 1.4196 1.7 0.4761 5.7 1.4407 1.8 0.503 5.8 1.4617 1.9 0.5297 5.9 1.4825 2 0.5564 6 1.5031

2.1 0.5829 6.1 1.5236 2.2 0.6092 6.2 1.5439 2.3 0.6354 6.3 1.5639 2.4 0.6615 6.4 1.5839 2.5 0.6874 6.5 1.6037 2.6 0.7132 6.6 1.6233 2.7 0.7387 6.7 1.6427 2.8 0.7643 6.8 1.6619 2.9 0.7897 6.9 1.681 3 0.8149 7 1.6998

3.1 0.84 7.1 1.7185 3.2 0.865

3.3 0.8898 3.4 0.9145 3.5 0.939 3.6 0.9634 3.7 0.9876 3.8 1.0118 3.9 1.0357 4 1.0595


54

2.2 Operation plan-

The Malampuzha dam operation plan consists of step-by-step instructions for operating the dam and reservoir during routine (normal) and emergency conditions. The operating procedures for normal operations are discussed in this chapter including operating criteria for the reservoir, spillway & outlets. The operation of a dam involves regulation of its reservoir as per project specific requirements. This includes the use of area capacity curves and design flood; both as brought outabove

Reservoir operation studies, relevant design documents, hydraulic model studiesetc.

Equipment Operating and Maintenance Instructions (Manufacturers' Instructions) Operating procedures are to be developed for both normal operations and emergency operations.

2.3 Normaloperations:

2.3.1 Instructions for operating Control Mechanisms/GateOperations:

The spillway shutters are operated as per the operation procedure stipulated after giving sufficient warnings at different reservoir levels. The service of the shutter operators is available round the clock. Every opening/adjustment will be carried out only with prior approval of the Assistant Engineer after consulting the Assistant Executive Engineer/ExecutiveEngineer.

The auxiliary power system (Diesel Generator) is available in the campus and kept ready including filling of fuel etc. In the event of power failure this auxiliary power system is operated so that the shutter operation can be resumed within notime.

The canal sluices are operated manually. These sluices are also operated as per the direction of the Assistant Engineer based on the demand and in consultation with Assistant ExecutiveEngineer.

All the spillway and outlet gates are tested on a regular basis. That is, pre monsoon inspection and post monsoon inspections are carried out jointly by the Civil and Mechanical Engineers. The reports of inspections are kept in record in a register meant for thepurpose.

The total length of spillway is 55m, which includes 4 Nos. Vertical Lift gates of size 10.97 m x 4.57 m. These shutters are fixed in hoist bridge. The operating system used for operating the shutters is winch and rope. These shutters are operated by mechanically or manually. The spill way discharge capacity at FRL is 850 m3/sec. The length of stilling basin is 26.40m and width is56.70m.

Add details / Salient features of each HM equipment ( Gate , Hoists , Trash rack etc)

indicating the details e.g size of opening , c/c of seal , c/c of wheel , overall gate size and weight , Hoist capacity , Lift of gate , Rating / size /Make of Major equipment.

2.3.1.1 Material Specification


55

2.3.1.2 Operation Of SpillwayGates Reservoir has 4 spillway gate of vertical type and lifting mechanism is chain and sprocket type .This can be operated manually or electrically. Generators are provided in case electric failure 2.3.2 Operation of theReservoir

2.3.2.1 Draft Rule Curve

A draft rule curve for FRL of 115.06m has been developed


56

2.3.3 Safetyaspects:

Instructions for safe operation of dams, state procedure for restriction of tourist to be followed, designate speed limits, maintain sanitary condition, prevent contamination, adequate warning signs, sirens,etc.

The public safety is of paramount importance at all dams and reservoirs. The general instructions in this regard are as under:

State procedures to be followed for restricting access to the dam or confining traffic

to designated areas. Indicate the procedures to be followed when tourists visit the facility.

Designate speed limits to keep the traffic within acceptable and safelimits.

Establish standards for maintaining sanitaryconditions.

Prevent contamination or pollution of water for human consumption and/or re- creationaluse.

Eliminate safety hazardsby:

- Posting warningsigns. - Removing unsafe conditions wherepossible. - Restricting public access to chutes, stilling basins, and control

rooms. - Posting safety instructions at visible and keylocations. - Maintaining warning buoys upstream of thedam. - Providing adequatesecurity.

Ensure provision of all downstream warning systems like sirens, hooters etc.

An adequate system of giving information to downstream areas regarding release of flood outflows from spillway should bethere.

At the same time instructions regarding operations, inspection and maintenance need to be strictly followed for ensuring safe operation of the dam.

The spillway gates are operated step by step after assessing the reservoir water level and inflow and as per the sequencing defined in previous paras. Evacuation will be required only in the case of large release/extreme rainfall event.

2.3.4 Flood release procedure:

Based on past experience the regulation to be maintained. – The end gates to be opened first, the difference in gate opening of any 2 consecutive bays should not exceed by more than 0.5


57

m, after opening end gate, center gate to be opened, other gates to be opened in symmetrical manner starting room center towards the end through gradual increase in the opening, while closing the gate opened last to be closed first ie reverse sequence. Complete closure of gates to be accomplished by gradual lowering by 0.2 to 0.3m in the proper sequence.

2.3.5 Reservoir capabilities:

The reservoir elevation and capacity tables for is given in 2.1.1

The reservoir elevation and spillway discharge rating tables is given in 2.1.5

2.3.6 Inflow forecasting: periodic estimates of inflow volumes for each period to be prepared, instructions and procedures for preparation of the same to be included, maps or drawings indicating location of hydrological stations where data collection on regular basis to be prepared, organizations responsible for forecasting estimates and related collection of data and conversion of forecasts in to operating plans, etc to be indicated. This is a continuous process.

Inflow into reservoirs is normally estimated by the reservoir gauging method (also called the rise and fall method or inflow-outflow method). All the outflows are added together and to it the rate of rise in storage (Positive if the level rises, and negative if it falls) is added . Expressed as an equation, this will be.

Inflow (m3/sec) = Total outflow (m3/sec) + Rate of increase in storage(m3/sec)

The rate of increase (or decrease) in storage can be determined from the observed rate of increase (or decrease) in reservoir level and the elevation capacity tables. For easy computation.

1 Example of Inflow Computation

Example.

Let the reservoir level be at 113.61-m· at 8:00AM on 13.10.18 and 113.63-m at 8:00AM on 14.10.18and total outflow be 3.7 m3/sec.

Change in level = 113.63-m-113.61-m = +0.02-m. = +2-cm

Time interval = 1 day.

Inflow =0.02x3.7x60x60/1000000=0.01333Mm3/day

2.4 Emergencyoperation:

For emergency operations, the Emergency Action Plan (EAP) should be activated when any of the emergency conditions stated under section 5.2 are observed. The EAP together with this manual shall be present on site at all times.

2.4.1 Flood Communicationsystem:


58

The widely time tested Communication to reach every corner of the flood affected zones have been radio and television and private media for the people to move to safer places by themselves in an emergency.

Communication is very Important in such occasions These days due to revolution in the telecommunication system, there is available, network of mobile phones. Advantage of this facility will be taken. Mobile numbers of all such staff will be listed and made available to all the personnel who have been assigned duty of disaster management.

Apart from that, for ensuring smooth flood monitoring interstate co-ordination meeting is conducted yearly in Mumbai Maharashtra state before onset of monsoon on 25th May.

Following liaising officers for flood co-ordination of Malampuzha Dam are as listed below

Kerala State:

Table 2.4 Liaising officers for flood co-ordination of Malampuzha Dam

Authority Name, Title, Phone/Email

Dam Operator/Site

officials

Title : Assistant Engineer

Office Ph:

Email:[email protected]

Title :Assistant Executive Engineer,

Headworks Sub division, Malampuzha.

Office Ph: 0491 2815100


Emergency

Planning Manager

Title : Executive Engineer,

Irrigation Sub Division,Malampuzha

Office Ph: 04912815331


Kerala Water Resources Department

Title : Chief Engineer, Projects I, Kozhikode Office Ph: 04952385595 Email: –[email protected]

Title : Superintending Engineer, Siruvani ProjectCircle,Palakkad Office Ph: 04912577425 Email:[email protected]


59

Kerala Dam Safety Organisation

Title : Chief Engineer, IDRB, Tvpm Office Ph: 0471-2306159, 0471- 2784001 Email:[email protected]

Title: Director (Designs), IDRB, Tvm. Office Ph: 0471-2303972 Email:[email protected]

District Administration- Palakkad

Title: District Collector, Civil Station, Palakkad Office Ph: 0491-2505266

[email protected]

2.5 Drawdown facility:

All water releases facilities including outlet works, sluices, gated spillways, etc should be available for evacuation to the extent that their reliability in an emergency situation can be reasonably certain.

Reservoir level may be required to be lowered if a critical/emergency condition occurs or for carrying out repairs to the dam on its upstream slope/face in dry condition. For general guidance the ACER Technical Memorandum no. 3 - Criteria and Guideline for evacuating storage reservoirs and sizing low level outlet works & IS: 15472 – Guidelines for planning of low level outlets for evacuating storage reservoirs may be referred to. Care is to be taken to restrict the reservoir draw down rates to prevent failure of upstream slope of the Embankment/ land- slides along reservoir periphery etc. The actual drawdown rates both under normal and emergency conditions have to be decided by the DamDesigners.

2.6 Initial filling ofreservoir:

The prime consideration in deciding the rise of water should be to allow the dam to adjust to the forces it will experience as the water level behind it increases. Reservoir filling is governed by IS: 15472 – guidelines for planning and design of low level outlets for evacuating storage reservoirs in which guidelines regarding initial filling of reservoirs have beendescribed.

2.7 Recordkeeping:

Keep accurate records of the following items pertaining to projectoperation:-

Rainfall and Reservoir Levels – On daily basis during non-monsoon and on

hourly basis duringmonsoon.

Release through outlet/sluices on daily basis for irrigation, water supply, hydropower etc.


60

Outflows through spillway during monsoon on hourly basis and during non-monsoon on dailybasis.

Records of drawdown with reservoir levels, quantity of water released, drawdown rates, reason fordrawdown

Water Audit register to be maintained on daily basis by accounting all the re-leases, incremental storage in the reservoir,etc.

Security protocols to be in place along with operatingprotocols.

Visitors register with complete details like name, address, designation, purposeetc.

Other Procedures – Maintain a complete record of all operatingprocedures


61

Chapter3. PROJECTINSPECTION

The current practice of Inspection at Malampuzha dam envisages the Division Officers to carryout pre-monsoon and post-monsoon inspections. The checklist proforma included in this chapter is currently in use at Malampuzha dam.

Detailed description on project inspections is available in the Guideline for Safety Inspection of dams (Doc No. CDSO_GUD_DS_07_ v1.0), CWC2018 (https://damsafety.in/ecmincludes/PDFs/Guidelines_for_Safety_Inspection_of_Dams.pdf).

However an overview of the various types of inspections to be carried out at Malampuzha dam is given below. Note that for uploading Inspection Data into DHARMA, the Inspection Instructions & Forms given in the aforementioned Guideline for Safety Inspection of Dams must be used (see Appendix 3)). An effective inspection program is essential to identifyproblems and to keep Malampuzha Dam in a good and healthy condition This Chapter provides guidance on carrying out other inspections.

3.1 Types of inspections

An overview of inspections, whose frequency would be based on the hazard classification, condition of dam, CDSO regulations, etc. are given below,-

InformalInspections,

Scheduled Inspections (pre and post monsoon &others), SpecialInspections,

Comprehensive EvaluationInspections

3.2 Informalinspections

These are the first line of defense and performed by personals posted to dam sites. Any defects noted must be reported to authorities concerned.

An informal inspection, is a continuing effort by onsite personnel (dam owners/operators and maintenance personnel) performed during their routine duties. Informal inspections are critical to the proper operation and maintenance of the dam. They consist of frequent observations of the general appearance and functioning of the dam and appurtenant structures.

Operators, maintenance crews, or other staffs who are posted at dam site are conducting formal inspections. These people are the “first-line of defense” in assuring safe dam conditions, and it is their responsibility to be familiar with all aspects of the dam. Their vigilance in walking across the dam, checking the operating equipment, and noting changes in conditions may prevent serious mishaps or even damfailures.

Informal inspections are important and are performed at every available opportunity. These inspections may only cover one or two dam components as the occasion presents itself, or they may cover the entire dam and its appurtenant structures. The informal inspections are not as detailed as comprehensive evaluation, scheduled, and special inspections and will only


62

require that a formal report is submitted to the dam owner’s project files if a condition is detected that might endanger the dam. Report is to be submitted covering details of the condition of various dam components observed at site along with photographs, time & date of visit, reservoir water level and other important aspectsetc.

3.3 Scheduledinspections

Scheduled inspections shall consist of Pre- monsoon and Post-monsoon and any other inspections carried out by State Dam Safety Organization/ any expert panels constituted by dam owners and the information is used to establish needed repairs.

These inspections are performed to gather information on the current condition of the dam and its appurtenant works. This information is then used to establish needed repairs and repair schedules, and to assess the safety and operational adequacy of the dam. Scheduled inspections are also performed to evaluate previous repairs. The purpose of scheduled inspectionsistokeepthedamanditsappurtenantstructuresingoodoperatingconditionand to maintain a safe structure. As such, these inspections and timely maintenance will minimize long-term costs and will extend the life of the dam. Scheduled inspections are performed more frequently than comprehensive evaluation inspections to detect at an early stage any developments that may be detrimental to the dam. These inspections involve assessing operational capability as well as structural stability and detection of any problems and to correct them before the conditions worsen. The field examinations should be made by the personnel assigned responsibility for monitoring the safety of the dam. If the dam or appurtenant works have instrumentation, the individual responsible for monitoring should analyze measurements as they are received and include an evaluation of that data. Dam Inspection Report or an inspection brief should be prepared following the field visit (Dam Inspection Report isrecommended).

Scheduled inspections include the following four components as a minimum:

File review of past inspection reports, monitoring data, photographs, maintenance records, or other pertinent data as may berequired;

Visual inspection of the dam and its appurtenantworks;

Preparation of a report or inspection brief, with relevant documentation and photographs. The report should be filed in the dam owner’s project files

Education and training if someone other than the owner is performing theinspection

3.3.1 Pre- and Post-Monsoon Checklist and Example of Report Performa Detailed checklists are required to ensure the health of the dam and to ensure that it continues to operate in satisfactory and safe condition. The Performa to be used for inspection should be the one enclosed in the Doc No. CDSO_GUD_DS_07_ v1.0, CWC 2018 on the Guidelines for Safety Inspection of Dams.

3.4 Special (unscheduledinspection)

Special inspections may need to be performed to resolve specific concerns or conditions at the site on an unscheduled basis. Special inspections are not regularly scheduled activities,


63

but are usually made before or immediately after the dam or appurtenant works have been subjected to unusual events or conditions, such as an unusually high flood or a significant earthquake. These inspections are to be carried out after an initial assessment based on informal inspection carried out by project personnel reveal dam safety related concerns like cracking in the dam, damages, erosion/ scour, undermining/ piping/ sink holes/ liquefaction or any such undesirable feature. A special inspection may also be performed during an emergency, such as an impending dam breach, to evaluate specific areas or concerns. They are also made when the ongoing surveillance program identifies a condition or a trend that appears to warrant a special evaluation. Special inspections should focus on those dam components that are affected by the unusual event and should include at least threeelements:

1) Review of available relevant files ordata,

2) Visual inspection of all components of the project and surroundings,and

3) Report preparation covering status of project andrecommendations.

More detailed site investigations / studies may be required (such as drilling, surveys, or seepage flow estimates) if the special inspection reveals the need for the same. Photographic documentation is to be included as part of the inspection.

3.5 Comprehensive evaluationinspections

3.5.1 General

For comprehensive dam safety evaluation for each dam an independent panel of experts known as Dam Safety Review Panel (DSRP) needs to be constituted for determining the condition of the dam and appurtenant works. The panel will undertake evaluation of the dam once in 10 years or on occurrence of any extreme hydrological or seismic event or any unusual condition of the dam or in the reservoir rim. The terms of reference of the comprehensive dam safety evaluation shall include but not be limited to;

1. General assessment of hydrologic and hydraulic conditions, review of design flood, flood routing for revised design flood and mitigationmeasures.

2. Review and analysis of available data of dam design including seismic safety, construction, operation maintenance and performance of dam structure and appurtenant works.

3. Evaluation of procedures for operation, maintenance and inspection of dam and to suggest improvements /modifications.

4. Evaluation of any possible hazardous threat to the dam structure such as dam abutment slope stability failure or slope failures along the reservoirperiphery.

3.5.2 Details to be provided to DSRP beforeinspection


64

All relevant details/data/drawings for the dam project to be inspected by the Panel of Experts

shall be provided at least 4 months in advance of the proposed visit. This will include:-

(a) GeneralInformation

1. Scope ofproject

2. Basic data and salient features

3.Issues related to safety of dam

4.Details of keypersonnel

5.Emergency preparedness – Communications, Auxiliary Power, Downstream Warning system & Security of site.

(b) Hydrology

1. Description of drainage basin

2. Original inflow designflood

3. Spillway capacity at FRL & original MWL

4.Surface area & storage capacity of the reservoir

5.Flood routing criteria &results

(c) Geology

1. Dam site geology including geological reports

2.Quality and sufficiency of the geological investigations.

3.Special problems and theirtreatment

4.Reservoir competency as per geological report.

5.Slope stability issues along reservoir rim.

(d) Layout including Drawings

1.Dam

2. Spillway

3. Junction between Embankment & Concrete dams

4.River/Canaloutlets

5.Instrumentation

(e) Dam and Spillway


65

1. Geology

2.Specialproblems

3. Foundation treatment including treatment of faults/shear zones/ weak zones, curtain/consolidation grouting, drainage provisions, any other special treatment, cutoff trench, diaphragm wallsetc.

4. Design criteria and result of stabilityanalysis

5. Special studies (Finite element/Dynamic Analysisetc.)

6. Adequacy of design – from dam safetyconsiderations

7. Hydraulic design of Spillway and Energy Dissipation Arrangements including past model studyreports.

8. Instrumentation – analysis and interpretation of instrumentation data including structural behaviorreports. 9. Pre-construction material testing reports including adequacy of field and laboratory investigations, appropriateness of materials selectedetc.

10. Post-construction testing reports, ifany.

11. Seismicity (Seismic Parameters approved by the National Committee for Recommending Seismic Design Parameters forDams)

f) Construction history

g) Dam incidents/failures, remedial measures/modificationsundertaken

h) Reservoir Operation & Regulation Plan

1.General

2. Reservoir filling

3. Water releases – normal and duringfloods.

3.5.3 Field Inspection – Observation & Recommendations regarding RemedialMeasures

Each component of the project is to be inspected; evaluated and specific problems are to be brought out. Recommendations for necessary remedial measures need to be included in the panel s report. Various project components to be inspected shall include but will not be limitedto;

(a) Dam

1. Upstreamface


66

2. Downstreamface

3. Top of dam

4. Structural behavior as observed visually and as per evaluation of

Instrumentation data (any visible cracking, deflections etc.)

5.Seepageassessment

6. Condition of natural/excavated slopes in the abutments, both on u/s and d/s

of thedam.

7. Any specificproblems/deficiencies

(b) Spillway

1. Civil structure

2. Energy Dissipation Arrangements (EDA)

3.Spill channel, drop structures etc. ifany.

4.Condition of EDA and its performance

5.Spillway Gates & Hoists

6.Downstream safe carrying capacity of river / channel.

(c) River / Canal Outlets

1.Civilstructures

2. Outlet Gates, Hoists &Controls

3. Conducts / Outlets through Embankment dams and sluices through Concrete dams (Condition, problemsetc.)

4. Trash racks, if any

5. Separate energy dissipation arrangements, if any.

(d)Review of Sedimentation of theReservoir.

1.Assessment of sedimentation and its effect on flood routing, operation/ life of

reservoir.

(e) Flood Hydrology

1. Extent& sufficiency of data available,

2.Method used for estimating the design flood.


67

3.Design flood reviewstudy.

4.Flood routing studies with the revised flood

5.Adequacy of free board available

(f) Miscellaneous services /facilities

1.Access Roads / Bridges / Culverts

2.Stand by power arrangements

3.Flood forecastingarrangements

4.Communication facilities (Telephone, Satellite, Wireless, Mobile, etc.)

(g) Hydraulic Model studies, if any new studies carriedout.

(h) Earlier reports of experts / DSRP etc., if any, asannexure.

(i) Photographs of dam project showing problemareas.

3.5.4 ComponentsInvolved

A comprehensive evaluation inspection of a dam will consist of five components:

1. Project records review (i.e. study of all design / construction records/drawings, history of the dam’s performance, past inspection notes/reports, notes on distress observed/ any rehabilitation measures undertaken earlieretc.).

2. Inspection of the dam and its appurtenantworks. 3. .Review results/ reports of additional field investigations & laboratory testing as

required. 4. Review of design studies e.g. review of design flood, checking of the adequacy of

spillway capacity, freeboard requirements, dam stability, any special study as required.

5. Preparation of a detailed report of theinspection


68

Chapter 4. PROJECT MAINTENANCE

A good maintenance program protects Malampuzha Dam against accelerating deterioration, prolongs its life, and greatly reduces the chance of failure. Nearly all the components of Malampuzha Dam and its materials are susceptible to damage and deterioration if not well maintained. Moreover, the cost of a proper maintenance program is small compared to the costs of major repairs, loss of life and property and litigation. Preventative maintenance not only protects the dam and its owner but the public as well. If maintenance of a dam is neglected the consequences and costs will multiply.

4.1 Maintenance plan:

Preventive maintenance assures that a dam and reservoir are in good working condition and prevents more harmful conditions from developing. Individual maintenance tasks are noted, with a description of the area where the maintenance is to be performed, the schedule for performing the tasks, and reporting procedures. Typical routine maintenance tasks performed includes mowing grass, removing vegetation, bushes and trees, removing litter and other debris, re-grading the crest and/or access roads, repairing fencing to keep livestock off the dam, etc. Other maintenance works that need to be performed on the embankment includes restoration of embankment to its design section, seepage problems, erosion, displaced riprap, cracking in embankment etc. In concrete / masonry dams there may be issues like cracking and disintegration in concrete, choking of Porous/formed drains in dam bodyand drainage holes in the foundation gallery, damages to spillway glacis/piers/energy dissipation arrangement due to abrasion/ cavitations/unsymmetrical flows, damages to pointing on upstream & downstream faces of masonry dams, heavy seepages through some drains in foundation/inspection galleries etc.

A basic maintenance program has been developed primarily based on systematic and frequent inspections.

4.2 Maintenance priorities:

In order of priority needs to be clarified under the heads of maintenance

4.2.1 Immediate maintenance–

The following conditions are critical and call for immediate attention & reservoir lowering, if warranted. These conditions may include, but are not limited to:

The dam is about to be overtopped or being overtopped during highflood.

The dam is about to be breached by erosion, slope failureetc

The dam showing signs of piping or internal erosion indicated by increasingly cloudy seepage or othersymptoms.

The spillway being blocked or with some inoperablegates.

Evidence of excessive seepage appearing anywhere on the dam site ,e.g., the Embankment becomes saturated, defective water stops, etc., and seepage exiting on the downstream face is increasing involume.


69

Although the remedy for some critical problems may be obvious (such as clearing a blocked spillway or repairing the spillway gates so that they are in working condition), the problems listed above generally demand the services of experienced engineers/expert panels familiar with them design, construction and maintenance of dams. The emergency action plan (EAP) should be activated when any of the above conditions are noted.

4.2.2 Preventivemaintenance

This can be further classified as Condition based Maintenance and Routine Maintenance.

4.2.2.1 Condition based maintenance – To include the following but not limitedto

● Remove all vegetation and bushes by roots from the dam and restoring any eroded areas and to establish a good grasscover.

● Fill animalburrows

● Repair livestock trails and fences to keep livestock offdam. ● Restore and reseed eroded areas and gullies on embankmentdams. ● Repair of defective gates, valves, and other hydro-mechanicalequipment. ● epair any concrete or metal components that havedeteriorated. ● Cleaning of the choked porous drains in the dam body and drainage holes in the

foundation gallery in concrete/masonrydams. ● Repair any damages on spillway glacis, piers, energy dissipaters, training/divide

walls, downstream areas etc. ● Repairs on the upstream face of masonry dams, in case the pointing is damaged, due

to which there is increasedseepage. ● Controlling any heavy seepage inthe foundation/inspection galleries in Concrete/Masonry dams

from drainage holes.

● Repairs of any cracks/cavities/joints in concrete/masonry dams/structures.

However many of these works will require the services of experienced engineers/expert

panels.

4.2.2.2 Routine maintenance - To include the following but not limitedto

● Routine mowing, restore and reseed eroded areas and gullies on downstream face

of embankment dams and general maintenance including repairs/ cleaning of surface drains on downstream face & in the downstreamareas.

● Maintenance and treatment of any cracks/joints/cavities in Concrete/Masonry dams and spillways based on the recommendations of experienced engineers/expertpanels.

● Observation of any springs or seepage areas, comparing quantity and quality (clarity) with reference to earlier observations in embankment dams.

● Monitoring of development in the upstream watershed which would materially increase runoff and sediment fromstorms.

● Monitoring of downstream development which could have an impact on the dam and its hazardcategory.


70

● Maintenance of Electrical & Hydro- Mechanical equipment and systems e. g. Servicing of spillway gates & stop logs, hoisting arrangements, gantry crane, gates/hoist of outlet works/ sluices & stand bygenerator.

● Proper lighting at dam top, galleries in damsetc. ● Monitoring of seepage in galleries of concrete/masonrydams. ● Monitoring/cleaning & removal of leached deposits in porous / formed drains in

dam body & drainage holes of Concrete/ Masonry dams in foundationgallery. ● Maintenance of all dam roads & accessroads.

● Operation of electrical and mechanical equipment and systems including

exercising gates &valves. ● To keep the gate slots clear ofsilt/debris. ● Maintenance/testing of monitoring equipment (instruments) and safetyalarms. ● Testing of securityequipment. ● Testing of communicationequipment. ● Any other maintenance considerednecessary.

4.3 Maintenance items-

The O&M Manual includes detailed instructions and schedules for performing periodic maintenance works at the site. This include maintenance of the dam, the appurtenant works, and the reservoir areas. Methodology / Specifications for carrying out maintenance works of general & recurring nature should be included in the Manual. Dam repairs are scheduled based on severity of the problem, available resources, and weather conditions. For example, if a severe settlement problem (more than envisaged in designs) or cracking is detected on the crest of the dam, it should have a high priority since further degradation could lead to dam breaching. The causes of all major issues / problems should be identified and evaluated by experienced engineers/ Expert Panels so that appropriate remedial measures can be finalized. Correcting minor rill erosion on the downstream slope could be assigned a low priority since it is not a dam safety concern. This type of repair will also be weather dependent, since grass can only be planted during specific times of the year, and the embankment should be dry so that more damage is not inflicted to the embankmentslopes.

4.3.1 Earthwork–

The surfaces of an earthen dam may deteriorate due to several reasons. For example, wave action may cut into the upstream slope, vehicles may cause ruts in the crest or slopes, trails left by livestock can result in erosion, or runoff waters may leave erosion gullies on the downstream slope. Other special problems, such as shrinkage cracks or rodent damage, may also occur. Damage of this nature must be repaired constantly.

The maintenance procedures described here are effective in repairing minor earthwork problems. However, this section is not intended to be a technical guide, and the methods discussed should not be used to solve serious problems. Conditions such as embankment slides, structural cracking, and sinkholes threaten the immediate safety of a dam and require immediate repair under the directions of experienced engineers/Expert panels.


71

The material selected for repairing embankments should be free from vegetation, organic materials, trash, and large rocks.

If flow-resistant portions of an embankment are being repaired, materials that are high in clay or silt content should be used. If the area is to be free draining or highly permeable (such as pervious shell of an embankment dam) the material should have a higher percentage of sand and gravel. It is usually satisfactory to replace or repair damaged areas with soils like those originally in place. An important soil property affecting compaction is moisture content. Soils that are too dry or

too wet do not compact well. One may test repair material by squeezing it into a tight ball. If the sample keeps its shape without cracking and falling apart (which means it is too dry), and without depositing excess water onto the hand (which means it is too wet), the moisture content is near the proper level.

Before placement of earth, the repair area needs to be prepared by removing all inappropriate material. All vegetation, such as bushes, roots, and tree stumps, along with any large rocks or trash need to be removed. Also, unsuitable earth, such as organic or loose soils, should be removed, so that the work surface consists of exposed, firm, clean embankment material.

Following cleanup, shape and dress the affected area so that the new fill can be compacted to the level specified in the technical specifications. Also it should properly key with the existing fill. Further trim the slopes and roughen the surfaces by scarifying or plowing to improve the bond between the new and existing fill and to provide a good base to compact against.

Place soils in loose layers up to 20 centimeters thick and compact manually or mechanically to form a dense mass free from large rock or organic material. Keep soil moisture in the proper range. The fill should be watered and mixed to the proper wetness and allowed to dry if too wet.

Erosion is one of the most common maintenance problems at embankment structures. Erosion is a natural process and its continuous forces will eventually wear down almost any surface or structure. Periodic and prompt maintenance is essential to prevent continuous deterioration and possiblefailure.

Turfing, free from weeds and bushes, is an effective means of preventing erosion.

Rills and gullies should be filled with suitable soil, compacted, and then seeded for growing the turfing. Erosion in large gullies can be slowed by stacking bales of hay or straw across the gully until permanent repairs can be made.

Paths due to pedestrian, livestock, or vehicular traffic (two and four-wheeled) are a problem on many embankments. If a path has become established, vegetation will not provide


72

adequate protection and more durable cover will be required unless traffic is eliminated. Stones may be used effectively to cover suchfootpaths.

In addition, steps can be provided/ constructed at regular intervals along the length of the dam for going from downstream toe to the dam top. All vehicular traffic, except for maintenance, should be restricted from thedam.

Erosion is also common at the point where an embankment and the concrete walls of a

spillway or other structure meet. Poor compaction adjacent to such walls during construction and later settlement can result in an area along the wall that is lower than the grade of the embankment.

Runoff, therefore, often concentrates along these structures, resulting in erosion. People also often walk along these walls, wearing down the vegetative cover. Workable solution include re-grading the area so that it slopes away from the wall, adding more resistant surface protection, or constructing steps.

4.3.2 Upstream riprap- The upstream face is protected against wave erosion. Rip-rap is provided for the purpose with filter layers below.

Nonetheless, erosion can still occur in existing riprap. Water running down the slope under the riprap can erode the finer filter materials under the riprap and soils leaving voids and loss of grade. Wave run up will also undermine the filter layer especially along the full reservoir level and over time wash out finer material. This can be checked through observance of linear embankment settlement. Sections of riprap that have slumped downward are often signs of this kind of erosion.

When erosion occurs on the upstream slope of a dam, repairs should be made as soon as possible. (Refer IS: 8237- Code of practice for protection of Slopes for Reservoir Embankments)..


73

Fig 4.1 Upstream rip rap

4.3.3 Controlling vegetation – Keep the entire dam clear of unwanted vegetation such as bushes or trees. Excessive growth may cause several problems:

It can obscure the surface of an embankment and not allow proper inspection of the dam.

Large trees can be uprooted by high wind or erosion and leave large voids that can lead to breaching of thedam.

Some root systems can decay and rot, creating passageways for water, leading to pipingerosion.

Growing root systems can lift concrete slabs orstructures. Rodent habitats can developundetected.

All bushes/trees should be as far as possible removed by roots. The resulting holes should be

filled with well compacted earth. It would be desirable to remove the plants/vegetation at their early stage to prevent their growing into big tree/bushes. In cases where trees and bushes cannot be removed, the root systems should be treated with herbicide (properly selected and applied) to retard further growth. Concerned Government Agencies should be consulted for selection of appropriate herbicides & their use for control of vegetation on damstructures.

Further, it is desirable that there are no trees or bushes within 500 m of the toe drain on the downstream side of the dam.

4.3.4 Controlling animal damage– Livestock should not be allowed to graze on an embankment surface. Livestock are not

allowed to graze on the embankment section of the dam. When soil is wet, livestock can damage vegetation and disrupt the uniformity of the surface. Moreover, livestock tend to


74

walk in established paths and thus can promote erosion. Such paths should be re-graded and seeded, and the livestock permanently fenced out of thearea.

The burrows and tunnels of burrowing animals (beaver, muskrat, groundhogs and others) should be filled by mud packing. The method involves placing vent pipe in a vertical position over the entrance of the den. Making sure that the pipe connection to the den does not leak, the mud-pack mixture is poured into the pipe until the burrow and pipe are filled with the soil-water mixture. The pipe is removed and more dry earth is tamped into the entrance. The mud pack is generally made by adding water to 90% earth & 10% cement mixture until a slurry or thin cement consistency is attained. For bigger holes, bentonite coated stones can also be used. All entrances should be plugged with well compacted earth & vegetation re- established. Dens should be eliminated without delay. Different repair measures are necessary if a dam has been damaged by extensive small rodent tunneling or large rodent activity. Excavate the area around the entrance and then backfill it with impervious material. This plugs the passage entrance so that water is prevented from saturating the dam‘sinterior.

4.3.5 Controlling ants and termites (white ants)– Ants and termites if left undisturbed can build mounds that can become quite large. Frequent mowing can induce the colonies to migrate to neighboring, undisturbed areas. Use only pesticides labeled as suitable for the location you want to treat. Make every effort to avoid contaminating water with pesticide.

4.3.6 Controlling damage from vehicular traffic– Vehicles, except for maintenance, should be restricted on the dam top and kept out by fences or barricades. Any ruts should be repaired as soon as possible. In the case of existing dams having permission for movement of nearby villagers, heavy traffic movement may beavoided. If possible, separate connectivity may be explored for such cases. In the case of barrages and dams having provisions for roads of National/State Highways etc., all efforts should be made to restrict the speed of vehicles. Regular maintenance of bridges and roads shall be mandatory.

4.3.7 Masonry/ concrete dams and spillways– Various issues/problems that may need maintenance /repairs in Concrete/Masonry dams& Spillways may include but are not limited to:

● Cracking in concrete (potential causes are alkali – aggregate reaction, thermal stresses because of heat of hydration or temperature variations, foundationproblems).

● Damages on spillway glacis, spillway piers, training/divide walls, energy dissipaters, downstream areas (probable causes are cavitations, abrasion, unsymmetrical flows, unfavorable downstreamconditions)

● Vegetation growth in unattended Auxiliary spillways, spill channel, approach channel etc.

● Seepage in Galleries and on d/s face of thedam. ● Cleaning and removal of leached deposits from choked drainage holes in the dam


75

body/foundations. ● Repair to upstream face of masonry dams in case the pointing is damaged, leading to

increasedseepage. ● To ensure proper access & lighting ingalleries. ● To ensure that the dam is behaving as designed based on instrumentationprograms. ● Periodic maintenance should be performed of all concrete surfaces to repair

deteriorated areas. Repair deteriorated concrete at the earliest; it is most easily repaired in its initial stages. Deterioration can accelerate and, if left unattended, can result in serious problems or dam failure. (For remedial measures of problems of special nature advice of experienced engineers/ Panel of Experts needs to beobtained)

4.3.8 Outlet works– Outlet conduits should be inspected thoroughly once a year. Circular conduits that are one and a half meter or more in diameter can be entered and visually inspected. Common problems are improper alignment (sagging), separation and displacement at joints, cracks, leaks, surface wear, loss of protective coatings, corrosion, and blockage. Problems with conduits occur most often at the joints. Further collars at joints used to also lead to inadequate compaction. Hence, special attention should be given to them during the inspection. The joints should be checked for gaps caused by elongation or settlement and loss of joint-filler material. Open joints can permit erosion of embankment material or cause leakage of water into the embankment during pressure flow. The outlet should be checked for signs of water seeping along the exterior surface of the pipe. A depression in the soil surface over the pipe may be a sign that soil is being removed from around thepipe.

Listed below are common concerns regarding repairs to outlet works:

● Asphalt mastic isnot recommended for other than temporary repairs. Asphalt mastic used as joint filler becomes hard and brittle, is easily eroded, and as per literature survey it may provide a satisfactory seal for only about five years. Mastic should not be used if the conduit is expected to flow underpressure.

● The instructions on the label should be followed when using thermosetting plastics (epoxy). Most of these products must be applied to a clean and dry surface to set up an effective bond. However cementations materials are to be preferred in view of their UV resistance & longerlife.

● Material used as joint filler should be impervious to water and should be flexible throughout the range of expected air and watertemperatures.

● The internal surfaces of the conduit should be made as smooth as possible when repairs are made so that high-velocity flow will not damage the repairmaterial.

● Minor cracks in concrete are not considered a dangerous problem. Repair is not necessary unless the cracks widen orleak.

The general practice now is not to go in for pre-cast concrete/MS pipe conduits with collars but to construct RCC conduits at site without any collars and joints. PVC water stops are provided at joints and the exterior collars but to construct RCC conduits at site without any collars and joints. PVC water stops are provided at joints and the exterior faces of the


76

conduits are given a slope to enable better contact at the interface withearth.

4.3.9 Trash racks – Trash racks at intakes that have become clogged with debris or trash reduce their discharging capacity. The head losses through clogged trash racks also increase or reduce their discharging capacity. The head losses through clogged trash racks alsoincrease.

Maintenance of trash racks includes periodic inspections for rusted and broken sections and repairs are made as needed. Trash racks should be checked during and after floods to ensure that they are functioning properly and to remove accumulated debris.

4.3.10 Gates & hoisting equipment– The safe and satisfactory operation of a dam If routine inspection of the Hydro- Mechanical Equipment shows the need for maintenance, the work should be completed as soon as possible. The simplest procedure to ensure smooth operation of gates is to operate them through their full range at least once, and preferably twice annually (before monsoon & after monsoon keeping a gap of at least six months). Because operating gates under full reservoir pressure can result in large discharges, exercising of gates should preferably be carried out in dry conditions using stop-logs/ emergency gates. Commonly used Gates and Hoists including their inspection / maintenance requirements are discussed below. The O&M manuals of the gates manufacturer‘s would however govern the overall maintenance of Gates & Hoists whenever there is any contradiction with the instructions given in the Manual.

4.3.10.1 Vertical lift fixed wheel and slide gates– These gates are provided in spillways, outlet works, sluices etc. for controlling/regulating the flow. The main components of these gates are as under;


77

Fig 4.2 Vertical gate

i). Embeddedparts: • Sill beamassembly • Top and side sealseats • Rollertrack • Sideguide • Doggingarrangement

ii). GateParts: • Skin plateAssembly • EndVerticals • Horizontalgirders • VerticalStiffeners • Rollerassembly • Seal Assembly • Side guideassembly • LiftingArrangement

The aspects to be inspected and maintained periodically for ensuring proper operation of these gates are as under;

i) The gate slot and bottom platform/ sill beam should be cleaned periodically. Scales formed over the embedded parts should be removed. Second stage concrete should be checked for any development of cracks/leakages and repairs should be attended toimmediately. ii) The gate leaf should be thoroughly cleaned and repainted as and when necessary according to the procedure or guidelines- indicated in IS: 14177 or as per the recommendations of the paint manufacturer. All drain holes provided in the gate assembly should becleaned. iii) Rubber seals should be smoothened, if required, for proper alignment. All nuts and bolts


78

fixing the seal to the gate should be tightened uniformly. Seals, if found damaged or found leaking excessively should be adjusted, repaired or replaced as considerednecessary. iv) The wheel shall be rotated to check their free movement. Gate roller bearings and guide roller bushes should be properly lubricated. Whenever necessary these should be opened for rectifications of defects, cleaning and lubrication and should thereafter be refitted. These may be replaced if repairs are notpossible. v) Hoisting connection of the gate leaf should be lubricated where necessary and defects if any should berectified. vi) All nuts, bolts, check nuts and cotter pins of the lifting devices should be checked periodically. vii) All components should be greased and lubricated. Recommended and approved oils and grease only should beused. viii) Roller assembly should be adjusted by the eccentricity arrangement to ensure all rollers rest uniformly on the track plates particularly in the closed position of thegate. ix) Where filling valves are provided as part of the gate structure, all the nuts, bolts, check nuts etc. should betightened. x) All welds shall be checked for cracks/damages. Any weld that might havebecome defective should be chipped out and redone following the relevant codal provisions. Damaged nuts, bolts, rivets, screws etc. should be replaced withoutdelay. xi) The filling-in valves allow passage of water when it is lifted by lifting beam & crane due to creation of space between stem seat and exit passage liner. The springs and associated components should be checked periodically for damages and replaced ifnecessary. xii) The guide-assemblies, wheel assemblies and sealing-assemblies shall be cleared off grit, sand or any other foreignmaterial. xiii) The wheel pin shall be coated with corrosion resistantcompound. xiv) All nuts and bolts shall betightened.

4.3.10.2 Electrically operated fixedhoists a) GeneralInstructions

● Operation of fixed hoist without lifting the gate is not possible and need not therefore be attempted. It will be possible to operate the unit and observe operation of load carrying hoist component when gate is being lifted orlowered.

● Never open any bolt or nut on motor, gear boxes, rope drums and other load carrying hoist components when the gate is in raised position. The gate should be fully closed or rested on the gate latches before carrying out any work on hoist components including motor brake and other electricalequipment.

b) Inspection andMaintenance The aspects to be inspected and maintained periodically for ensuring proper operation of Rope drum hoists are as under;

● Entrance to all hoist platforms shall be kept locked. All keys shall remain with the shift supervisor.

● A cursory daily inspection shall be made of hoist and gate to ensure that there is no unusualhappening.


79

● Clean all hoisting equipment and hoistplatform. ● Check oil level in gearboxes and replenish as and when required with oil of proper

grade. ● Apply grease of suitable grade by greasegun. ● Lubricate all bearings, bushings, pins, linkagesetc. ● Check all the fuses on the powerlines. ● All bolts and nuts on gear boxes, hoist drum and shaft couplings should be checked

fortightness. ● Check the supplyvoltage. ● Drain sample gear oil from each of the gear boxes. If excessive foreign particles or

sludge is found, the gear box shall be drained, flushed and filled with newoil. ● All the geared couplings shall begreased. ● Raise and lower the gate by hoist motor and check for smooth, and trouble free

operation of gate without excessivevibration. ● Observe current drawn by motor at the time of lifting and check if it is more than

normal. If so, stop the hoist and investigate the cause andrectify. ● Check the condition of painting of various components and remove rust wherever

noticed and repaint the portion after proper cleaning as per paintingschedule. ● All trash, sediments and any other foreign material shall be cleared off the lifting rope

and liftingattachment. ● All ropes shall be checked for wear and tear and if broken wires are noticed, the rope

shall bereplaced. ● All the wire ropes shall be checked and all visible oxidation shall beremoved. ● All wire ropes shall be greased with cardiumcompound. ● Check the overload relays for properfunctioning. ● Check all the nuts, bolts, rivets, welds and structural components for hoisting platform

and its supporting structure for wear, tear and damage. All damages shall be rectified. All bolts shall be tightened. The portion with damaged painting shall be touchedup.

● Check the pulleys, sheaves andturnbuckles. ● Raise and lower the gate for its full lift several time (at least three to four) and observe

thefollowing: Check the limit switches and adjust for design limits. - The effectiveness and slip of the breaks shall be checked by stopping the gate in raising and lowering operations. The brakes shall be adjusted if needed. - When the gate is operated, there should not be any noise or chatter in the gears.

● Adjust the rope tension of wires ifunequal. ● Check for all gears and pinions for uneven wear and adjust for proper contact. Grease

thegears. ● Repaint the hoist components, hoisting platform and its supporting structures as per

requirement. ● The periodic maintenance of commercial equipment like motors, brakes, thrusts etc.

shall be carried out as per manufacturers operation and maintenancemanual.

4.3.10.2.1 Maintenance of Electrical components of fixed rope drum hoists – The electrical components to be inspected and maintained periodically are asunder;


80

i) Starters should be cleaned free of moisture anddust. ii) Each individual contactor should be tried by hand to make sure that it operatesfreely. iii) All wearing parts should be examined in order to take note of any wear which may have occurred duringoperation. iv) If the contactor hums, the contact faces should becleaned. v) Examine all connections to see that no wires are broken and no connections areloose. vi) Clean the surface of the moving armature and magnet core which comes together when the contactor closes, free of dust or grease of anykind. vii) Examine the mechanical interlocks between the reversing contactor and see when the contact tips of one of the contactor units are touching, it is impossible to get the contact tips of the other unit totouch. viii) The contact tips should be kept free from burns or pits by smoothening with finesand paper or emerypaper. ix) Replace the contact tips which have worn awayhalf-way. x) Do not lubricate thecontacts. xi) Blow out windings thoroughly by clean and dry air to clear air passage in the stator and the rotor of any accumulated dirt. The air pressure shall not be too high to damage the insulation. xii) Examine earth connections and motorleads. xiii) Examine motor windings foroverheating xiv) Examine controlequipment‘s xv) Examine starting equipment for burntcontacts xvi) Check and tighten all nuts andbolts xvii) Clean and tighten all terminals and screw connections all contact surfaces shall be made clean andsmooth. xviii) Lubricate thebearings xix) Overhaul thecontrollers xx) Inspect and clean circuitbreakers. xxi) Wipe brush holders and check bedding ofbrushes. xxii) Blow out windings thoroughly by clean and dry air. The pressure shall not be so high that insulation may getdamaged. xxiii) Check the insulation resistance of the motor between any terminal and the frame. If the measured resistance is less than the prescribed value, then steps shall be taken to dry- out the motors either by passing a low voltage current through the windings or by placing the stator and rotor only in a warm dry place for a day orso.

Important: The complete motor shall never be put in an oven for drying as that may melt the grease out of bearings.

xxiv) Coat the windings with an approved high temperature resisting insulation enamel or varnish. xxv) Over haul the motor, ifrequired. xxvi) Check the switch fuse units and renew, ifrequired. xxvii) Check resistance or earthconnections.


81

xxviii) Check airgap.

Solenoids operated brakes

i) All fixing bolts shall be checked and tightened at least once in threemonths. ii) The magnet stroke should be reset to compensate forwear. iii) Re-adjust the brake when the magnet stroke reaches the value given on the instruction plate. iv) Brake lining should be checked and replaced whenrequired. v) Examine all electrical leads andconnections. vi) Rubber bushes or couplings should be checked and replaced ifdefective. vii) The pins should betightened. viii) Brake drum shall be cleaned to remove any dust orgrease.

4.3.10.3 Lifting beam and gantry crane for outletworks

a) Lifting beam Lifting beam shall be used for both raising & lowering of Spillway stop log units with the use of Gantry crane. Lifting Beam shall mainly comprise of two number structural steel channels or fabricated channels with back to back connection to make it a single fabricated structural frame. Two side guide rollers/shoes shall be provided on each side of the lifting beam. The depth of lifting beam/frame should be sufficient to accommodate to rollers on each side located at sufficient distance from one another to enable proper guided movement. The depth of lifting beam shall not be less than one tenth of the length/span of the lifting beam or 500 mm whichever is more. Lifting beam hook mechanism shall provide for automatic engagement and release of the equipment to be handled manually by movement of the hook block. The two hooks shall be mechanically linked together for simultaneous operation. All rotating parts of the lifting beam shall be provided with corrosion resistant steel pins and aluminum bronze bushing/roller bearings. All nuts, bolts and washers and retaining devices for pins shall be of corrosion resistantsteel. Following issues need to be considered and attended during maintenance; i) Bush bearing of lifting attachment and various pulleys/sheaves wheel gears etc. should be properlylubricated. ii) Whenever it is felt that friction in the bearing has increased, these should be taken out for cleaning and lubrication and should be refitted properly. These should be replaced, if found beyondrepair.

b) Gantrycrane Hoisting trolley of the Gantry Cranes are generally built on top of a wheeled mobile gantry structure travelling over fixed rails and is used to straddle an object or load over a workspace. The major component parts of the gantry comprise of the following: Frame & legs, machinery housing, operator‘s cabin, walkways, ladders and railings, end buffers, mechanical equipment, wheels and axles, gantry drive unit, wire rope, rope drum, gears and pinions, reduction gear box, shafts for gears and pinions, sheaves and pulleys, bearings,


82

flexible couplings, lifting hook and block, sockets for wire ropes, gear box covers, keys & key ways, counter weight, wrenches and tools, electrical equipment, electric motor, master control equipment, cables and cable reel, wiring ,limit switches, miscellaneous components etc.

Following aspects need to be considered and attended to during maintenance;

● Oil level in the gear boxes. It is very important to ensure that the correct oil level is maintained. Over filling causes overheating and leakage, therefore, care shouldbe taken that the breather holes are not clogged by any foreign material like dust, paint etc.

● The insulation resistance of motor winding. In case it is found to have dropped below a prescribed value, the motor should be dried prior to putting back in service. If weak insulation becomes a regular feature, the winding should be given a good coat of insulating varnish after the motor has beendried.

● Checking of all the electricalconnections. ● Lubrication of each part ofcrane ● Removal of any loose/foreign material along the railtrack ● Actuating tests of limitswitches ● Actuating tests ofbrakes. ● All fuses in the control panel should be checked and if necessary it should be

replaced. ● Necessary terminal connections of motors, brakes etc. is to bechecked. ● Overload relay should bechecked. ● Visual inspection of wire ropes for any snapped loose wire and its properlubrication. ● Checking of rope clamps on the drum and tightening of bolts ifrequired. ● Gearbox assembly should not have any leakage ofoil. ● Unusual noise/vibration if any should be checked and rectified beforeoperation.

Fig4.3a


83

Fig 4.3 b

Fig 4.3 a,b Gantry Crane

4.310.4 Surface preparation and painting of HM works i) Protection of painted surfaces is considered essential for protection & enhancement of service life. Gates, its embedded parts, gate leaf, hoists and its supporting structures need to be protected against corrosion due to climatic condition, weathering, biochemical reaction and abrasion etc. These equipment are likely to deteriorate/ damage to any extent that the replacement of parts may become necessary and such replacement may become difficult and costly. ii) Surface preparation & Painting requirements. Painting for hydro-mechanical works is to be carried out as prescribed in IS: 14177 for both newly manufactured as well as old & used gates, hoists and associated works after proper surface preparation. The preparation includes thorough cleaning, smoothing irregular surfaces, rusted surfaces, weld spatters, oil, grease, dirt, earlier applied damaged layers of primers/paint by use of mechanical tools, by use of solvents, wire brush etc. The sand/grit blasting process is used for surface preparation to a level of Sa 2½ of the Swedishstandard. iii) Surfaces not requiring painting & their protection during surface preparation, painting & transportation process.

a) The following surfaces are not to be painted unless or otherwisespecified: • Machine finished or similarsurface • Surfaces which will be in contact withconcrete • Stainless steel overlaysurfaces. • Surfaces in sliding or rollingcontact • Galvanized surfaces, brass and bronzesurfaces. • Aluminum alloysurfaces


84

b) The Surfaces of stainless steel, nickel, bronze and machined surface adjacent to metal work being cleaned or painted shall be protected by using sticky protective tape or by other suitable means over the surfaces not to bepainted.

c) All embedded parts which come in contact with concrete shall be cleaned as detailed above and given two coats of cement latex to prevent rusting during the shipment while awaiting installation.

iv) Application of primer & finish coats on embedded parts andgates a) Embeddedparts • The prescribed primer shall be applied as soon as the surface preparation is complete and prior to the development of surface rusting and within the specified time prescribed by Indian Standards or the Paint Manufacturer. In case there is lapse of considerable time beyond the prescribed time limit, the surfaces shall be again cleaned prior to priming. • Two coats of zinc rich primer with epoxy resin shall be applied to all embedded parts surfaces which are not in contact with concrete and shall remain exposed to atmosphere or submerged in water to obtain a dry film thickness of 75microns. • This shall be followed by three coats at an interval of 24hours of coal-tar blend epoxy resin so as to get a dry film thickness of 80 microns in each coat. Total dry film thickness of paint shall not be less than 300 microns. b) Gates Primer Coat - Over the prepared surface one coat of inorganic zinc silicate primer giving a dry film thickness of 70 ± 5 microns should be applied. Alternatively two coats of zinc rich primer, which should contain not less than 85% zinc on dry film should be applied to give a total dry film thickness of 75 ± 5 microns. Finished paint Two coats of solvent less coal tar epoxy paints. These shall be applied at an interval of about 24 hours. Each coat shall give a dry film thickness of 150±5 microns. The total dry film thickness of all the coats including primer coating shall not be less than 350 microns.

v) Hoist and supportingstructure a) Structuralcomponent Primer coats of zinc phosphate primer shall be applied to give a dry film thickness of 40±5 microns. Final Coats: One coat of alkalized based micaceous iron oxide paint to give a dry film thickness of 65 ± 5 microns followed by two coats of synthetic enamel paint confirming to IS: 2932 – 1974 to give a dry film thickness of 25 ± 5 microns per coat. The interval between each coat shall be 24hours. The total dry thickness of all coats of paint including the primer coat shall not be less than 175 microns.

b) Machinery: Except machined surfaces all surfaces of machinery including gearing, housing, shafting, bearing pedestals etc., shall be given: Primer coats: One coat of zinc phosphate primer paint to give minimum film thickness of 50 microns. Motors and other bought out items shall be painted if necessary. Finished coats: The finished paint shall consists of three coats of aluminum paint confirming to IS: 2339 – 1963 or synthetic enamel


85

paint confirming to IS: 2932 – 1977 to give a dry film thickness of 25±5 microns per coat to obtain a total minimum dry film thickness of 125microns.

c) Machinedsurfaces All machined surfaces of ferrous metal including screw threads which will be exposed during shipment or installation shall be cleaned by suitable solvent and given a heavy uniform coating of gasoline soluble removable rust preventive compound or equivalent. Machined surfaces shall be protected with the adhesive tapes or other suitable means during the cleaning and painting operation of othercomponents.

vi) Application ofpaint Mix the contents thoroughly as directed by paint manufacturer before and during use. Painting at shop can be done by any of the three methods namely Brush/roller, Conventional spray, Airless spray etc. The paint can be made to suit the adopted method. But once the gate and equipment is in erected position the general method adopted is only brush / roller. In case of spray lot of precautions are to betaken. For More details: Refer IS: 14177 Part (II) – 1971. Appendix A – Brushing of paint Appendix B – Spraying ofpaint Appendix C – Spray painting defects: Causes and remedies. Removal of old paint / rust and carrying out fresh painting: The carrying out of fresh painting is to be considered under the following conditions: • The rusting is noticed all over the surfaceor • Rusting is severeor • Cracking and blistering has damaged the primer coat exposing the metal and is noticed all over the surfaceor • The paint film has eroded badly, the scrap of entire paint film to the base metal and carry out freshpainting. Note: In case of maintenance and renovation: Refer IS: 14177 (Part II) – 1971 for checking and repainting.

vii) Removal of old paint for repainting - Caution should be exercised whileremoving the old paint. The surfaces shall be de-rusted and descaled by either mechanically by one or more of the methods, namely: a) Wire brushing, Scraping, and chipping. Sand papering or cleaning with steel wool or abrasivepaper b) Power toolcleaning c) Flamecleaning d) Sand blasting or shot blastingand e) Chemical rust removal. Note: The method of application shall be decided based on conditions existing. After cleaning painting is to be carried out as originally proposed. Some are painted without removal of old paint and rusting this will amounts to no painting and deteriorate faster than the original one.


86

viii) Inspection and testing of painting of H. Mworks a) The following steps are involved in inspection ofpainting:

● General inspection before and duringpainting ● Viscosity test ofpaints ● Paint thickness test-usingElcometer. ● Inspection of general appearance of finishedwork.

b) General The aim of inspection and testing is to ascertain whether the recommended practice is being employed correctly during every stage of application and whether the final results fulfill the object of painting. Any test carried out should be of non – destructive nature or, if it is of destructive nature, it should be either restricted to areas which can be restored without marring the general appearances, or be such that it is possible to restore easily without necessitating a complete repetition of thework. c) Inspection of surfaces prior to painting- Inspection methods will depend on whether it is to be painted for the first time or is to be repainted.

d) New Works (not previouslypainted). The following shall be decided by inspection:

● The method of pre cleaning feasible orrecommended; ● The intermediate protective treatments to be applied, if found necessary; ● The final painting schedule and the specifications for the paint for ensuring the

particularperformance; ● The method of application, whether by brush, roller orspray.

e) Old Work (which requiresrepainting) The following shall be decided by inspection:

● Whether the entire existing paint requires removal;and/or ● Whether repainting without paint removal would beadequate.

4.3.11 Electricalsystem Electricity is typically used at a dam for lighting and to operate the gates, hoists, recording equipment, and other miscellaneous equipment. It is important that the Electrical system be well maintained, including a thorough check of fuses and a test of the system to ensure that all parts are properly functioning. The system should be free from moisture and dirt, and wiring should be checked for corrosion and mineraldeposits.

All necessary repairs should be carried out immediately and records of the works kept. Maintain generators used for auxiliary emergency power - change the oil, check the batteries and antifreeze and make sure fuel is readily available.

Monitoring devices usually do not need routine maintenance. Open areas are particularly


87

susceptible to vandalism. As such all electrical fittings like bulbs, lights, loose wires etc. in open areas should be checked routinely and replaced/repaired where needed. The recommendations of the manufacturer should also be referred to. 4.3.12 Metal component maintenance

All exposed, bare ferrous metal of an outlet installation, whether submerged or exposed to air, will tend to rust. To prevent corrosion , exposed ferrous metals must be either appropriately painted (following the paint manufacturer‘s directions) or heavily greased in respect of moving parts & on surfaces like guides & track seats on which there is movement of gates. When areas are repainted, it should be ensured that paint is not applied to gate seats, wedges, or stems (where they pass through the stem guides), or on other friction surfaces where paint could cause binding. Heavy grease should be applied on friction surfaces to avoid binding. As rust is especially damaging to contact surfaces, existing rust is to be removed before periodic application of grease.

4.3.13 Accessroads For a dam to be operated and maintained there must be a safe means of access to it at all times. Access road surfaces must be maintained to allow safe passage of automobiles and any required equipment for servicing the dam in any weather conditions. Routine observations of any cut and fill slopes along the sides of the road should be made. If unstable conditions develop assistance of experienced Engineers/Expert Panels should be obtained and remedial measures initiated. Drains are required to be provided and maintained along roads to remove surface and subsurface drainage. This will prolong the life of the road and help reduce deterioration from rutting. Road surfacing should be repaired or replaced as necessary to maintain the required traffic loadings. In most cases, specialized contractors will be required to perform this maintenance.

4.3.14 General cleaning For proper operation of spillways, sluiceways, approach channels, inlet and outlet structures, stilling basin/ energy dissipation arrangements, discharge conduit, dam slopes, trash racks, debris control devices etc., regular and thorough cleaning and removal of debris is necessary. Cleaning is especially important after large floods, which tend to send more debris into the reservoir.

4.4 Materials requirements for maintenance during monsoonperiod For both immediate maintenance and preventive maintenance should be stocked in adequate quantity depending upon the size of the project and requirements. Needful instructions in this regard need to be enclosed in the O&M Manual. In Indian dams, normally a 24x7 hour patrolling is to be carried out during monsoon period. The materials normally required to be stocked in sufficient quantity are:-

● GunnyBags ● Sand ● Boulders/Wirecrates ● Bamboos/Balli‘s


88

● Baskets ● Ropes ● Petromax Lamps withSpares ● Torches with sparecells ● KeroseneOil ● Match Boxes ● Rain Coats ● GumBoots ● Warning signindicator ● Danger zonelights

4.5 Establishmentrequirements The requirements of annual and monsoon establishment for the operation and maintenance

of a dam is to be decided by the Dam Owners on a case to case basis. The staff requirements

would vary from project to project depending upon its size, importance and hazard potential.

4.6 Preparation of O&Mbudget In order to prepare O&M budget for a dam project all possible costs associated with

implementation of O&M Program need to be identified and considered. Typical O&M budget

for a project should essentially include but not limited to the following items:

i) Establishment Cost of Regular Staff - Salaries and allowances, Bonus, Medical

Reimbursement, LTC, Leave Encashment, pension benefits, etc. (asapplicable).

ii) Establishment Cost of Work charged Staff - Salaries and allowances, Bonus, Medical

Reimbursement,

LTC, Leave Encashment, Pension benefits, TA and DA , etc. (as applicable).

iii) Establishment Cost of Daily wage Staff - Salaries and allowances, TA and DA etc. (as

applicable).

iv) Office Expenses – Rent for office, Telephone/Mobile/any other Telecommunication

bills, Electricity bills, water bills, Office stationery, Day to day officerequirements.

v) Motor Vehicles - Running and Maintenance cost of inspection vehicles, Cost of hiring of

vehicles asrequired

vi) Maintenance of Colony - Maintenance of staff quarters, colony roads, Electricity, Sanitary

and Water supply systemsetc.

vii) T&P - T&P requirements for offices, colony, works etc. asapplicable.

viii) Works -Painting, oiling, greasing, overhauling of HM equipment’s, Repair/replacement

of gates seals & wire ropes , POL for pumps & generator sets, Electricity charges and

maintenance of Electric systems of dam site, specific requirements for all Civil , H.M &

Electrical maintenance works, vegetation removal and mowing of turfing on earth dams,

maintenance/cleaning of drains in dam, maintenance of lift/elevators in dam (as applicable),

maintenance of access roads & basic facilities, provision for flood contingencyworks

during monsoon, unforeseen events/items (about 10% of the cost of works) etc


89

Table 4.1 - O&M BUDGET COSTS (ANNUAL)

SL.NO.

BUDGET ITEM

PREVIOUS

YEAR COST(Rs)

CURRENT YEAR

BUDGET(YR )(Rs)

REMARKS

A. ESTABLISHMENT

1 SALARY OFREGULARSTAFF

INCLUDING ALL OTHER BENEFITS

2 TRAVEL EXPENSES

3 OFFICE EXPENSES

4 MOTOR VEHICLE EXPENSES

5 MAINTENANCE OFOFFICE

&COLONY

SUB-TOTAL - A

B. WORKS 1 CIVIL

1.1 CONCRETE / MASONRY DAM

1.2 EARTHEN DAM

1.3 INTAKE / OUTLETSIN

EARTHEN DAMS

1.4 SLUICES IN CONCRETE / MASONRY DAMS

1.5

APPROACH/ INSPECTIONROADSWITHIN

DAMAREA

2 HYDRO-MECHANICAL

2.1 SPILLWAY GATES & HOISTS

2.2 SPILLWAY STOP-LOG & GANTRY CRANE

2.3

OUTLETS INEARTHENDAMS SERVICE/EMERGENCYGATES

&HOISTS

2.4

SLUICES INCONCRETE/ MASONRYDAMS –SERVICE

/EMERGENCY GATES&HOISTS

3 ELECTRICAL

3.1

ELECTRICALFITTINGS, MOTORS,CONTROLS FORALL

GATEHOISTS

3.2 POWER SUPPLY LINES

3.3 ELECTRICAL FITTINGS ON DAM TOP, DAM GALLERIES,ETC.


90

3.4 STANDBY POWER /DIESEL

GENERATOR

3.5 REMOTE CONTROL/CCTV

4 INSTRUMENTATION

5 MISCELLANEOUS WORKS

6

SALARY OF WORKCHARGED STAFF INCLUDING ALL BENEFITS

7 MATERIALS TO BESTORED BEFORE MONSOON

SUB-TOTAL - B

8 CONTINGENCY (10%) ONSUB- TOTAL OF A & B

9 TOOLS & PLANTS

SUB-TOTAL- C

10 TOTAL ANNUAL COST

4.7 maintenance of records– A record should be kept of all maintenance activities, both immediate and preventive maintenance works. Information that should be recorded includes the following as a minimum:

● date and time ofmaintenance, ● weatherconditions, ● the type ofmaintenance, ● name of person or contractor performingmaintenance, ● description of workperformed, ● the length of time it took to complete the work with dates, ● equipment and materials used,and ● before and afterphotographs.

The data should be recorded by the person responsible for maintenance.


91

Chapter 5. INSTRUMENTATION AND MONITORING

The program must be based on prevailing geotechnical conditions at the dam, and must include consideration of the hydrologic and hydraulic factors present before and after the project is in operation. Instrumentation designed for monitoring potential deficiencies at dams must consider the threat to life and property that the dam presents. Thus, the extent and nature of the instrumentation depends not only on the complexity of the dam and the size of the reservoir, but also on the potential for threat to life and property losses downstream. Continued monitoring is important to monitor the efficacy of the remedial works carried out. The involvement of personnel with experience in the design, installation, regular monitoring, and evaluation of an instrumentation system is of prime importance to the success of theprogram.

Instruments installed at a dam can indicate occurrence of any anomalous or problematic behavior. They can show that whether the dam behavior is as per design or otherwise. Actual measurements of uplift pressure in a Gravity dam and comparison with the uplift pressure assumed in original designs is an example.

5.1 General Instrument types The parameters often monitored by instruments include:

● movements (horizontal, vertical, rotational andlateral); ● pore pressure and upliftpressures; ● waterlevel; ● seepageflow; ● waterquality; ● temperature; ● Crackwidth; ● seismicactivity; ● weather and precipitation data;and ● stress andstrains.

5.2 Instrumentation at MalampuzhaDam

The following instruments are installed at the dam and their status is as under:

1 Water level

2.V-Notch in Gallary

3.V-Notch in Earthen dam

4.Raingauge

5.2.1 Parametersmonitored

i) Waterlevel Water level gauge is provided near A point of the dam. Daily water levels are


92

taken . During monsoon, hourly readings are taken and recorded. ii) Seepage in the foundationgallery

In Malampuzha dam the porous drains and foundation drain holes are connected to the common drain in foundation gallery

iii) Seepage in the Earthendam Downstream of earthen dam V-Notch is provided to measure excess seepage in the earthen dam

5.3 Frequency of Monitoring

Water level is monitored daily and the instruments readings are taken as specified.

Seepage assessment In Malampuzha Dam, there are ---- Porous drains and --- Foundation Drain Holes. Monthly observations of these holes are being carried out. Total seepage is measured using V-notch fitted in the foundation gallery. Seepage details for the following previous years are tabulated below.

Year/Date Reservoir Water V notch reading (cm) Discharge(Litres/min)

5.4 Data Processing andEvaluation The steps required to process and evaluate data, whether collected manually or automatically, are the same. Instrument data should be processed and evaluated according to the procedures established by the monitoring program. Accumulation of instrument data by itself does not improve dam safety or protect the public.

Monthly reports are prepared for evaluation in case of Malampuzha dam

5.4.1 DataCollection Data collected manually should be recorded on the data sheets prepared as part of the monitoring program. Complementary data, such as air temperature, reservoir level, reservoir temperature, recent precipitation, and other information or observations that may be important in evaluating the instrumentation data should be noted on the datasheets.

Data collection for the dam is carried out on daily, fortnightly / monthly basis as the case may be.

5.4.2 DataPresentation All data should be summarized in graphical form. All plots should include sufficient previous data to identify any long-term trends. Furthermore, the plots should be self explanatory.

5.4.3 DataInterpretation Data should be reviewed for reasonableness, evidence of incorrectly functioning instruments, and transposed data. Several checks for reasonableness can be made on all data. The


93

magnitude of data should be near the range of previous data. Data that are significantly different may be incorrect. All data will have scatter from instrument error, human error, and from changes in natural phenomena such as temperature, wind, and humidity. The true accuracy of data will not be apparent until a significant number of readings have been taken under a variety of conditions. All data will follow trends, such as decreasing with time or depth, increasing with time or depth, seasonal fluctuation, direct variation with reservoir or tail water level, direct variation with temperature, or a combination of such trends.

Interpretation of data is carried out as per standard practice & on monthly / six monthly / yearly basis or as decided by design authorities for this dam.

Interpretation of data, so collected, needs to be carried out judiciously. Help of experienced personnel from the concerned field from Institutes / manufacturers / instrument suppliers could prove to be useful.

5.4.4 Dam PerformanceEvaluation The purpose of instrumentation and monitoring is to maintain and improve dam safety. The data should be used to evaluate whether the dam is performing as expected and whether it provides a warning of developing conditions that could endanger the safety of the dam. All data should be compared with expected behaviour based on the basic engineering concepts. Variations from expected behaviour may suggest development of conditions that should be evaluated. All data should be compared with design assumptions. If no unusual behaviour or evidence of problems is detected, the data should be filed for future reference. If data deviates from expected behaviour or design assumptions, action should be taken. The action to be taken depends on the nature of the problem, and should be determined on case-by-case basis. Possible actionsinclude:

● Performing detailed visualinspection; ● Repeating measurements to confirmbehaviour; ● Re-evaluating stability using newdata; ● Increasing frequency ofmeasurements; ● Installing additionalinstrumentation; ● Designing and constructing remedialmeasures; ● Operating the reservoir at a lower level;and ● Emergency lowering of thereservoir.

5.4.5 Methods of BehaviorPrediction Each dam is a unique structure and has its own special conditions of siting, design, construction and operation. Rigorous methods of prediction have been developed over the years. These methods apply the laws of physics to problems of slope stability, foundation stability and rock deformation. Modern solutions use finite element or finite difference models run on computers. Such numerical analyses are expensive and for that reason are generally used only for larger dams. Special analyses are made when investigations reveal weak materials or otheranomalies.

5.5 VisualObservations


94

Observations by on site personnel (dam owners/operators and maintenance personnel) may be the most important and effective means of monitoring the performance of a dam. An inspector, upon each visit to the dam site, should examine it visually – walking along the dam alignment and looking for any signs of distress or unusualconditions.

August 2020

Chapter6. REMEDIAL MEASURES TAKEN EARLIER

Before DRIP, maintenance activities were limited to routine repair of electrical systems for hoisting system of Emergency gates of out let and valve operations; gallery drainagmowing, vegetation removal, repair of dam top road and allied works etc. Apart from these routine maintenance activities, no major rehabilitation was carried before the involvement of DRIP. Under DRIP, following Rehabilitation Works have been caThe rehabilitation works under DRIP include: Proposals made in twocategories

Safety- intended to enforce structural safety of thestructure

Rehabilitation of the Dam• Maintenance woks of all weather accessroads,• Formation of new roads and approaches todam• Improvements to existingroads• Protective measures- Construction of compoundwall• Boundarydemarking • Improvements to existing BoatJetty• Repairs of Dam Pavilion and SurroundingStructures• Improvements to informationCentre• Construction of Control room• Construction of Seismograph Stationbuilding• Renovation of Downstream face• Repairs to apron downstream ofspillway• Guniting to the water face ofDam.• Rectification of damaged downstream slope• Renovation of upstream rip

PHOTOGRAPHS OF THE REHABILITATION WORKS (Before & After)1. All weather access roads and approaches toDam

Before

O&M Manual of

REMEDIAL MEASURES TAKEN EARLIER

Before DRIP, maintenance activities were limited to routine repair of electrical systems for hoisting system of Emergency gates of out let and valve operations; gallery drainagmowing, vegetation removal, repair of dam top road and allied works etc. Apart from these routine maintenance activities, no major rehabilitation was carried before the involvement of

Under DRIP, following Rehabilitation Works have been carried out or under progress. The rehabilitation works under DRIP include:

Proposals made in twocategories- intended to enforce structural safety of thestructure

Rehabilitation of the Dam- rectifying damage to the damcomponentsll weather accessroads,

Formation of new roads and approaches todam Improvements to existingroads

Construction of compoundwall

Improvements to existing BoatJetty Repairs of Dam Pavilion and SurroundingStructures

vements to informationCentre Construction of Control room Construction of Seismograph Stationbuilding Renovation of Downstream face- toedrain Repairs to apron downstream ofspillway Guniting to the water face ofDam. Rectification of damaged downstream slope of earthendam Renovation of upstream rip-rap of damslope

PHOTOGRAPHS OF THE REHABILITATION WORKS (Before & After) All weather access roads and approaches toDam

After

O&M Manual of Malampuzha Dam

95

REMEDIAL MEASURES TAKEN EARLIER

Before DRIP, maintenance activities were limited to routine repair of electrical systems for hoisting system of Emergency gates of out let and valve operations; gallery drainage; routine mowing, vegetation removal, repair of dam top road and allied works etc. Apart from these routine maintenance activities, no major rehabilitation was carried before the involvement of

rried out or under progress.

rectifying damage to the damcomponents

August 2020

2. Protective Measures-Compound wall around the Dam, Saddle dam and boundary area

3. Reservoir area boundary demarking, Protectivemeasures

4. Improvements to the Existing Boat jetty, Strengthening the side

At Thonikadavu and improvements to existingsteps

Before

O&M Manual of

Compound wall around the Dam, Saddle dam and boundary

Reservoir area boundary demarking, Protectivemeasures

Improvements to the Existing Boat jetty, Strengthening the side pitching At Thonikadavu and improvements to existingsteps

After


96

Compound wall around the Dam, Saddle dam and boundary

After

August 2020

5. Repairs to Dam Pavilion and surroundingStructures

Before

6. Improvements to the existing InformationCentre

7. Construction Of ControlRoom

Before

O&M Manual of

Repairs to Dam Pavilion and surroundingStructures

After

Improvements to the existing InformationCentre

Construction Of ControlRoom

After


97

August 2020

8. Construction of Seismograph station

9. Guiniting to the water face ofDam

Before

10. Renovation of upstream rip rap including

Before

O&M Manual of

Construction of Seismograph station Building

Guiniting to the water face ofDam

After

Renovation of upstream rip rap including repairs to the damaged area of damslope

After


98

repairs to the damaged area of damslope


99

Chapter 7 . UPDATING THE MANUAL

As features of the dam and appurtenant structures change occasionally, the O&M Manual must be edited and portions rewritten to reflect these changes. This important task is often ignored. Updating information in the O&M Manual should be done whenever major changes like construction of an additional spillway, construction of dam on the upstream etc. take place. Aspects to be considered when updating include:

● Increase/decrease in the frequency of an inspection or the maintenance routine based on additional data/ experienceacquired.

● Changes in the operation and/or maintenance procedures based on additional data/experienceacquired.

● Alterations to the project data because of changes/modifications in the dam by way of additional spillwayetc.

All up-dates/revisions of the O&M Manual need to be sent to all the locations/addresses to whom the copies of the original O&M Manual had been sent earlier. It is recommended that O&M Manuals be reviewed/ updated after every 10 years by the respective Dam Owners.


100

Annexure –1 BasicDrawings

Drg 1.1Non over flow section


101

Drg 1.2 Spillway Section


102

Drg 1.3Earthen Dam Sections


Drg 1.4 LAYOUT PLAN OF DAM


104

Annexure–2 HydrologyReview

REPORT OF DESIGN FLOOD REVIEW


105


106


107


108


109


110


111


112


113


114


115


116


117

Annexure -3-Inspection Report in Earlier Format PROFORMA FOR PERIODICAL INSPECTION OF LARGE DAMS

A. GENERAL Date of Inspection Report :

Sl. No.

Item Remarks

1

2 3 4 5 6

7

8

(a) (b) (c)

(d)

(e)

(f)

(g) (h) (i)

Name of Project

Purpose of Project Name of Dam First filling (year /level) Year of completion Benefits accrued

MALAMPUZHA IRRIGATION PROJECT Multi-purpose MALAMPUZHA 1955 1966

a b c d

Irrigation. Water supply Power Other benefit

Important Controlling Levels (in metre) Top of dam Maximum water level Full reservoirlevel

Sill level of irrigation sluice

Sill level of scouring sluice

Spillway crest level

Maximum draw down level Lowest river bed level Deepest foundation level

Important Salient Features

(a)

(b) (C)

(d)

(e)

(f)

Dead storage capacity

Area of foreshore at FRL

Design flood adopted (PMF/SPE/Any other) give relevant magnitude

Design spillway discharge capacity and type ofspillway

Type, number and size of spillway gates

Location, sill level and capacity of low level outlets and scouring sluices

(g) Height of Dam in meters

(i) Above deepestfoundation (ii) Above lowest riverbed


118

(h) Gross storage capacity in Mm3

(i) At FRL (ii) At MWL (ii) Length of dam (at crest) in metres

9 Name and designation of the Inspecting Officer

10 Date of inspection and corresponding water level

11 Maximum and minimum water level reached during the last season with dates

12 Maximum overflow during preceding monsoon with dates

13 History of past distress, if any, and brief details of remedial measures carried out.

Does the officer in charge of the operationand 14 maintenance of dam posses all the records as

given in Annexure -1

15 When and by whom was the dam inspected immediately proceeding this inspection ?

Are the items pointed out during the last 16 inspection properly attended to ? (If not, state

deficiencies yet to be corrected)


119

INSPECTION OF DAMS AND ANCILLARY WORKS B. EARTH DAM

Item No. (1)

Item of Inspection

(2)

Observations and recommendations

if any, of the Inspecting Officer

(3)

Remarks of

Reviewing Officer

(4) 1 Down stream drainage

(a) (b)

(c)

Are there any signs of water logging, slushy conditions or growth of aquatic weeds on the downstream of the dam ?

Are there any standing pools of water in the down stream area of dam ? If so, give their locations and extent.

Are there any boils observed in the vicinity of down stream toe of the dam ?

Is the down stream area sufficiently clear and free draining?

What is the depth of ground water table on the down stream as evident from the existing wells in the vicinity of the dam ? Does the water table show any marked variation in accordance with the variations in reservoir water level ?

Are all the exposed drains working satisfactorily? Toe Drains and Cross Drains

Are the portions of longitudinal toe drain and

(i) exposed cross drains beyond the down stream toe of the dam in regular sectionsand freely draining

(ii) Is the pitching to these drains are intact?

(iii) Is there any weeds growth in these drains?

(iv) Indicate other defects noticed in these drains ifany

Outer Fall Drain

(d)

(e)

(f)

(g) (h)

(i) (ii)

Is the outer fall drain in proper shape and grade and freely draining ? Is the outer fall drain properly cleaned and maintained ?


120

(iii) Does the outer fall drain show any stagnant pools of water or weeds growth ?

2 Surface drainage of down stream slope (a) Is the condition of down stream slope drainage

arrangements satisfactory ?

(b) Is the paving to these drains intact ?

(c) (d)

Are all the drains are properly maintained and free from vegetation and debris ? Does the slope have a tendency to develop severe rain cuts at any location ?

(e) Enumerate any other defects noticed in the surface drainage of down stream slope.

3 Seepage measurements

(a) Is the quantity of seepage being daily or periodically measured with respect to water level in reservoir and recorded ? Please check the registers and record observations.

(b) Does it show any abnormal rise or fall ? If so, does

it have any relation to a certain reservoir level alteration?

(c) Does the seepage flow show a turbid colour at any stage ? Was such phenomenon observed at any stage at any location in the past ?

(d) What is the measured rate of seepage flow with date and reservoir level

(i) On the day of present inspection (ii) Maximum since lastJune (ii) Minimum since lastJune (e)

Is the portion upstream and down stream of measuring points of seepage easily accessible with proper steps and path and free of vegetation growth

(f) Are the measuring points properly located , constructed and maintained so as to give accurate and reliable measurements of seepage?

(g) Is the method of taking seepage measurements satisfactory ?

(h) What is design seepage discharge ? State your observations on comparison.


121

4 Earth dam section crest (a) Is the crest profile at proper elevation ?

Does it show any sign of excessive and or uneven settlement ? If so, indicate such locations and extent of settlements ( surface settlement point must be installed for observing thisaspect)

(b)

Is the surface of the crest free from undulations and local depressions or heaving ?

(c)

Does it develop any visible crack in tranverse or longitudinal directions ? If so attach a map showing their locations and extent. Depth and width of cracks must be ascertained by taking open trenches extending below the bottom ofcracks

(d) What is the condition of the edges of crest ? Is ramp

provided ? Any road crossing provided ? Have they got eroded and cut up resulting in reduced effective width ?

(e) Is the crest is free from local slip through out its length on either side?

(f) Do the headers, guard stones and parapet wall provided all the edges of the crest are in proper profile and plumb?

5 Earth dam section - Upstream and downstream slopes

Indicate the general condition of upstream pitching, down stream pitching, turfing and rock toe.

(a) Do the upstream and downstream slope show any

sign of bulging or concavity ? If so, indicate their locations and extent.

(b)

Do the section of the dam and both slopes appear structurally sound and stable ?

(c)

Are any longitudinal and transverse cracks noticed in any part of the slopes ?


122

(d) Were any signs of distress to stability of slopes noticed at any time in any part of the dam ? If so, give brief details of the incidents and location, the method of treatment adopted and its effectiveness.

(e) Is there any profuse growth of bushes or weeds over any portion or the dam ? If so indicate the locations.

(f) Do the upstream and downstream slope show existence of crab holes or holes made by rodents or burrowing animals or anthills ? If so indicate location.

(g)

Are there any wet or slushy patches and concentrated leak springs or trickles observed on downstream slope or toe. If so indicate their location and extent. Please look out for patches of extensive vegetation growth and examine them care fully and record yourfindings.

(h)

Are all the rain cuts and erosion channels properly treated and made good ? Please indicate location of recurring damages if any.

6 Junction earth work with masonry/ concrete dam sections and outlets.

(a) Is there any existence of leakage springs wet spots in the earth work in the vicinity of junctions between the earth work and masonry work ? If so what is the approximate rate and colour of leakage ? Does it turn turbid at any time ? Please ascertain from enquiries and record the findings.

(b) Is there any tendency for separations, cracking,

settlement or upheaval of earth work in the vicinity of masonry or concrete ? If so indicate the locations and exact nature of deficiency.

(c)

Is there any tendency for surface erosion at the junctions?

(d)


123

(e)

If the outlet conduit is located in the earth dam section, is the entire length of conduit in perfect order and profile and free from offsets, open joints, cracks and leakage. Examine the conduit care fully from the downstream or from inside if possible and indicate deficiencies observes if any.

Check the conditions of the crest andslopes especially in the zones adjacent to concrete structures. Detect the deformations settlement cracks or other distress conditions caused by external erosion due to wind, rain etc. Set up permanent observation system for the same at the places of occurrence. Seepage at junctions between earth dam and masonry or concrete retaining wall or arch type junctions with concrete dams is a possible sources of trouble and should be carefullywatched.

7 Reliefwells (a) Are the relief wells in good working condition and

functioningwell? (b) (b)

(c) (c)

(d) (d)

Are the relief wells properly cleaned periodically ? Please indicate the dates of last cleaning and next cleaning due.

Are the necessary plant and equipment for cleaning the relief wells, available with the office.

8 Breaching section (Ifprovided) (a) Is the breaching section easily accessible? (b) Is the condition of breaching section issatisfactory

? (c) Is the note of instructions as to when and how to

operate the breaching section available on record? (d) For reconstruction after the breach are the following

items decided in advance? (i) Quarry for embankmentmaterial

(ii) Suitable routes ofaccess. (iii) Agency, plant and machinery for its

reconstruction (e) Is the maintenance staff fully aware of the

instructions of (c) and (d) above?

(f) (f)

(g) (

g)

(h) (h) (i) (i)


124

(j) (j)

Notes:

Ascertain and indicate the latest event of operation of breaching section and its performance.

Is the surplus course from the breaching section acquired up to natural valley ?

Is the course formed ?

Is the surplus course assigned later as agriculture land or house site ?

If so what steps are taken? For items pertaining to spillway gates, sluices and

outlet etc. please refer points 4, 5, 6, 7, 8, 9, 11, 12, 13, 14 under masonry / concrete dam.


125

PROFORMA FOR PERIODICAL INSPECTION OF DAMS C. MASONRY / CONCRETEDAM

Item No. (1)

Item of Inspection

(2)

Observations and recommendations

if any, of the Inspecting Officer

(3)

Remarks of

Reviewing Officer

(4) 1 Upstream and down stream faces

(a) Examine the monolith and construction joints for such defects as cracks, open joints, spalling, seepage leaching etc. and indicate their findings.

(b)

Is the upstream face of dam in good condition ? If not indicate the nature and extent of deficiency.

(c) Is any spalling or cracking observed on the down stream face especially near the zone of concentration of stresses like the location of abrupt change in geometry, or at the opening ? If so, indicate the details of observations ?

(d) (i) Are there excessive seepage/ sweating at any location on down stream face of dam ?

(ii) Whether the observations are analysed and compared with theoretical assumptions made in the design ?

(iii)

Remedial measures in case of large variation.

(e) Examine the roadway / top of the dam for offsets, opening of construction joints, condition of parapet wall, drainage, lighting etc.

2 Drainage gallery (a) General

(i) Is the drainage gallery easily accessible and does it have adequate lighting facilities with sufficient stand by units of lighting ? If not, indicate the deficiencies

(ii) Are proper arrangements made for the measurements of seepage into gallery?

Is the seepage from (a) porous pipes (b) Foundation drains (c) Monolith joints


126

(d) Other seepage location measured separately

(b)

(c)

(iii) Are the above arrangements satisfactory ?

Seepage from foundation (i)

(ii)

(iii)

(iv) (v)

Is there has been a substantial reduction in the seepage through the foundations. Is it due to choking of the drain holes ?

Are all the foundation holes periodically cleaned ? Indicate the last date of such cleaning and extent of variation observed in the seepage discharge before and after cleaning.

Are the measurements of uplift pressure taken regularly ? What was the uplift hike at highest reservoir level during last season ? Is observed uplift within design limits ? Are the seepage water and the deposit if any from the seepage being regularly examined for chemical combination ? If so indicate the result and the probable source of dissolved salts, if any.

Are the seepage water springs observed in the down stream area any where ? If so indicate the locations and state the physical nature of this seepage. Look out for such seepage spots particularly near the dykes fault zone etc. Ascertain if chemical tests are made of water samples from such springs for dissolved salts.

Seepage from body wall (Dam and Spillway)

(i)

(ii)

(iii)

What is the total seepage into gallery from the porous pipes in the dam at lake full condition ? How does it compared with seepage (for the corresponding water level) when the reservoir was first filled ?

If there has been a substantial reduction in this seepage ascertain and indicate the probable reasons therefore.

Is a statement showing the surface area of the dam (water side) calculated block wise for each meter of rise of water level available ?


127

(iv)

What was the total seepage per square meter of upstream face submerged during inspection ?

3

4

(v)

(vi)

(vii) (viii)

(ix)

(x) (xi)

Is there any excessive seepage from any body drain or any other location in the gallery ?

What steps are being taken for regular periodical cleaning of the porous pipes ?

Has there been a tendency for gradual reduction of drainage through pipes and progressive appearance of sweating on the down stream faces of dam ?

Has there been a considerable leaching from the seepage water and deposition of lime near seepage exit spots ?

Are the samples of seepage water and the reservoir water being regularly tested for reactive and corrosive properties ? Has the total leaching been estimated ?

Is the seepage on the downstream face of the dam measured ? What was the seepage on the date of inspection ? What was the maximum seepage during the past one year?

Structural performance (a) Are there any signs of structural distress noticed

on the dam spillway and foundation in the form of (i) (ii)

(iii)

(iv)

(v) (vi)

Excessive deflection. Tendency of gradual sliding.

Cracking and upheaval of settlement, if any, part of body wall or the foundation.

Excessiveuplift Excessive uplifting and leaching through the body of the dam and the foundation

Conspicuous weathering of materials of components in any portion of the body wall or the foundation

Spill way gates (Spill way gates and other gates wherever applicable) (a)

Are the following documents available at site?


128

(i) A complete set of detailed design calculations together with the drawings of gates, gate grooves embedded parts, hoisting mechanism and controlsetc.

(ii) Designer's operating criteria and /or detailed operating instructions for the various types of gates installed in the dam.

(iii) Maintenance schedules specifying each operation its frequency and for due and done dates

(iv) Operating instructions with "dos and don'ts" for all operationalunits

(b) Is the condition of steel surfaces and the surface paint deteriorated ?

(c) Are any connecting bolts of rubber seals loosened or damaged ?

(d) What is the general condition of the rubber seals ? Do any of the rubber seals show signs of weathering, hardening, cracking or tearing and damage ?

(e) Are the rubber seals of side and bottom touching uniformly all along the sealing surface?

(f) Do the rollers (Wherever applicable) touch the track plates uniformly ? Are the rollers lubricated ?

(g) Are the electrical meters, gear systems, limit switches, breaks, bush bearing etc. of hoist mechanism well lubricated ?.

(h) Is the operation of the above,smooth and satisfactory ? If not, list out individual results and observations.

(i) Are the embedded parts of the spillway gates, emergency gates and stop logs in sound condition and free from corrosion, uneven wear, cracking, chipping and dents? If not, state the nature of defects or defeciencies and observations, if any, regarding such defects.

(j) Check the following for structural soundness of all members and welded bolts and rivetted connections, uneven wear, uneven bearing, cracking, chipping and dents and indicate the findings

(i) Gate leaf andstiffeners


129

(ii) (iii) (iv) (v) (vi) (vii)

End arms Trunnion girders Stop logs Lifting beams Gantry cranes

Tracks

(viii) Bridge structures (k) Are the trunnion bearing of radial gates properly

lubricated ? (l) Is there any damage or weathering caused to

the seal plates ? If so indicate the nature of damage noticed

(m) Is the full length of wire rope of the hoist in sound condition and free from broken strands?

(n) (o)

Is the electrical wiring in sound condition ? Is the alternative power system for gate operation working properly ? Give the details of generating sets and stand by units and the time required to operate all gates on the alternative power system, on the basis of actual trial operation. Check for diesel stock for operation of generator, battery charger available, battery in spare etc.

(p) Is the operation which is standby in case of electrical hoists , tried and found satisfactory ? Please take test trial and ascertain.

(q) Are all the nuts of connecting bolts and anchorage properly tightened ? In case of trunnion girders anchorages tightening torque which is generally specified should be adhered to.

(Note : After inspection of various items it is necessary to draw up a list of actions needed to be taken and pursue matters with the concerned agency)

(r) Are the hydraulichoistsworking satisfactory?

(s)

(t)

Are the trunnion hub and the brackets well maintained ? Are the trunnions likely to get submerged during actual working of the spilway ? If so ascertain the causes for the same and specify. Please enquire for occurrence of such events ifany.


130

(u) Are any of the mechanical or structural components and fastening of seals subjected to excessive wear ? If so please give details. Is there any tendency for occurring damage to any particular components ? If so please give details.

(v) Is sufficient stock of spare which need frequent replacement maintainedatthe site ?

(w) If the staff posted at the site, maintenance and operation of gates, hoists equipment and electrical installation well experienced, fully trained and conversant with the job requirements and responsibilities?

(x) What is the exercising frequency ? When the gates were last exercised ?

(y) Performance during inspection

(z) Are Change over switches from main power supply to generator supply provided ?

5 Spill way bridges, hoist bridge, cat walks and other bridges where applicable.

(a) Are the decking, girders and structural supports of spillway bridge, hoist bridge and cat walks structurally sound ?

(b)

Is the floor of the bridge structurally sound and safe ?

(c) Is there satisfactory arrangements to prevent unauthorized entry into the control structures and bridges?

(d) Are the structural members and joints sound and free from corrosion ?

(e) When were steel components painted last ?

(f)

Is the surface of steel work and paint satisfactory ?

(g)

Is the parapet or rail over the bridges sound and safe?

(h) Are all the bearings, bearing pads and pier caps structurally sound ?


131

6

(i) Are all the track plates for entry cranes laid over such bridges structurally sound and intact ?

Energy dissipationarrangements

7

(a) (b)

(c)

(d)

Can tail pond be drained easily for inspection of stilling basin ? If not, what are the short comings ? Please ascertain and indicate the last event of inspection of stilling basin

From the examination of the levels and contour plans and reference marks in tail channel ascertain if there is a progressive erosion and retrogression in the tail channel. If so, indicate the extent and location of such erosion with reference to the various components of dam, spillway outlet, power house etc. ?

Is the concrete surface of the stilling basin and apron in good condition ? Are there any indication of pitting, cracking, spalling or wearing of the surface of the bed concrete ? If so, please give details of nature and extent of the damage.

Is there any indication of abrasion and cavitations damage (pitting of concrete) especially at friction block, chute block, the surface near the lower tangent point and the end still ? Ifso, please give the details of nature and extent of the damage.

(e) Is the under drainages of the stilling basin satisfactory ? Are the all open drain holes clear and functioning well?

Walls [Guide walls /divide walls, junction walls/ return walls/ splay walls etc. (strike out which ever is not applicable)] (a)

(b)

Is all the location of such walls accessible for inspection, maintenance and repairs ?

Is the drainage of back side of the walls (wherever applicable) from the weep holes satisfactory ? If not, indicate the nature of deficiencies.


132

(c)

(d)

Is there any tendency for the water to under cut the ends of the walls ? If so, please give the details of nature and extent of damage.

Is there any foundation erosion or scournoticed in the vicinity of such walls ? If so, please give the details of nature and extent of such damages.

8

9

10

(e)

(f)

(g)

Is there any surface erosion/damage caused to face or body of such walls ?

Do any of the walls show symptoms of unequal settlement, development of cracks and tilting ? If so, give details of defects noticed.

Is there any damage to guide bunds ? If so, give detailsof the damage.

End weir (i) Is it accessible?

Is there any erosion, pitting or spalling of (ii) the concrete or masonry surface ? If so,

give details (iii) Is there any scour noticed on the

immediate down stream of such weir ? If so, give details of location and extent of suchdamage.

Hydraulic performance of energy dissipation arrangements

(a)

(b)

Do the flow conditions in stilling basin have a tendency to draw rocky material into bucket and cause its churning and abrasion damage to the surface of buckets, baffle blocks, apron and end still ?

Is the hydraulic performance in proper agreement with result of model studies ? Ascertain the performance from the observed tail water rating curve and deficient observation of any, such as weep outs and excessive erosion under plunge pools and location of secondary rollers and retrogression.

Instruments installed and observations (a) Are all the instruments installed properly and

accessible ? Are all the instruments installed properly lighted, ventilated and adequately protected from possibilities of damages ?


133

(b)

(c)

(d)

(e)

Are all the instruments in proper working order ? Ascertain the case of instruments going out of order and indicate.

Are all the registers of observations posted up to date ? Please take test observations and initial theregisters.

Are all the plotting of instruments data completed up to date ?

Are sufficient stocks of spares, gauges, master gauges, stationery items etc. maintained at the site for uninterrupted data collections ?

11 Outlet (a)

(b)

(c) (d)

(e) (f)

(g)

(h) (i)

Is the vent periodically cleaned ?

Are there any damages to the intake walls, such as leakage noticed through walls ?

Is there any leakage observed through the conduit, concrete or masonry ? If so, give details of it's location and extent.

Is there any damages noticed to the conduit, concrete, breast wall and gate slots ?

Is the byepass valve (wherever provided) operating satisfactorily ?

Take operating trials of the following as provided and record the observations and defects noticed, if any

(i) Service -gates

(ii) Emergency -gates

(iii) Stop log -gates

(iv) Sluice -valves

Are the trashracks (wherever provided) cleaned before monsoon ?

Are there vibration and noise noticed in operation of the outlet gates at any time ? If so, are any periodical observation taken to ascertain their severity ?

Is the energy dissipation arrangements working satisfactorily for all discharges ?


134

12

(j) (k)

(l)

Is there any structural damage to the energy dissipation structures ? If so, give the details of nature and extent of damages.

Is the conduit structurally sound and reasonably leak proof ? If not, give details of nature and extent of the defects. Is it possible to examine the conduit from inside ?

Is there any seepage noticed around the conduit as ascertained from the observations of the downstream conditions ? If so, is it likely to cause (incase of earth dams) erosion and piping ?

Outlet gates (a)

(b)

Is the surface of the gates and paint deteriorated?

Are the connecting bolts of rubber seals loosened or damaged ?

(c) Do the rubber seals show signs of weathering and damage and need replacement ?

(d) Are the rubber seals of sides & bottom touching the bearing surface uniformly ?

(e) Do all the rollers touch the track plates ?

(f) Are all the rollers well lubricated ?

(g) Is the operation of outlet gates smooth ?

(h) Are the stem rods for liftingthegates straight?

(i) Are the actual operation and lifting and lowering of the gates and hoist mechanism smooth and satisfactory?

(j) Are all the gears and hoist mechanism well lubricated?

(k) Is the storing arrangement for emergency gate leaves and the stop logs in satisfactory condition ?

(l) Are the seal plates in sound condition ? If not ascertain the type of damage and indicate.

(m) Is the full length of wire rope (wherever applicable) of the hoist in servicable condition and free from any broken strands ?

(n) Are all the nuts of connecting bolts and anchorage properly tightened ?

(o) Are all the lifting beams in proper order and sound condition ?


135

(p) Do any of the mechanical or structural parts of

the gates, fasteners or hoists show signs of excessive wear ? If so, please give the details.

(q) Is there any tendency for recurring damage to

any particular component/s ? If so, give details.

(r) Is sufficient stock of spares which needs

frequent replacement maintained at the site ?

(s) Whether hand cranks are kept under lock and key and not attached on hoist mechanism when operated by electrical energy ? (t) Whether warning sign indicating "Danger, Do not

switch on" is hung during maintenance ?


136

(u) Whether operating crane is in 'A' condition and the operators instructed to lift the emergency gates/ stop logs in a vertical direction so that allowable carrying capacity is not exceeded ?

(v) Whether there is a standby power supply?

(w) The alternative source ofpower

(1) Is the generator in working condition?

(2) Frequency ofexercise (3) Is it developing full voltage? (4) Is the wiring intact? And the change over

switch in working condition? (5) Are the spares available at site?

13 River Outlet/ River Sluice &Gates (a)

Is the over all condition of river outlet works/ river sluices satisfactorily?

(b) Is the operation of the gates satisfactory as ascertained by taking an operating trial ? If not, indicate the defectsnoticed.

(c) Are the trashrack ( wherever provided) cleaned before monsoon?

(d) Is there excessive silting on the upstream of the sluice ?

(e) When were the gates last opened for desilting etc.

(f) (f)

Please indicate the approximate quantity of the leakage through the gates if any.

(g) Is there any seepage or leakage through conduit surface?

(h) (h)

Is there any damage to the upstream and down stream conveyance structures of the conduit.

(i) (i)

Is the condition of the energy dissipation arrangement satisfactory ?

(j) Is there is any retrogression noticed in the downstream channel ? If so, give details of nature and extent ofdamage.


137

14 Power Outlet (a) Is the over all condition of power outlet

satisfactory ? (b) Is the operation of the gates smooth and

satisfactory as ascertained by taking operating trials ? If not, indicate the nature of the defects noticed.

(c) Are the trashracks cleanedbefore monsoon?

(d) Is there excessive silting in the approach channel on the upstream of power outlet ?

(e) Is there any seepage through conduit surfaces ?

(f)

Is there any cavitations damage to the inside of the conduit and penstock of the HRT and pressure shafts?

(g) Are all the valves functioning properly ? (h) Are there any vibrations induced into the dam

and appurtenant works while the outlet is opened or the machines are running?

15 Emergency preparedness (a) Are the Project Officers well conversant with the

Emergency action plan, Reporting procedures, Warning procedures etc. ?

(b) When was the emergency action plan was last reviewed ?

(c) Are the communication directories updated ?

(d) Are the concerned authorities informed about the system of emergency reporting procedures and warning ?

(e) Are the inundation maps update ?

(f) Are available safety spots on the down stream of the dam identified and made known to the concerned authorities ?

(g) Is the communication system working satisfactorily ?

(h) Are adequate warning devices and facilities provided at the dam?

(i) Is the downstream warning system operational ?


138

(j)

(k) (k)

Are proper arrangements made for security of the dam and preventing cases of unauthorized tresspass, vandalism and sabotage to the dam works.

Is downstream warning system operatable on alternative power supply ?

16 Access roads (a) Is there a properly constructed and well

maintained all weather access road to the dam site ?

(b) What is the type of pavement of the access road and its condition?

(c) Are there properly constructed and well maintained access road arrangements to the following components for inspection, maintenance andrepairs?

(i) Top of dam

(ii) Spillway

(iii) Gates and Hoistingarrangements

(iv) Drainagegallery

(v) Bridgestructure

(vi) Down stream Stillingbasin

(vii) Junction andAbutments

(viii) Outlet ControlTower

(ix) OutletGates (x) Toe of earth dam - downstream drainage

arrangements andberms. (xi) All saddledams

(d) What is the general condition of all the structures on various access roads ? Are all the structures on the access roads adequately safe, for allowing passage of plant machinery for emergentrepairs ?

17 Communicationsfacilities (a)

Are the following facilities available at dam site ? (i) Wireless (ii) Telephone (iii) Telegraph

18 General assessment of condition of the dam Please give general assessment of safety of dam for normal operation. Please enumerate all your observation which you feel are adverse to the safety of the dam for normaloperation.


139

Annexure -4-Check list for Inspection

Composite Dam Checklist

SN

Inspection Item

Response Observations and Recommendatio ns, if any, of the authorized inspecting officer

Condition ( Unsatisfactory/Poor/F air/ Satisfactory

Y

N

N A

A-Reservoir A-1.1 General Condition

1.1.1

Is the reservoir water level unusually high or low?

1.1.2 Are there signs of decline in water quality?

1.1.3

Are there signs of recent sediment deposition?

1.1.4 Is floating debris present?

1.1.5

Any indications of major active or inactive landslide area in the reservoir rim? If so, indicate their locations and extent.

1.1.6

Are there people or livestock in and around reservoir?

1.1.7 Any other issues?

B-Dam and Dam Reach (Embankment) B-1.1 General Condition

1.1.1

Any major alterations or changes to the dam since the last inspection?

1.1.2

Is there any new nearby development in the downstream floodplain?

1.1.3

Any misalignment of poles, fencing or walls due to dam movement?


140

B-1.2 Upstream Slope

1.2.1

Any signs of bulging or concavity (depressions)? If so, indicate their locations and extent. (Check up the cross-sections with tape and level at random locations,at least two)

1.2.2

Does the section of the dam and upstream slope appear structurally sound and stable?

1.2.3

Presence of longitudinal or transverse cracks?

1.2.4

Any signs of distress to stability of slopes noticed at any time in any part of the dam? If so, give brief details of the incidents and location, the method of treatment adopted and its effectiveness. Indicate the general condition ofupstream pitching.

1.2.5

Any degradation to slope protection(riprap)?

N

1.2.6

Is there any profuse growth of bushes or weeds over any portion of the dam? If so, indicate the locations.

N

1.2.7

Does the upstream slope shows existence of crab holes or holes made by rodents or burrowing animals or ant hills? If so, indicate the locations.

N



141

N

B-1.3 Crest of Dam

1.3.1

Is the crest profile at proper elevation? (To be test checked at random locations by taking level)

1.3.2

Does it show any signs of excessive and/or uneven settlement? If so, indicate such locations and extent of settlement. (Surface settlement points must be installed for observing this aspect)

1.3.3

Is the surface of the crest free from undulations and local depressions or heaving?

1.3.4 Does it provide an all- weather road surface?

1.3.5

Any degradation to access road (sealed/unsealed)?

1.3.6

Does it develop any visible cracks in transverse or longitudinal directions? If so, attach a map showing their locations and extent. Depth of cracks must be ascertained by taking open trenches extending below the bottom of cracks.

1.3.7

Have the edges of the crest gotten eroded and cut up resulting in reduced effective width?

1.3.8

Is the crest free from local slips throughout its length on either sides?


142

1.3.9

Do the headers, guard stones and parapet wall provided at the edges of the crest appear in proper profile and plumb?

1.3.10

Any degradation to upstream parapet or downstream curb wall?

1.3.11 Evidence of livestock on dam crest?

N

1.3.12

Trees or profuse growth of weeds/bushes at any location?

1.3.13

Proper lighting arrangement at dam top?


B-1.4 Downstream Slope

1.4.1 Any signs of bulging or concavity (depressions)?

1.4.2

Are there any wet or slushy patches or any concentrated leaks, springs or trickles observed on the downstream slopes or the toe? If so, indicate their locations and extent. Please look out for patches of extensive vegetation growth and examine them carefully and record the findings.

1.4.3

Presence of longitudinal or transverse cracks?

1.4.4 Any signs of distress to the stability of slopes?

1.4.5

Are rain cuts/erosion channels present at any location?

August 2020

1.4.6

Are all the rain cuts and erosion channels properly treated and made good? Please indicate locationof

recurring damages, if any.

1.4.7

Is there any profuse growth of bushes or weeds over any portion of the dam?Ifso, indicate thelocations.

1.4.8

Does the downstream slope show existence of crab holes or holes made by rodents or burrowing animals or ant hills? If so, indicate the locations.

1.4.9

Any other degradation to slope protection (turfing)? Indicate the general condition of downstream pitching/ turfing and rock toe.

1.4.10

Is the downstream area clear of debris and freely draining?


B-1.5 Downstream Drainage

1.5.1

Are there any signs of water logging, slushy conditions or growth of aquatic weeds on the downstream of the dam? To be checked upto 300 m downstream of toe

1.5.2

Are there any standing pools of water in the downstream of dam? If so, give their locations and extent. To be checked upto 300 m downstream of toe


Is the downstream area

Downstream Drainage

the downstream of the

Malampuzha Dam

143


144

1.5.3

1.5.4

Are there any boils observed in the vicinity of the downstream toe of the dam? If so, give locations. Is the downstream area sufficiently clear and freely draining?

1.5.5

What is the depth of ground water table on the downstream as evident from the existing wells in the vicinity of the dam? To be checked upto 300 m downstream of toe.

1.5.6

1.5.7

Does the water table show any marked variation in accordance with the variations in reservoir water level? Are all the exposed drains working satisfactorily?

1.5.8 Toe drains and cross drains:

i. Are the portions of longitudinal toe drain and exposed cross drains beyond the downstream toe of the dam in regular section andfreely draining?

ii. Is the pitching to thesedrains intact?

iii. Is there any weed growth inthese drains?

iv. Any other defects noticed inthe drains?.

1.5.9 Outfall Drain:

1.5.12

(a) Is the outfall drain in proper shape and grade andfreely draining?

1.5.13

(b) Is the outfall drain properlycleaned and maintained?


145

1.5.14

Does the outfall drainshow any stagnant pools of water or weed growth?

B-1.6 Surface Drainage of DownstreamSlope

1.6.1

Is the condition of the downstream slope drainage arrangements,if provided, satisfactory?

1.6.2 Is the paving to these drains intact?

1.6.3

Are all the drains properly maintained and free of vegetation growth and debris?

1.6.4

1.6.5

Does the slope have a tendency to develop severe rain cuts at any location? Any other defects noticed in the surface drainage of downstream slope?

B-1.7 Seepage Measurement

1.7.1

Is the quantity of seepage being daily or periodically measured and recorded? Please check the registers and record observations.

1.7.2

Does it show any abnormal rise or fall? If so, explain if it has any relation to a certain reservoir level elevation.

1.7.3

Does the seepage show a turbid colour at any stage? Indicate if such a phenomenon has been observed at any stage, atany location in the past.

1.7.4

What is the measured rate of seepage flow with date and reservoir level:


146

i. On the day ofpresent inspection

ii. Maximum since last June

iii. Minimum since last June

1.7.5

Is the portion upstream and downstream of measuring points of seepage easily accessible with proper

steps and paths and free of vegetation growth?

1.7.6

Are the measuring points properly located, constructed and maintained so as to give accurate and reliable measurements of seepage in accordance with the relevant IS Codes?

1.7.7

Is the method of taking seepage measurements satisfactory?

B-1.8 Breaching Section (if provided)

1.8.1 Is the breaching section easily accessible?

1.8.2

Is the condition of the breaching section satisfactory?

1.8.3

Is the note of instructions as to when and how to operate the breaching section available on record?

1.8.4

For reconstruction after the breach, are the following items decided in advance?

a) Quarry for embankment material

b) Suitable routes of access


147

1.8.5

Is the maintenance staff fully aware of the instructions related to operation of the beaching section and for reconstruction after the breach ?

1.8.6

Ascertain and indicate the latest event of operation of breaching section and its performance.

1.8.7 Evidence of recent degradation?


B-1.9 Junction of Earth work with Masonry/Concrete dam sections and outlets

1.9.1

Is there any existence of leaks, springs or wet spots in the earth work in the vicinity of the junctions between earth work and masonry works? If so, please indicate the approximate rate and colour of the leakage and if it turns turbid at any time. Please ascertain from enquiries andrecord the findings.

1.9.2

Is there any tendency for separations, cracking, settlement or upheaval of the earth work in the vicinity of masonry or concrete? If so, indicate the locations and theexact nature of deficiency.

1.9.3

Is there any tendency for surface erosion or slope instability at the


148

1.9.4

junction? If the outlet conduit is located in the earth dam section, is the entire length of the conduit in perfect order and profile and free from offsets, open joints, cracks and leakage? Examine the conduit carefully from the downstream or from inside, if possible, and indicate the deficiencies observed, if any.


B-1.10 Relief Wells

1.10.1

Are the relief wells in good working condition and functioning well?

1.10.2

Are the relief wells properly surgedand cleaned periodically?

1.10.3

1.10.4

Please indicate the dates of last surging and cleaning and the next surging due. Are the necessary plant and equipment for cleaning the relief

wells, available with the office?

1.10.5

Is the record of periodical measurements of discharge from each relief well maintained? If so, indicate total discharge and maximum discharge observed from a single well on the date of inspection.

B-1.11 Abutment Contacts

1.11.1 Any presence of leaks, springs or wet spots near the abutment?


149

1.11.2

Any presence of cracking, settlement or upheaval of earthwork?

1.11.3

Any evidence of erosion or slope instability?

1.11.4

Trees or profuse growth of weeds/bushes?

1.11.5

Any degradation to up/downstream slope protection (rip-rap, turfing)?


C Dam and Dam Block/Reach (Concrete/Masonry) 1.1 General Condition

1.1.1

Any major alterations or changes to the dam since the last inspection?

1.1.2

Is there any new nearby development in the downstream floodplain?

1.1.3

Any misalignment of poles, fencing or walls due to dam movement?

C1.2 Upstream Face Evidence of surface

1.2.1 defects(honeycombbing, staining, stratification)? Concrete/masonry

1.2.2 deterioration (spalling, leaching,

disintegration)? Is cracking present

1.2.3 (structural, thermal, along joints)?

Evidence of differential

1.2.4 settlement (displaced/offset/open

joints)? Presence of vegetation

1.2.5 (growth in joints between blocks)?

Evidence of any other 1.2.6 damage to joints and/or

water stops?


150


C1.3 Crest of Dam

1.3.1

Evidence of differential settlement (displaced/offset/open joints)?

1.3.2

Presence of cracking (structural, thermal, along joints)?

1.3.3

Profuse growth of weeds/grass/plants at any location?

1.3.4 Any degradation to access road?

1.3.5

Any degradation to upstream parapet or downstream curb wall?


C1.4 Downstream Face Evidence of surface

1.4.1 defects (honeycombing, staining,

stratification)?

1.4.2 Concrete/masonry

deterioration (spalling,


151

leaching, disintegration)?

1.4.3


1.4.4

Evidence of differential settlement (displaced/offset/open joints)?

1.4.5

1.4.6

Presence of vegetation (growth in joints between blocks)? Evidence of any other damage to joints and/or water stops?

1.4.7

Excessive seepage/sweating at any location on downstream face?

1.4.8

Significant leakage at any location on downstream face?


C1.5 Abutment Contacts

1.5.1 Any presence of leaks, springs or wet spots in vicinity of abutment?

1.5.2 Any presence of cracking or settlement?

1.5.3

Profuse growth of weeds/grass/plants at any location?


D Gallery/Shaft and Drainage D-1.1 General Condition

1.1.1

Slushy condition or water logging immediately downstream of dam?

1.1.2

Any evidence of boiling in vicinity of dam toe?

D-1.2 Gallery/Shaft Condition

1.2.1

Any problems accessing or inspecting gallery/shaft (obstruction)?


152

1.2.2 Any safety issues (inadequate handrails,

lighting or ventilation)?

Problems of inadequate drainage

1.2.3 (slippery stairs, water logging of gallery,

clogged porous or foundation drains)? Evidence of

1.2.4 differential settlement (displaced/offset/open

joints)? Excessive

1.2.5 seepage/sweating at any location along

gallery/shaft? Significant or excessive leakage at any location

1.2.6 along gallery/shaft / porous drain? If yes, provide location(s). Are proper arrangements made for

1.2.7 the measurement of seepage into the

gallery? Is the seepage measured separately

1.2.8 from Porous pipes, Foundation drains and Monolith Joints? Are the above

1.2.9. arrangements satisfactory?

Has there been substantial progressive reduction in the seepage through the

1.2.10. foundations? Indicate if it is due to choking

of the drain holes and if so, indicate the number of choked holes. Are all the foundation and porous holes periodically cleaned with reaming tool and

1.2.11. air water jetting? Indicate the last date of


153

such cleaning and extent of variation observed in the seepage discharge

before and after the cleaning.

1.2.12

Is the seepage water and the deposit, if any, from the seepage being regularly examined for chemical composition? If so, indicate the result and the probable source of dissolved salts, if any.

1.2.13.

Are any seepage water springs observed in the downstream area any where? If so, indicate the locations and state the physical nature of this seepage. Look out for such seepage spots particularly near the dykes, fault zone etc. Ascertain if chemical testings are made of water samples from such springs for dissolved salts.

1.2.14

Is there any leachate deposition? If yes provide location


D-1.3 Drain Condition

1.3.1 Is the flow in thedrain unusually high orlow?

1.3.2

Presence of calcium or other deposits in drain?

1.3.3

Is the dewatering pumping station fully operational?

1.3.4 Any problem inspecting the pump?

1.3.5

Any obstruction preventing or impairing smooth operation?


154

1.3.6

Any deterioration of pump and associated equipment?

1.3.7 Is the sump well clean and maintained?

1.3.8

Is the V-notch before sump well cleaned and maintained?

1.3.9

1.3.10

Any other evidence of the drain being blocked/having reduced section? Is the flow in the drain noticeably sporadic/irregular?

1.3.11

Does the drainage water have unusual color (leachate)?


D-1.4 Body Wall (Masonry/Concrete) of ‘NOF’Dam

1.4.1

What is the total seepage into gallery from the porous pipes in the dam at lake full condition? Compare it with the seepage when the reservoir was first filled. (For the corresponding water level)

1.4.2

Has there been substantial reduction in this seepage? Ascertain and indicate the probable reasons therefore.

1.4.3

Has there been a tendency for gradual reduction of drainage through pipes and progressive appearance of sweating on the downstream face of the dam?

1.4.4

Has there been considerable leaching from the seepage water and deposition of lime near the seepage exit spots?


155

1.4.5

Are the samples of the seepage water and reservoir water being regularly tested for reactive and corrosive properties?

1.4.6

1.4.7

Is there excessive seepage, sweating at any locations on the downstream face of the dam? ( Examine the monolith or construction joints for such seepage and leaching and indicate the findings) Is there any swelling or cracking observed on the downstream face especially near the points of concentration of stresses like the toe or locations of abrupt change in geometry of the face of the opening? If so, indicate the details of observations.

1.4.8

Is the pointing on upstream face of the dam in good condition? If not, indicate the nature and extent of deficiency.

1.4.9

Are the registers and graphs showing the periodical measurements of seepage discharge from the porous drains in the gallery and from the downstream face at various lakelevels maintained at site?

E Spillway and Energy Dissipation Structure

E 1.1 Spillway

1.1.1

Any problems inspecting spillway (obstructedaccess, damagedcatwalk)?


156

1.1.2

Any obstructions in or immediately downstream of the spillway?

1.1.3

Evidence of abrasion, cavitation or scour on glacis (e.g. exposed reinforcement)?

1.1.4 Presence of displaced, offset or open joints?

1.1.5


1.1.6

Evidence of surface defects (honeycombing, staining, stratification)?

1.1.7

Concrete/masonry deterioration (spalling, leaching, disintegration)?

1.1.8

Presence of vegetation (growth in joints between blocks)?

1.1.9

Evidence of any other damage to joints and/or waterstops?

1.1.10

Excessive seepage/sweating at any location on spillway glacis?

1.1.11

Significant leakage at any location on spillway glacis?


E 1.2 Waste Weir Bar and Tail Channel


157

1.2.1

Is the Concrete/masonry spillway bar in good condition? Indicate if there is any leakage through the masonry or from the foundation. If so, what remedial measures are proposed/taken for minimizing the leakage? Is the record of leakage measurement maintained? What is the quantity of Seepage/Leakage on the date of inspection?

1.2.2

1.2.3

Is the coping over the spillway bar in good condition? Does the upstream and downstream faceof waste weir barneed

pointing?

1.2.4

Is there any scouring on downstream side of the bar and/or EDA? If so what remedial measures are proposed/taken?

1.2.5

Are there any damages or undermining to guide walls, divide wall and other appurtenants? If so, indicate what remedial measures are proposed/taken.

E 1.3 Structural performance of the ‘NOF’ and ‘OF’ Portions of Dam Foundations

1.3.1

Are there any signs of structural distress noticed in the dam spillway and foundations in the form of-

i. Excessive deflection with respect to permissible deflection at the time of design


158

ii. Tendency of gradual sliding

iii. Cracking and upheaval or settlement in any part of thebody wall or foundations,

iv. Excessive uplift,

v. Excessive seepage and leaching through the body of the dam and the foundation.

1.3.2

Conspicuous weathering of materials or components in any portion of the body wall or the foundations.

E-1.4 Energy Dissipation Structure

1.4.1 Any problems inspecting energy dissipation structure?

1.4.2 Any obstructions in or immediately

downstream of dissipation structure?

1.4.3

Evidence of abrasion, cavitation or scouron dissipationstructure?

1.4.4 Presence of displaced, offset or open joints?

1.4.5


1.4.6

Evidence of surface defects (honeycombing, staining, stratification)?

1.4.7

Concrete/masonry deterioration (spalling, leaching, disintegration)?

1.4.8

Presence of vegetation (growth in joints between blocks)?

1.4.9 Evidence of any other damage to joints?

1.4.10

Any problems with under-drainage (blockage of open drain holes)?

August 2020

1.4.11

Can the tail pond be drained easily for inspection of the stilling basin or bucket? If not, indicate the alternatives available for dewatering. Please ascertain and indicate the last event of inspection of stilling basin (orbucket).

1.4.12

From the examination of the levels and contour plans and reference marks in tail channel; is there progressive erosion and retrogression in the tail channel? If so, indicate the extent and location of such erosion with reference to the various

components of dam, spillway, outlet, power house etc.

1.4.13

Is the concrete surface of the stilling basin and apron (or bucket) in good condition?

1.4.14

Are there any indications of pitting, cracking, spalling or wearing of the surface of bedding concrete? If so, please give details of the nature and extent of the damage.


bucket? If not, indicate

Is the concrete surface of the stilling basin and

If

Malampuzha Dam

159


160

1.4.15

Is thereany indication of abrasion and cavitation damage (pitting of concrete) especially at friction blocks , chute blocks and slotted roller teeth, the surface near the lower tangent point and the end sill? If so, please give the details of nature and extent of damage.

1.4.16

Is the under drainage of the stilling basin (or bucket) satisfactory? Are all the open drain holes clear and functioning well?

Y

1.4.17 Any other issues? N

G-1.5 Walls: Guide walls/Divide walls/Junction walls/Return walls/Spray walls etc.

1.5.1

Are all the locations of such wall accessible for inspection, maintenance and repairs?

1.5.2

Is the drainage of back sides of the walls (wherever applicable) from the weep holes satisfactory? If not, indicate the nature of deficiencies.

1.5.3

Is there any tendency for the water to undercut the ends of the walls?

1.5.4

Is there any foundation erosion or scour noticed in the vicinity of such walls? If so, give the details of nature and extent of such damage.

1.5.5

Is there any surface erosion/damage caused, to face or body of such walls?


161

1.5.6

Do any of the walls show symptoms of unusual settlement, developments of cracks and tilting? If so, give details of the defects noticed.

1.5.7

Is there any damage to guide bunds? If so, give details of the damage.

G-1.6 EndWeir

1.6.1 Is it accessible?

1.6.2

Is there any erosion, pitting or spalling of the concrete or masonry surface? If so, give details

1.6.3

Is there any scour noticed on the immediate downstream of such weir? If so, give details of location and extent of such damage.

G-1.7 Hydraulic Performance of Energy Dissipation Arrangements

1.7.1

Do the flow conditions in the stilling basin (or bucket) have a tendency to draw material into the bucket and cause its churning and abrasion damage to the surface of bucketsbaffle blocks, apron and end


162

sill?

1.7.2

Is the hydraulic performance in agreement with the results of model studies? (wherever applicable)

1.7.3

Ascertain the performance from observed tail water rating curves and deficient observation, if any, such as sweep outs and excessive erosion under plunge pools and locations of secondary rollers and retrogression.

F Intake/Outlet and Water Conveyance Structure F-1.1 Intake/Outlet Structure

1.1.1

Any problems inspecting intake/outlet structure (obstructed/unsafe access)?

1.1.2

Any obstructions in, upstream or downstream of intake/outlet structure?

1.1.3

Evidence of abrasion, cavitation or scour on intake/outlet structure?

1.1.4

Any evidence of structural distress (displaced/offset/open joints, cracking)?

1.1.5

Any evidence of surface defects and/or concrete/masonry deterioration?


F-1.2 Water Conveyance Structure


163

1.2.1

Any problems inspecting intake/outlet structure (obstructed/unsafe

access)?

1.2.2

Any obstructions in, upstream or downstream ofwater conveyancestructure?

1.2.3

Evidence of abrasion, cavitation or scour on structure?

1.2.4

Any evidence of structural distress (displaced/offset/open joints, cracking)?

1.2.5

Any evidence of surface defectsand/or materialdeterioration?

1.2.6

Any evidence of seepage or leakage from water conveyance structure?


G-1 Hydro-Mechanical Component and Pump G-1.1 Spillway Gates (Radial gates, Vertical lift gates, Automatic gates)

1.1.1

Any problems inspecting gate/Stop- logs (obstructed/unsafe access)?

1.1.2

Is the condition of the steel surface and the surface paint deteriorated?

1.1.3

Are any connection bolts of rubber seals loosened or damaged? If so, indicatethe details ofdefects.

1.1.4

Do any of the rubber seals show signs of weathering, hardening, cracking or tearing and damage?


164

1.1.5

Are the rubber seals of side and bottom touching uniformly all along the sealing surface?

1.1.6

Do the rollers (wherever applicable) touch the track plates uniformly? Are the

1.1.7

rollers well lubricated?

Are the embeded parts of spillway gates, emergency gates and stop-logs in sound condition and free from corrosion, uneven wear, cracking, chipping and dents? If not, state the nature of defects or deficiencies and observation, ifany, regarding suchdefects.

1.1.8

Are the following members and welded, bolted and riveted connections structually sound? If not, please give details of any uneven wear, uneven bearing, cracking, chipping and dents and indicate the findings: (1) Gate leaf and stiffeners

(2) End arms

(3) Trunnion girders / Yoke girder

(4) Stoplogs

(5) Lifting beams

(6) Gantrycranes

(7) Tracks

(8) Trunnion bracket

(9) Chains/wire ropes

(10) Bridgestructure


165

1.1.9

Are the trunnion bearings of radial gates properly lubricated?

1.1.10

Is there any damage or wear caused to the seal plates? If so, indicate the nature of damage noticed.

1.1.11

Are any of the mechanical or structural components and fastners or seals

subjected to excessive wear? If so, please give details.

1.1.12

Is there any tendency for recurring damage to any particular component? Ifso, please givedetails.

1.1.13

Is sufficient stock of spares which need frequentreplacement maintained at thesite?

1.1.14

Any issues with storage of equipment (emergency stop logs, lifting beam and gate leaves)?

1.1.15

Any deterioration, corrosion? scaling? pitting? or cracking? of equipment (connecting bolts, welds?)

1.1.16

Any obstructions preventing or impairing smooth operation?

1.1.17

Any problems with the rollers (not touching tracks, inadequate lubrification)?

1.1.18 Any debris, etc., in the gate grooves?

1.1.19

Any damages to Radial Gate trunion pins?gate arms? lubrication?etc.?

1.1.20

Any damage to embedded parts above waterline? access structure?


166

1.1.21 Any damage to concrete grooves?

1.1.22

Is the staff posted at the site for maintenance and operation of gates, hoists, equipments and electrical installations, well experienced, fully trained and conversant with the job requirements and responsibilities?

1.1.23

Are the following documents maintained at the respective location of all the units?

(1) Maintenance schedules specifying each operation, its frequency and ‘due’ and’ done’ dates.

(2) Operating instructions with ‘dos’ and ‘don’t’ forall operationalunits.

1.1.24

Are the trunnion hub and the brackets well maintained?

1.1.25

Are the trunnions likely to get submerged during actual working of the spillway? if so, ascertain the causes for the same and specify. Please enquire for occurrence of such events, if any.

1.1.26

Are all the nuts of connecting bolts and anchorages properly tightened?


G-1.2 Hoists, Cranes and Operating Mechanisms

1.2.1 Are the hoists working satisfactorily?


167

1.2.2

Any problems inspecting hoist/crane/operating mechanism?

1.2.3

Is sufficient stock of spares which need frequentreplacement maintained at thesite?

1.2.4

Is the full length of the chains or wire rope of the hoist in sound condition and free from broken strands?

1.2.5 Is the electrical wiring in sound condition?

1.2.6 Is the alternative power system for gate

operation working properly?

1.2.7

Is the alternate hand operation system of hoist working properly?

1.2.8

Any deterioration of equipment (connecting bolts, welds, surface, paint work?)

1.2.9

Any wear or damage to wire cables and other moving parts?

1.2.10


1.2.11

Any health and safety concerns (e.g. lack of "danger" sign during maintenance)?


G 1.3. Spillway Bridge, Hoist Bridge, Trunnion Level Bridge Catwalks

1.3.1

Are the decking, girders and structural supports of spillway bridge, hoist bridge, trunnion level bridge and catwalks structurally sound?


168

1.3.2

Is the chequered platform of the bridge structurally sound and safe?

1.3.3

Is there satisfactory arrangement to prevent unauthorized entry into the control structures and bridges?

1.3.4

Are the structural members and joints sound and free from corrosion?

1.3.5

When were the steel components painted last?

1.3.6

Is the surface of steel work and paints satisfactory?

1.3.7 Is the parapet or railing over the bridges

sound, safe and painted?

1.3.8

Is the walkway properly anchored to the piers?

1.3.9

Are the track rails for gantry cranes structurally sound and intact?

G-1.4 Valves

1.4.1 Any problems inspecting valve?

1.4.2


1.4.3

Any deterioration of valve and associated equipment?


G-1.8 Trash Racks

1.5.1 Is the trash rack fixed or movable?

1.5.2

What is the mode of cleaning? Is it manual or by TRCM?

1.5.3

Is the welding work on Trash Rack in sound health?


169

1.5.4 Any problems inspecting trash rack?

1.5.5

Problems of excessive debris and/or inadequate cleaning?

1.5.6

Any deterioration of trash rack (rust, corrosion, and damaged blades)?


G-1.9 Trash Rack Cleaning Machines

1.6.1 Any problems inspecting trash rack cleaning machine?

1.6.2

Missing or inadequate spare parts (particularly requiring regular replacement)?

1.6.3

Any deterioration of equipment (wheel trolleys, gantry structures, operating mechanism, connecting bolts, welds, surface, paint work?)

1.6.4

Any wear or damage to wire cables and other moving parts?

1.6.5


1.6.6

Missing or inadequate provision of back- up/standby power supply?

1.6.7

Any health and safety concerns (e.g. lack of "danger" sign during maintenance)?


G-1.10 Pumps

1.7.1 Any problems inspecting pump?

1.7.2



170

1.7.3

Any deterioration of pump and associated equipment?


G-1.11 Approach bridge, operation platform and cabin (for outlets):

1.8.1

Are the decking, girders and structural supports of approach bridge structurally sound?

1.8.2

Is the floor of the operating platform structurally sound and safe?

1.8.3

Is there satisfactory arrangement to prevent unauthorized entry into the control structures of the outlet?

1.8.4

Are the structural members and joints sound and free from corrosion?

1.8.5

When were the steel components painted last?

1.8.6

Is the surface of steel work and paint satisfactory?

1.8.7

Is the parapet or railing over the control tower, operating platform and approach bridgesound and safe?

G-1.12 Outlet

1.9.1 Is the air vent periodically cleaned?

1.9.2

Are there any structural damages to the intake well?

1.9.3

Is there any leakage observed through the well proper and the conduit concrete or masonry? If so, give details of its location and extent.


171

1.9.4

Is there any damage noticed to the conduit concrete, breast wall and gate slots?

1.9.5

Is the bye-pass valve/filling-in-valve (wherever provided) operating satisfactory?

Take operation trials of the following as provided and record the observations and defects noticed, if any.

(1) Service gate(s).

(2)Emergency gate(s).

(3) Stop-log gate(s).

(4) Sluice valves.

Note- (i) The operating trial

for the emergency gate shall be taken with service gate in partially open position to test the capability of emergency gate for self-closing under these conditions. The trial for the operation of the emergency gate under balanced condition of water pressure also needsto be taken

(ii) To guard against the possibility of outlet gate hoist being operated forcibly after closed position of gate a “Distinctive Mark” should be insisted or check the functioning of the limit switches.

1.9.6

Are there vibrations and noise noticed in operation of outlet gates at any time? If so, please indicate if periodical observations have been taken to ascertain their severity.


172

1.9.7

Is the energy dissipation arrangement working satisfactorily for all the discharges?

1.9.8

Is there any structural damage to the energy dissipation structure? If so, give details of nature and extent of damage.

1.9.9

Is the conduit structurally sound and reasonably leak proof? If not, give details of nature and extent of the defects.

1.9.10

Is there any seepage noticed around the conduit as ascertained from the observations of the downstream

conditions? If so, please indicate if it is likely to cause erosion and piping (In case of earth dams).

G-1.13 Outlet Gates

1.10.1 Is the surface of gates and thepaint deteriorated?

1.10.2

Are the connecting bolts of rubber seals properly tightened or damaged?

1.10.3

Do the rubber seals show signs of weathering and damage and need replacements?

1.10.4

Are the rubber seals of sides and bottom touching the bearing surface uniformly?

1.10.5 Do all the rollers touch the track plates?

1.10.6 Are the rollers well lubricated?

1.10.7

Are the stem rods for lifting the gates perfectly straight?


173

1.10.8 Is the operation of outlet gates smooth?

1.10.9

Are the actual operations of lifting and lowering of the gates and hoist mechanisms adequate and smooth?

1.10.1 0

Are all the gears and hoist mechanisms well lubricated?

1.10.1

1

Is the storing arrangement for emergency gate leaves and the stop logs in satisfactory condition?

1.10.1 2

Are the seal plates/seats in sound condition?

1.10.1

3

Is the full length of wire rope (wherever applicable) of the hoist in serviceable

condition and free from any broken strands?

1.10.1

4

Are all the nuts of connecting bolt and anchors properly tightened?

1.10.1

5

Are all the lifting beams in proper working order and in levelled condition? If not, ascertain the nature and extent of problems.

1.10.1 6

Do any of the mechanical or structural parts of the gate, fasteners of hoist show signs of excessive wear? If so, please give details.

1.10.1 7

Is there any tendency for recurring damage to any particular component or components? If so, please give details.


174

1.10.1

8

Is sufficient stock of spares, which need frequentreplacement, maintained at thesite?

G-1.14 River Outlet/RiverSluice

1.11.1

Is the overall condition of river outlet works/river sluices satisfactory?

1.11.2

Is the operation of the gate (Service/Emergency/S top-log) satisfactory as ascertained by taking operating trial? If not, indicate the defects noticed.

1.11.3

Are the trash racks (wherever provided) cleaned before monsoon?

1.11.4

Is there excessive silting on the upstream of the sluice?

1.11.5 When were the gates last opened for

desilting, etc.?

1.11.6

Please indicate the approximate quantity of the leakage through the gates, if any.

1.11.7

Is there any seepage or leakage through the conduit surface?

1.11.8

Is there any damage to the upstream and downstream convergence of the conduit?

1.11.9

Is the condition of energy dissipation arrangement satisfactory? If not, indicate nature and extent of damage.


175

1.11.1 0

Is there any retrogression noticed in the downstream channel? If so, give details of nature and extent of damage.

H-1 Access Road H-1.1 General Condition

1.1.1

Any problems ensuring security of dam site (including gates and fencing)?

1.1.2

Is there a properly constructed and well maintained all weather access road to thedam site?

1.1.3

What is the type of the pavement of theaccess road and its condition?

1.1.4

Are there properly constructed and well maintained access road arrangements to the following components for inspection, maintenance and repairs? Top of Dam Spillway Gates and hoisting arrangement Drainage gallery, adits

and exits Bridge structure Downstream stilling basin Junction and abutments Outet control tower Outlet gates Toe of earth dam, downstream drainage arrangements and berms. Allsaddle dams.

1.1.5

Are all the masonry structures on various access roads in good condition?

1.1.6

Are all the structures on the access roads adequately safe for allowing passage of plant machineryfor emergent repairs?


176

1.1.7

Any obstructions along or at entrance to access road (temporary or long-term)?

1.1.8

Any slope stability issues (road embankment or adjacent slopes)?

1.1.9

Profuse growth of weeds/grass on or in vicinity of accessroad?

1.1.10

Any drainage problems (standing water on or adjacent to road)?

1.1.11

Any other degradation to road surface (ruts, potholes, cavities, cracking)?


I-1 Instrumentation I-1.1 General Condition

1.1.1

Are all the instruments installed accessible? (Attach separate list).

1.1.2

Are all the locations properly lighted, ventilated and adequately protected from possibilities of damage?

1.1.3

Any problems inspecting instrument (obstructed/unsafe access)?

1.1.4

Is the instrument vulnerable to damage or theft(inadequate protection)?

1.1.5

Any problems ensuring correct functioning of instrument(lighting, ventilation)?

1.1.6

Any evidence of degradation to condition of instrument (rusting, vandalism)?


177

1.1.7

Are all the instruments in working order? Ascertain the cases of instruments going out of order and indicate.

1.1.8

Are all the registers of observations posted up-to-date? Please take test observations and initial the register.

1.1.9

Are all the plotting of the instrumentation data completedup-to- date?

1.1.10

Are sufficient stocks of spares, gauges, master gauges, stationary items etc., maintained at the site for uninterrupteddata collection?

1.1.11 Operator or public safety issues?


I-1.2 CommunicationFacilities

1.2.1

Are following facilities available at dam site? (1) Wireless Telephone / mobile/Fax/Internet

1.2.2

Any other issue (please indicate part, location, etc., as necessary)

K-1 Emergency Preparedness K-1.1. Emergency Action Plan

1.1.1

Is the Emergency Action Plan (EAP) prepared for the dam as per the national guidelines? If not, the expected date of preparation of guidelines

1.1.2 When EAP was last updated?

1.1.3

If not, are any dam staff unaware or insufficiently conversant with the EAP?


178

1.1.4

Any concerned authorities unaware or insufficiently conversant with the EAP?

1.1.5

Are communication directories/contact details and other dynamic information are being updated annually?

1.1.6

Any problems accessing or operating thecommunication/ warning system?

1.1.7

Are inundation maps updated and available to concerned authorities?

1.1.8

Are the concerned authorities informed about the system of emergency reporting procedures and warning?

1.1.9

1.1.10

Are available safety spots on the downstream of the dam identified and made known to the concerned authorities? Are adequate warning devices and facilities provided at the dam?

1.1.11

Are proper arrangements made for security of the dam and preventing cases

of unauthorized trespass, vandalism and sabotage tothe dam works?

1.1.12

Date of last annual stakeholder consultation meeting along with mockdrill exercise conducted

1.1.13

Has the EAP been disseminated to all the concerned stakeholders?


179


K-1.2 Inspection of Records

1.2.1

Have the following Dam Safety Documents been prepared and approved by the competent authority?

I. As Built Drawings II. EAP

III. Completion Report

IV. Data Book

V. O and Mmanual

1.2.2

Are the relevant documents reviewed and updated from time to time?

1.2.3

Are all the members of the maintenance staff adequately trained and fully conversant with their responsibilities concerning.

(a) Designer’s Operation Criteria.

(b) Standing Operating Procedures.

(c) Maintenance and Vigilance Procedures of the dam.

(d) Maintenance and operation of allcontrol equipments.

(e) Reservoir Operation Schedules,

Gate Operation Schedule

(f) Maintenance and Operation of all instruments.

(g) Identification of signs of deficient behavior.

(h) Reporting Procedures of emergency situations.


180

(i) Emergency repairs

L-1.1 Inspection Photographs

1.1.1 Information to be furnished as per Annexure - II


181

Annexure 5 1. RESERVOIR OPERATIONRULES

Operation rules ensure that irrigation releases will match the water allocation for the scheme. The rules concern the start and the closure of the irrigation season. Starting storage and the irrigation supplies. Rules for the regulation and distribution of water for Malampuzha project have been framed in 1974 and present operation system for different crops are in turns of seven days of duration inrotation.

1. If the reservoir level on the 1st October is 112.70 m or more. Canal sluices will be opened on 20th October for second crop and the entire command will be fed for whole crop period also third crop release will be made from thereservoir.

2. If the reservoir level on the 1st October is between 111.40 and 112.70 m. canal sluice will be opened on 20th October. But the third crop release will be confirmed reviewing the storage position on January1st

3. If the reservoir level on the 1st October is below 111.40 m no third crop release will be made from thereservoir.

4. If the reservoir level on the 1st January is 107.60 m and above canal sluices will be opened on 10th February for third crop. If it is below 105.60 m on 1st January no supplementation will be made for the first cropalso.

The closure of the season depends on the crop pattern adopted. In paddy based schemes like these releases are stopped 15 days prior to the date of last harvest. The rules should cover adjustments in irrigation release schedules in case of emergencies such as excessive rain or floods and breaches incanal. 2. RESERVOIR OPERATIONTABLE

Based on the past few years’ performance and as proposed in the new operation strategies a typical reservoir operation table has been prepared. The inflow details for the past ten years(1984 -1994 ) has been taken for typical reservoir operation plan. Rainfall details for the last 23 years also available(1972-1995).

3. CROPPING CALENDAR ANDSCHEDULE

First crop is mainly rain fed from May to September. It has been scheduled to supply water for the land preparation and transplantation. Second crop starts from 20th October to 31st January. In the proposed rules releases for third crop is scheduled for a command of 15000 Ha. The second crop is fully dependent on the supply from the reservoir. Maximum water requirements are found to be in the month of December and January. Releases for the full season in seven days turn are scheduled. High yielding medium duration paddy for second crop are proposed. Paddy irrigation needs continues supply of water or with short irrigation intervals. Irrigation intervals are normally prescribed by the Agricultural department. An ON/OFF system is scheduled for second crop. The schedules are only target schedules. The release during the season may change due to variation in water availability. CWR arrived using Modified Permanent Method ad by taking into account of the seepage and percolation losses. Individual field irrigation using farm and field channels provides scope for more effective use of rainfall in paddy fields and reduces field losses. But field to the field irrigation is practiced now. Water supply to fields should be ensured by the farmers during the critical period of growth. In major schemes staggering of starting duties isusually


182

assumed at the design stage of the project to avoid very high peaks in the irrigation requirements.

4. OPERATIONPLAN

Detailed operation plan has been prepared and submitted to the Project Advisory Committee of the farmers’ representative and Agricultural officers in advance. The approved plan of operation is being carried out during the period of implementation of the scheme which is successful in assuming predictable distribution. Depending upon the varying conditional of the reservoir and also on the climate conditions seasonal operation plan are prepared. It will not be practicable to click to a common operation plan. Time to time changes in the operation plan notified well in advance will enable the farmer utilize the reservoir equitably as predicted. Once there is assured water the reliability can be ensured and the objectives effectively achieved. Once the operation plan is approved it is to be published through the media for publicity for making the farmers aware of the cropping strategies of the year. Carry-over storage could be an ideal solution to overcome water scarcities. Project designed for conjunctive use of surface and ground water could be another solution to mitigate the scarcity. In the absence of such above alternatives, adaptive irrigation to match the available supplies are the only practical option possible to manage the scarcityconditions.

MALAMPUZHA DAM OPERATION TABLE(EXISTING)

Month

Beginning Storage

Mm3

InflowMm3

Release Mm3

Palakkad water supply Mm3

Tank loses Mm3

Total Mm3

End

Storage Mm3

OCTOBER 184.376 19.939 - 0.78 2.55 3.33 200.99

NOVEMBER 200.985 9.185 50.63 0.78 2.63 54.04 156.13

DECEMBER 156.13 - 52.31 0.78 1.95 55.04 101.09

JANUARY 101.09 - 52.31 0.78 1.26 54.35 46.74

FEBRUARY 46.74 - - 0.78 0.58 1.36 45.38

MARCH 45.38 - - 0.78 0.57 1.35 44.03

APRIL 44.03 - - 0.78 0.55 1.33 42.70

MAY 42.7 0.995 - 0.78 0.55 1.33 42.37

JUNE 42.37 23.141 - 0.78 0.82 1.60 63.91

JULY 63.91 49.33 - 0.78 1.42 2.20 111.04

AUGUST 111.04 48.78 - 0.78 2 2.78 157.04

SEPTEMBER 157.04 20.635 - 0.78 2.22 3.00 174.68

MALAMPUZHA DAM RESERVOIR OPERATION SCHEDULE(EXISTING)

Date Quantity

Mm3

Level Month &

date Quantity

Mm3

Level

01-10-1995 184.38 113.38 31-10-1995 200.99 114.50

01-11-1995 200.99 114.15 30-11-1995 156.13 111.96

01-12-1995 156.13 111.96 31-12-1995 101.09 108.78

01-01-1996 101.09 108.78 31-01-1996 46.74 104.35

01-02-1996 46.74 104.35 29-02-1996 45.38 104.31


183

01-03-1996 45.38 104.31 31-03-1996 44.03 104.08

01-04-1996 44.03 104.08 30-04-1996 42.70 103.90

01-05-1996 42.70 103.9 31-05-1996 42.37 103.82

01-06-1996 42.37 103.82 30-06-1996 63.91 105.92

01-07-1996 63.91 105.92 31-07-1996 111.04 109.45

01-08-1996 111.04 109.45 31-08-1996 157.04 112.05


184

Annexure – 6 -- Latest DSRP Report


185


186


187


188


189


190


191


192


193


194


195


196


197


198


199


200


201


202


203


204


205


206


207

APPENDIX 7 - GLOSSARY Abutment― thatpartofavalleysideagainstwhichadamisconstructed.Rightandleftabutmentsare those on

respective sides of an observer lookingdownstream.

Air-Vent Pipe ― a pipe designed to provide air to the outlet conduit to reduce turbulence during

release of water and safeguard against damages due to cavitation.

Appurtenant Structures ― ancillary features of a dam, such as the outlet, spillway, energy dissipation

arrangement power house, tunnels, etc.

ArchDam ―aconcreteormasonrydamthatiscurvedtotransmitthemajorpartofthewaterpressure to

theabutments.

Auxiliary Spillway (Emergency Spillway)― a secondary spillway designed to operate only during

exceptionally large floods.

Backwater Curve ― the longitudinal profile of the water surface in an open channel where the depthof

flow has been increased by an obstruction, an increase in channel roughness, a decrease in channel

width, or a flattening of the bedslope.

Base Width (Base Thickness) ― the maximum width or thickness of a dam measured horizontally

between upstream and downstream faces and normal (perpendicular) to

the axis of the dam but excluding projections for outlets, etc.

Berm ― a horizontal step or bench in the sloping profile of an embankment dam.

Bulkhead gate ― a gate used either for temporary closure of a channel or conduit to empty it for

inspection or maintenance or for closure against flowing water when the head difference is small, e.g.,

for diversion tunnel closure. Although a bulkhead gate is usually opened and closed under nearly

balanced pressures, it nevertheless may be capable of withstanding a high pressure differential when

in the closed position.

Buttress dam ― a dam consisting of a watertight upstream face supported at intervalson the

downstream side by a series of buttresses.

Cofferdam―atemporarystructureenclosingallorpartofaconstructionareasothatconstructioncan proceed

in a dryarea.

Concrete Lift ― in concrete works the vertical distance between successive horizontal construction

joints.

Conduit Outlet Works ― a closed conduit for conveying discharge through or under a dam for different

project purposes.

Consolidation Grouting (Blanket Grouting)― the injection of grout to consolidate a layer of the

foundation, resulting in greater impermeability, strength, or both.

ConstructionJoint―theinterfacebetweentwosuccessiveplacingorpoursofconcretewhereabond, not

permanent separation, isintended.

Core Wall ― a wall built of impervious material, usually concrete or asphaltic concrete, in the body of

an embankment dam to prevent leakage.

Crest gate (spillway gate) ― a gate on the crest of a spillway to control overflow or reservoir water

level.


208

Crest Length ― the length of the dam at its crest (dam top) top of a dam, including the length of the

spillway, powerhouse, navigation lock, fish pass, etc., where these structures form part of the length

of a dam. If detached from a dam, these structures would not be included.

Crest of dam ― Used to indicate the ―top of dam‖. To avoid confusion to indicate the crest of spillway

and top of dam may be used.

Culvert ― a drain or waterway built under a road, railway, or embankment, usually consisting of a pipe

or covered conduits

Cutoff―animperviousconstructionormaterialwhichreducesseepagethroughthefoundation material.

Cutoff trench ― an excavation later to be filled with impervious material to form a cutoff.

Cutoff wall ― a wall of impervious material (e.g., concrete, asphaltic concrete, steel-sheet piling) built

into the foundation to reduce seepage under the dam.

Dam – any artificial barrier including appurtenant works constructed across rivers or tributaries thereof

with a view to impound or divert water; includes barrage, weir and similar water impounding structures

but does not include water conveyance structures such as canal, aqueduct and navigation channel

and flow regulation structures such as flood embankments, dikes, and guide bunds.

Dam failure – failures in the structures or operation of a dam which may lead to the uncontrolled

release of impounded water resulting in downstream flooding affecting the life and property of the

people.

Dam incident – all problems occurring to a dam that has not degraded into dam failure‘

and including the following:

a) Structural damage to the dam and appurtenant works;

b) Unusual readings of instruments in thedam;

c) Unusual seepage or leakage through the dambody;

d) Change in the seepage or leakageregime;

e) Boiling or artesian conditions noticed below an earthdam;

f) Stoppage or reduction in seepage or leakage from the foundation or body of the dam into any of the

galleries, for dams with suchgalleries;

g) Malfunctioning or inappropriate operation of gates;

h) Occurrence of any flood, the peak of which exceeds the available flood discharge capacity or 70%

of the approved designflood;

i) Occurrence of a flood, which resulted in encroachment on the available freeboard, or the adopted

designfreeboard;

j) Erosion in the near vicinity, up to five hundred meters, downstream of the spillway, waste weir, etc.;

and

k) Any other event that prudence suggests would have a significant unfavourable impact on dam

safety.

Dam inspection – on-site visual examination of all components of dam and its appurtenances by one

or more persons trained in this respect and includes investigation of the non-overflow portion,

spillways, abutments, stilling basin, piers, bridge, downstream toe, drainage galleries, operation o f

mechanical systems (including gates and its components, drive units, cranes), interior of outlet

conduits, instrumentation records, and record-keeping arrangements.


209

Dam owner – the Central Government or a State Government or public sector undertaking or local

authority or company and any or all of such persons or organizations, who own, control, operate or

maintain a specified dam.

Dam safety – the practice of ensuring the integrity and viability of dams such that they do not present

unacceptable risks to the public, property, and the environment. It requires the collective application of

engineering principles and experience, and a philosophy of risk management that recognizes that a

dam is a structure whose safe function is not explicitly determined by its original design and

construction. It also includes all actions taken to identify or predict deficiencies and consequences

related to failure, and to document, publicize, and reduce, eliminate, or remediate to the extent

reasonably possible, any unacceptable risks.

Deadstorage―thestoragethatliesbelowtheinvertofthelowestoutletandthat,therefore,cannot be

withdrawn from thereservoir.

Decommission―Takingadamoutofserviceinanenvironmentallysoundandsafemanner,or converting it

to another purpose.

Design flood ― see spillway design flood.

Design life ― the intended period that the dam will function successfully with only routine maintenance;

determined during design phase.

Diaphragm ― see membrane.

Dike (Levee) ― a long low embankment whose height is usually less than 5 m and whose length is

more than 10 times the maximum height. Usually applied to embankments or structures built to

protect land from flooding. If built of concrete or masonry, the structure is usually referred to as a flood

wall. Also, used to describe embankments hat block areas on a reservoir rim that are lower than the

top of the main dam and that are quite long. In the Mississippi River basin, where the old French word

levee has survived, the term now applies to flood-protecting embankments whose height can average

up to 15 m.

Distress condition – the occurrence or potential development of such conditions in the dam or

appurtenance or its reservoir or reservoir rim, which if left unattended to, may impede the safe

operation of dam for its intended benefits or may pose unacceptable risks to the life and property of

people downstream.

Diversion channel, canal, or tunnel ― a waterway used to divert water from its natural course. These

terms are generally applied to temporary structures such as those designed to bypass water around a

dam site during construction. ―Channel ‘is normally used instead of ―canal‖ when the waterway is

short. Occasionally these terms are applied to permanent structures.

Documentation – all permanent records concerning investigation, design, construction, operation,

performance, maintenance and safety of dams and includes design memorandum, construction

drawings, geological reports, reports of specialized studies simulating structural and hydraulic

response of the dam, changes made in design and drawings, quality control records, emergency

action plan, operation and maintenance manual, instrumentation readings, inspection and testing

reports, operational reports, and dam safety review reports;

Drainage area ― an area that drains naturally to a point on a river.

Drainage layer or blanket ― a layer of permeable material in a dam to relieve pore pressure or to


210

facilitate drainage of fill.

Drawdown ― the lowering of water surface level due to release of water from a reservoir.

Earth dam (Earth fill dam) ― An embankment dam in which more than 50 percent of the total volume

is formed of compacted fine-grained material obtained from a borrow area.

Earthen dam or earth fill dam ― see embankment dam.

Embankment dam (Fill dam) ― any dam constructed of excavated natural materials.

Emergency Action Plan (EAP) ― a plan of action to be taken to reduce the potential for damage to

property and loss of life in the area affected by failure of a dam or other potentially hazardous

practice.

Emergency gate ― a standby or reserve gate which is lowers only for repairing/ servicing of the

service gate.

Emergency spillway ― see spillway.

Face―theexternalsurfaceofastructure,e.g.,thesurfaceofawallofadam. Failure

― the uncontrolled release of water from adam.

Filter (filter zone) ― A band or zone of granular material that is incorporated into a dam and is graded

(either naturally or by selection) to allow seepage to flow across or down the filter without causing the

migration of material from zones adjacent to it.

Fixed wheel gate (fixed-roller gate, fixed-axle gate) ― a gate having wheels or rollers mounted on the

end posts of the gate. The wheels move against rails fixed inside grooves or gate guides.

Flapgate ―agatehingedalongoneedge,usuallyeitherthetoporbottomedge.Examplesofbottom-

hingedflapgatesaretiltinggatesandbellygates,socalledduetotheirshapeincross-section.

Flashboards ― a length of timber, concrete, or steel placed on the crest of a spill way to raise the

retention water level but that may be quickly removed in the event of a flood, either by a tripping

device or by deliberately designed failure of the flash board or itssupports.

Flood gate ― a gate to control flood release from a reservoir.

Flood routing ― the determination of the attenuating effect of storage on a flood passing through a

valley, channel, or reservoir.

Flood surcharge ― the volume or space in a reservoir between the controlled retention water level

(Full Reservoir Level) and the maximum water level. Flood surcharge can not retained in the reservoir

but will flow over the spillway until the controlled retention

water level is reached.

Flood wall ― a concrete wall constructed adjacent to a stream to prevent flooding of property on the

landward side of the wall, normally constructed in lieu of or to supplement a levee where the land

required for levee construction is expensive or not available.

Floodplain ― an area adjoining a body of water or natural stream that has been, or may be, covered

by flood water.

Floodplain management ― a management program to reduce the consequences of flooding, either by

natural runoff or by dam failure, to existing and future properties in a floodplain.

Foundation of dam ― the natural material on which the dam structure is placed.

Freeboard―theverticaldistancebetweenastatedreservoirlevelandthetopofadam.

Normal freeboard is the vertical distance between Full Reservoir Level (FRL) and the top of the dam.


211

Minimum freeboard is the vertical distance between the Maximum Water Level (MWL) and the top of

the dam.

Full Reservoir Level (FRL)/Normal water level ― for a reservoir with un-gated spillway it is thespillway

crest level. For a reservoir, whose outflow is controlled wholly or partly by movable gates, siphons or

other means, it is the maximum level to which water can be stored under normal operating conditions,

exclusive of any provision for floodsurcharge.

Fuse-Plug Spillway ― an auxiliary or emergency spillway comprising a low embankment or a natural

saddle designed to be overtopped and eroded away during a rare and exceptionally large flood.

Gallery ― (a) a passageway within the body of a dam or abutment, hence the terms grouting gallery,

inspectiongalleryanddrainagegallery(b)alongandrathernarrowhall,hencethefollowingtermsfor

apowerplantviz.valvegallery,transformergalleryandbusbargallery.

Gate ― a device in which a leaf or member is moved across the waterway from an external

position to control or stop the flow.

Gravity dam ― a dam constructed of concrete, masonry, or both that relies on its

weight for stability.

Grout cap ― a pad or wall constructed to facilitate pressure grouting of the grout curtain beneath it.

Grout curtain (grout cutoff) ― a barrier produced by injecting grout into a vertical zone, usually narrow

horizontally, in the foundation to reduce seepage under a dam.

Guard gate (guard valve) ― a gate or valve that operates fully open or closed. It may function as a

secondary device for shutting off the flow of water in case the primary closure device becomes

inoperable, but is usually operated under conditions of balanced pressure and no flow.

Hazard Classification ― a system that categorizes dams according to the degree of adverse

incremental consequences of a failure or improper operation of the dam. CWC classifies dam hazards

as low, significant, or high.

Heightabovelowestfoundation ―themaximumheightfromthelowestpointofthegeneralfoundation to the

top of thedam.

Homogeneous earth fill dam ― an embankment dam constructed of similar earth material throughout,

except internal drains or drainage blankets; distinguished from a zoned earth fill dam.

Hydraulic fill dam ― an embankment dam constructed of materials, often dredged, that are conveyed

and placed by suspension in flowing water.

Hydraulic height ― the height to which water rises behind a dam and the difference between the

lowest point in the original streambed at the axis of the dam and the maximum controllable water

surface.

Hydrograph ― a graphic representation of discharge, stage, or other hydraulic property with respectto

time for a point on a stream.(At times the term is applied to the phenomenon the graphic

representation describes; hence a flood hydrograph is the passage of a flood discharge past the

observationpoint.)

Inclinometer ― an instrument, usually consisting of a metal or plastic tube inserted in a drill hole and a

sensitized monitor either lowered into the tube or fixed within it. The monitor measures at different

points the tube‘s inclination to the vertical. By integration, the lateral position at various levels of the

tube may be found relative to a point, usually the top or bottom of the tube, assumed to be fixed. The


212

system may be used to measure settlement.

Intake ― any structure in a reservoir, dam, or river through which water can be drawn into an

aqueduct.

Internal Erosion ― see piping.

Inundation map ― a map delineating the area that would be inundated in case of a failure.

Leakage ― Uncontrolled loss of water by flow through a hole or crack.

Lining ― a coating of asphaltic concrete, reinforced or unreinforced concrete, shotcrete, rubber or

plastic on a canal, tunnel etc. to provide water tightness, prevent erosion, reduce friction, or support

the periphery of structure. May also refer to lining, such as steel or concrete, of outlet pipe or conduit.

Low-level outlet (bottom outlet) ― an opening at a low level from a reservoir generally used for

emptying or for scouring sediment and sometimes for irrigation releases.

Maintenance ― the recurring activities necessary to retain or restore a dam in a safe and functioning

condition, including the management of vegetation, the repair or replacement of failed components,

the prevention or treatment of deterioration, and the repair of damages caused by flooding or

vandalism.

Masonry dam ― a dam constructed mainly of stone, brick, or concrete blocks that may or may not be

joined with mortar. A dam having only a masonry facing should not be referred to as a masonry dam.

Maximum cross-section of dam ― across-section of a dam at the point of its maximum height.

Maximum water level ― the maximum water level, including flood surcharge, the dam is designed to

withstand.

Membrane (Diaphragm) ― a sheet or thin zone or facing made of a flexible material, sometimes

referred to as a diaphragm wall or diaphragm.

Minimum operating level ― the lowest level to which the reservoir is drawn down under normal

operating conditions.

Morning glory spillway ― see spillway.

One-Hundred Year (100-Year) Exceedance Interval ― the flood magnitude expected to be equaled or

exceeded on the average of once in 100 years. It may also be expressed as an exceedance

frequency, i.e. a percent chance of being exceeded in any given year.

Operation―theadministration,management,andperformanceofmaintenanceactivitiesnecessaryto keep

a dam safe and functioning asplanned.

Outlet ― an opening through which water can be freely discharged from a reservoir.

Outlet gate ― a gate controlling the outflow of water from a reservoir.

Overflow dam ― a dam designed to be overtopped.

Parapet Wall ― a solid wall built along the top of a dam for ornament, for the safety of

vehicles and pedestrians, or to prevent overtopping.

Peak Flow ― the maximum instantaneous discharge that occurs during a flood. It coincides

with the peak of a flood hydrograph.

Pervious Zone ― a part of the cross section of an embankment dam comprising material of high

permeability.

Phreatic Surface ― the top most flow line in an embankment dam.

Piezometer ― an instrument for measuring pore water pressure within soil, rock, or concrete.


213

Piping ― the progressive development of internal erosion by seepage, appearing downstream as a

hole or seam discharging water that contains soil particles.

Pore Pressure ― the interstitial pressure of water within a mass of soil, rock, or concrete.

Pressure Cell ― an instrument for measuring pressure within a mass of soil, rock, or concrete or at an

interface between one and the other.

Pressure Relief Pipes ― Pipes used to relieve uplift or pore water pressure in a dam‘s foundation or

structure.

Primary Spillway (Principal Spillway) ― the principal or first-used spillway during flood flows.

Probable Maximum Flood (PMF) ― a flood that would result from the most severe combination of

critical meteorologic and hydrologic conditions possible in the region.

Probable Maximum Precipitation (PMP) ― the maximum amount and duration of precipitation that can

be expected to occur on a drainage basin.

Program ― any authorized activity used to implement and carry out goals, actions, and objectives

contained within the authorizing legislation.

Program Life ― the period in a contract, conservation plan, or plan during which the conservation

practice or conservation system shall be maintained and used for the intended purpose; determined

by programrequirements.

Pumped storage reservoir ― a reservoir filled entirely or mainly with water pumped from outside its

natural drainage area.

Radial gate (Tainter gate) ― a gate with a curved upstream plate and radial arms hinged to piers or

other supporting structures.

Regulating dam ― a dam impounding a reservoir from which water is released to regulate

Rehabilitation ― the completion of all work necessary to extend the service life of the practice or

component and meet applicable safety and performance standards.

Relief well ― vertical wells or boreholes,

constructed downstream of an embankment dam to relieve the pressure from confined pervious

layers in foundation overlaid by an impervious layer to arrestboiling.

Repair ― actions to restore deteriorated, damaged, or failed dam or its component to an acceptable by

meeting functional condition.

Replacement ― the removal of a structure or component and installation of a similar, functional

structure or component.

Reservoir area ― the surface area of a reservoir when filled to controlled retention level.

Reservoir routing ― the computation by which the interrelated effects of the inflow hydrograph,

reservoir storage, and discharge from the reservoir are evaluated.

Reservoir surface ― the surface of a reservoir at any level.

Riprap ― a layer of large stones, broken rock, or precast blocks placed randomly on the upstream

slope of an embankment dam, on a reservoir shore, or on the sides of a channel as a protection

against wave action. Large riprap is sometimes referred to as armoring.

Risk assessment ― as applied to dam safety, the process of identifying the likelihood and

consequences of dam failure to provide the basis for informed decisions on a course of action.

Rock fill dam ― an embankment dam in which more than 50 percent of the total volume comprises


214

compacted or dumped pervious natural or crushed rock.

Rock fill Dam ― see embankment dam.

Roll Crete or Roller-Compacted Concrete - a no-slump concrete that can be hauled in dump trucks,

spread with a bulldozer or grader, and compacted with a vibratory roller.

Rolled fill dam ― an embankment dam of earth or rock in which the material is placed in layers and

compacted using rollers or rolling equipment.

Seepage ― the interstitial movement of water that may take place through a dam, its foundation, or its

abutments.

Service Life ― the actual period after construction of a dam, during which the practice functions

adequately and safely with only routine maintenance; determined by on-site review.

Service/Regulatinggate(regulatingvalve)―agateorvalvethatoperatesunderfullpressureandflow to

throttle and vary the rate ofdischarge.

Shaft Spillway (Morning Glory Spillway) ― a vertical or inclined shaft into which flood water spills and

then is conducted through, under, or around a dam by means of a conduit or tunnel. If the upper part

ofthe shaft is splayed out and terminates in a circular horizontal weir, it is termed a bell mouth‖ or

morning glory‖ spillway.

SideChannelSpillway―aspillwaywhosecrestisroughlyparalleltothechannelimmediately

downstream of thespillway.

Sill ― (a) A submerged structure across a river to control the water level upstream. (b) The crest of a

spillway. (c) A horizontal gate seating, made of wood, stone, concrete or metal at the invert of any

opening or gap in a structure, hence the expressions gate sill and stop log sill.

Siphon Spillway ― a spillway with one or more siphons built at crest level. This type of spillway is

sometimes used for providing automatic surface-level regulation within narrow limits or when

considerable discharge capacity is necessary within a short period.

Slide gate (sluice gate) ― a gate that can be opened or closed by sliding it in supporting

guides.

Slope ― (a) the side of a hill or mountain. (b) The inclined face of a cutting or canal or embankment.

(c) Inclination from the horizontal. In the United States, it is measured as the ratio of the number of

units of horizontal distance to the number of corresponding units of vertical distance. The term is used

in English for any inclination and is expressed as a percentage when the slope is gentle, in which

case the term gradient is alsoused.

SlopeProtection―theprotectionofaslopeagainstwaveactionorerosion.

Sluiceway ― see low-leveloutlet.

Spillway ― a structure over or through which flood flows are discharged. If the flow is controlled by

gates, it is a controlled spillway; if the elevation of the spillway crest is the only control, it is an

uncontrolled spillway.

Spillway Channel (Spillway Tunnel) ― a channel or tunnel conveying water from the spillway to the

river downstream.

Stilling Basin ― a basin constructed to dissipate the energy of fast-flowing water, e.g., from a spillway

or bottom outlet, and to protect the riverbed from erosion.

Stop logs ― large logs or timber or steel beams placed on top of each other with their ends held in


215

guides on each side of a channel or conduit providing a cheaper or easily handled temporary closure

than a bulkhead gate.

Storage ― the retention of water or delay of runoff either by planned operation, as in a reservoir, or by

temporary filling of overflow areas, as in the progression of a flood crest through a natural stream

channel.

Tail water Level ― the level of water in the tailrace at the nearest free surface to the turbine or in the

discharge channel immediately downstream of the dam.

Tailrace ― the tunnel, channel or conduit that conveys the discharge from the turbine to the river,

hence the terms tailrace tunnel and tailrace canal.

Toe of Dam ― the junction of the downstream face of a dam with the ground surface, referred to as

the downstream toe. For an embankment dam the junction of upstream face with ground surface is

called the upstream toe.

Top of Dam ― the elevation of the uppermost surface of a dam, usually a road or walkway, excluding

any parapet wall, railings, etc.

Top Thickness (Top Width) ― the thickness or width of a dam at the level of the top of the dam. In

general, ―thickness‖ is used for gravity and arch dams, ―width‖ for other dams.

Transition Zone (Semi-pervious Zone) ― a part of the cross-section of a zoned embankment dam

comprising material of intermediate size between that of an impervious zone and that of a permeable

zone.

Trash rack ― a screen located at an intake to prevent the ingress of debris.

Tunnel ― a long underground excavation usually having a uniform cross-section. Types of tunnel

include: headrace tunnel, pressure tunnel, collecting tunnel, diversion tunnel, power tunnel, tailrace

tunnel, navigation tunnel, access tunnel, scour tunnel, draw-off tunnel, and spillway tunnel.

Under seepage ― the interstitial movement of water through a foundation.

Uplift ― the upward pressure in the pores of a material (interstitial pressure) or on the base of a

structure.

Upstream Blanket ― an impervious layer placed on the reservoir floor upstream of a dam. In case of

an embankment dam, the blanket may be connected to the impermeable element in a dam.

Upstream Blanket ― see blanket.

Valve ― a device fitted to a pipeline or orifice in which the closure member is either rotated or moved

transversely or longitudinally in the waterway to control or stop the flow.

Water stop ― a strip of metal, rubber or other material used to prevent leakage through jointsbetween

adjacent sections ofconcrete.

Weir― (a)alowdamorwallbuiltacrossastreamtoraisetheupstreamwaterlevel,calledfixed-crest weir

when uncontrolled. (b) A structure built across a stream or channel for measuring flow,

sometimescalledameasuringweirorgaugingweir.Typesofweirincludebroad-crestedweir,sharp-

crested weir, drowned weir, and submergedweir.

Zoned embankment dam ― an embankment dam composed of zones of materials selected for

different degrees of porosity, permeability and density.

Operation and Maintenance Manual for MALAMPUZHA DAM

Documents

Transcript of Operation and Maintenance Manual for MALAMPUZHA DAM