KALABAGH DAM PROJECT

NEED FOR KALA BAGH

Shortage of energy is the most serious handicaprestricting Pakistan's development progress. Despite thetransformation in the energy profile since the birth of thecountry in 1947 the hydro contribution is still less than 17%.

The demand for electricity is growing rapidly and isoutstripping the rate at which new generating capacity can beintroduced.

The position of indigenous natural gas is as gloomy.During the last two decades quite a few gas fired turbines wereinstalled. However, in view of the dwindling reserves in theknown gas fields, the Government of Pakistan had to place a totalban on use of gas for any new power plants.

As the country is deficient in energy resources,Pakistan has been severely affected by the increases in oil pricessince 1973. In view of the concerns regarding the sources andreliability of nuclear fuel supplies, and the negligible provenindigenous reserves of gas and fossil fuels, major emphasis hasbeen placed by the scientists and economists on hydro-powerdevelopment.

The proposed Kalabagh dam project is designed to have apower house, initially, with 8 power units of 300 MW each and willadd over 11,000 GMH of average annual energy to the national grid.

At present only about 36 million acres of thepotentially cultivable Perennial irrigation in the Indus Zone isat present restricted to 52% of the irrigated areas that could beserved, and the utilization of the canals during the low watermonths is at present only around 36%.

Construction of the proposed Kalabagh Project willincrease the total reservoir storage volume in Pakistan by 55%.The present average annual volume of water released at the canalheads below Kalabagh is 72 MAF at the planned pre-Kalabagh stage.Post Kalabagh,this volume will increase to 79 MAF. The regulationmade possible by the reservoir would then increase the utilization

of the existing canals to 44% in the low water months compared tothe present 36%.

BACKGROUND.

The field investigations for the Kalabagh dam projectwere initiated by the Government of Pakistan during 1953. Until1973, the project was basically considered as a storage projectfor meeting irrigation needs. However, the oil crisis of 1973 andthe consequent rapid increase in the cost of energy have greatlyenhanced the priority of Kalabagh as a power project.

The irrigated agriculture system in the Indus plains isthe oldest and the largest irrigation system in the World. Morethan 36 million acres (15 million hectares) are under the commandof 20 barrages and 38000 miles (61000 km)of irrigation canals.Uniquely, however, till recently, this vast system was completelydependent upon unregulated natural river flows without the benefitof any storage reservoirs to regulate the flows. Notwithstandingthe fertile lands and the climate being favorable for cropsthroughout the year, the agriculture output per acres was one ofthe lowest in the world. The most important factor responsible wasthe inadequacy of water supplies to support high intensity modernagriculture. Due to the pronounced seasonality in the riverflows, the shortages occurring during critical periods of sowingand maturing were particularly damaging to the crops. It ispertinent to state here that it was only after completion of theMangla and Terbala reservoirs, that the agricultural output inPakistan brought the country near self sufficiency in food grins.Sind has increased its withdrawls to 22% inspite of their risenobjectives. Given adequate and timely irrigation water suppliesand other inputs, Pakistan with vast and resources can producesufficient surplus food grains for export to other deficitnations. The need to construct storage reservoirs to regulateriver flows was therefore one of the priorities selected byPakistan right from the begging.

EFFORTS OF CONSULTANTS.

The Government engaged M/S Tipton and Hill a ConsultingEngineering firms of USA in 1953. A preliminary feasibilityreport of the Kalabagh dam project was submitted by them in 1956which concluded the technical feasibility and economic viabilityof an embankment type dam 275 feet (84 meters) high creating agross storage capacity of 8 MAF with a powerstation including 6units of 138 MW each. At that time adequate sediment data was notavailable, but the consultants pointed out the need to allow forsluicing sediment through the reservoir.

The World Bank's special study group headed by Dr PieterLieftinck assisted by consulting engineering firms of Chas.T.Main for storage reservoirs, Stone and Webster for power aspectsand IACA for agriculture, completed their report in 1967.

WAPDA with the help of their general consultants, HarzaEngineering Company of USA, continued studies on alternative damaxes in the general vicinity of the Kalabagh gorge.

Associated Consulting Engineers, (ACE) of Pakistan wereengaged by WAPDA in 1972 to carry out the feasibility studies ofthe project.

Feasibility studies, WAPDA had appointed a board ofinternational experts comprising Messers F.F. Snyder, E.M FucikE.S Smith E.J. Beck Dr. D.B. simons Prof. L. Muller and Prof . F.BSlichter (Dr H.A Einstein and Mr. L. Noe also served in earlierstages)who reviewed the studies at different stages. World Bankfour-man mission reviewed the existing data and reports andinspected the dam site.

PROJECT OBJECTIVES.

The proposed Kalabagh dam project is multi-purpose. Itsmain objectives are:-

a. To Generate large amounts of low cost hydroelectricpower near major load centers, and supply the existing grid formeeting the growing power demand of agricultural, industrial anddomestic consumers.

b. To provide additional storage on the Indus and thus reduce the existing system shortfalls in meeting the irrigation requirements.

c. To compensate for the storage, lost due to the siltingup of existing reservoirs till such time that their

substitutes, presently being planned, are actually available.

d. To regulate and control the flood peaks of the Indus to minimize the flood hazards downstream.

e. To increase Pakistan's capacity to manage its water distribution and power generation systems through the conjunctive operation of Tarbela and Kalabagh

reservoirs.

INDUS (RIVER).

The Indus river, the father of all rivers with itstributaries is one of the greatest river systems. Its main steamis (1800 miles) long and its drainage areas is 37200 square miles.

It rises in Tibet with its source about 30 miles northof Mansarowar lake on the northern slopes of Kailas Parbat, 18000feet above sea level. In its upper reaches, it flows westward andnorth-westward for 750 miles through the great Karakoram andHimalayan ranges under the shadow of the world's highest mountainpeaks, fed by the world's largest glaciers on its way. Thenflowing below the famous Nanga parbat (26600 feet) and joiningwith Gilgit river and Astor river, it continues for another 160miles till it debouches in the Tarbela plain where it is joined bythe Siran river.

Below Tarbela after 32 miles it reaches the Attock gorgewhere the Kabul river joins it from the west. Below Attock joinedby the Haro and Soan rivers. From Kalabagh to the sea it flowsfor about 770 miles through extremely flat plains formed by itsown sediment deposits. It receives Punjanad (five river) carryingthe combined flows of the Jhelum, Chenab, Ravi, Beas and Sutlejrivers midway in the plains at Mithankot. The Indus river onentering Pakistan controlled flows at an elevation of about 8,000feet above mean sea level. It drops to an elevation of 680 feetat Kalabagh below which it enters the flat plains of the Punjab.With the total drop of about 7000 feet, it has vast potentialitiesof hydropower. Till now only one project viz the Tarbela dam hasbeen completed on it and the lower most feasible site viz Kalabaghis now planned for implementation.

SITE CONDITIONS.

The Kalabagh dam site, indicated on is located 120miles downstream of Tarbela and 16 miles upstream from the JinnahBarrage. The site is a narrow and deep channel extending over a 5mile distance where the river is about 1300 ft.

Upstream, the Indus flows in a narrow valley from Attock90 miles to the north where the Kabul river joins the Indus . Thetown of Nowshera is located on the Kabul river about 16 milesupstream from its confluence with the Indus.

Both a metalled road and a railway line run along theleft bank of the river about 7 miles. An access road and anairstrip have been constructed. Railway bridge across the riverIndus exists at Kalabagh, about 12 miles downstream of the site.

The catchment area of the River Indus and itstributaries at the site is 110,500 square miles of which thecatchment area of the Kabul at Nowshera is 34,300 square miles andof the Indus at Tarbela is 65500 square miles.

The average flow of the Indus at Kalabagh is 89 MAF peryear based on an analysis of records dating back to 1873. Minimumand maximum annual flows have been recorded as 62 MAF in 1974 and119 MAF in 1959. Recorded mean daily flows have ranged between

the extremes of 9000 cfs in 1975 to 1,025,000 cfs in 1929. Thereis a marked seasonal variation in flows which is characteristic ofthe Indus, with high flows in summer from snow melt and monsoonrains and low flows in winter.

Historical data indicate that moderate to largeearthquakes have occurred within 125 miles of the damsite,although there is no record of large events close to the site.The largest instrumentally recorded even within 125 miles of thesite was the 1955 Leiah earthquake which occurred some 110 milesto the south with a magnitude of 5.6. A seismic evaluation of thesite has been carried out, based on a detailed study of the faultsin the area and available instrumental records.

PROJECT DESCRIPTION.

Governing parameters.

The project designs have been developed to meet the followingprincipal parameters:

a The town of Nowshera should not be inundated by thereservoir. However, the low lying parts of the townaffected by the backwater during high floods should beprotected.

b. The project, being constructed on the main stem of theprimary river in the country, should have adequate low levelrelease capacity to meet future irrigation requirements,taking into account the possible future expansion ofirrigation agriculture in the command area.

c. The project should have structural provisions to becapable of being operated in such a way that significantproportion of the incoming sediment can be passed throughthe reservoirs so as to prolong its life. The long narrowgorge of the Indus limb of the Kalabagh reservoir is a veryfavorable feature conducive to efficient sluicing.

d. The project should be designed to be operated inconjunction with Tarbela and Chashma so as to provideirrigation water, power and flood alleviation, and tomaximize the benefits obtained from the system.

e. The project should be designed to withstand the probablemaximum flood (PMF), which could have a peak inflow of 3,550,000 cfs.

f. The project should be designed to withstand a maximumcredible earthquake (MCE), which could produce a maximumeffective peak horizontal bedrock acceleration, at thedamsite, of 40% of acceleration due to gravity (g), withoutcatastrophes release of water from the reservoir.

g. All elements of the project should be designed withsafety, reliability during operation and ease of maintenanceas prime requirements.

BENEFITS OF KALA BAGH DAM.

1. The proposed methods of operating Kalabagh inconjunction with Tarbela reservoir and other reservoirs in theriver system it to:

a) meet irrigation demands to the greatest perceptible extent.

b) generate electrical power and energy.

c) alleviate flood damage in downstream areas.

2. Reservoir rule curves provide recommended maximum andminimum reservoir water level on a period by period basisthroughout the year. Economic studies have demonstrated that itis preferable to operate the reservoirs to meet irrigation demands

to the greatest possible extent while spreading shortfallsthroughout the year to ensure a reasonable pattern of powergeneration and to avoid acute crop water deficiencies.

It is proposed to draw Kalabagh down to its minimumstart level of 825 ft at the begining of June in most years and tomaintain it at this level for around 50 days to allow accumulatedsediment to be sluiced from the reservoir. Refilling would beaccomplished by the end of September each year.

Since the useful storage volume of the reservoir is onlyabout 8% of the annual flow, the scope for regulation is irrigatedand there is no possibility of over year storage. Nevertheless,as outlined below, this regulation has an important impact on theirrigation water availability downstream of Kalabagh as wellreducing flood risks.

3. Full live storage of 6.1 MAF would be availableguarranteeing assured irrigation supply throughout the yearincluding replacement of storage loss of the three existingreservoirs. It has been estimated that with the construction ofKalabagh project it will be possible to sustain about 79 MAFannually in the irrigation system. Without Kalabagh this figurewould be about 72 MAF. Reservoir operational studies over the1966-79 flow sequence have demonstrated that if Kalabagh were/isnot constructed, the system would experience an average annualshortfall, in water availability against demand, of 6.63 MAF,varying between 3.62 MAF and 12.54 MAF.

With the commissioning of Kalabagh dam, shortfalls willbe completely eliminated in average and above average in flowyears. Some shortages will, however, occur in dry years.The average annual relief will amount to 4.72 MAF varying between2.76 MAF and 7.56 MAF . This will reflect an average improvement

of 71%. The additional water will mostly be made available duringthe Rabi season from October to March, thus increasing thecultivated area which may be cropped twice annually, as well asraising the total cropped acreage, and meeting the future cropwater requirements of the existing area.

As Tarbela reservoir is silting up at a faster rate thanKalabagh. The net improvement in irrigation releases due to thecompensating influence of Kalabagh rises to a maximum of 6.8 MAF.

POWER GENERATION.

The proportions of thermal and hydro power and energygenerated in Pakistan vary throughout the year. Hydro generationis chosen when possible in order to reduce fuel costs, but itsavailability is dependent upon seasonal variations in reservoirlevel, river flows and irrigation release requirements.Kala Baghwill give initial installed capacity of 2400 MW.

When the reservoir is full, Kalabagh will be able to generate3600 MW. During the short period of sluicing in June, when thereservoir is held at maximum level, the generation capability willreduce 1158 MW.

With large amounts of energy (GWh) generated during thesummer months, the station will operate as a source of base loadpower with thermal plant providing additional peak time power asrequired.

During the other months of the year, water releases will belimited to meet irrigation demands, so less energy will begenerated. Some units at Kalabagh will generate base load energywhilst some will be restricted to peak time operation. Thermalplant will then be used to supplement the hydro base energy tosatisfy the load demand pattern.

Kalabagh will generate an average of 11,413, MKWH annuallygiving a plant capacity factor of 53%. The conjunctive operationof Kalabagh and Tarbela would enable average annual energytotalling over 27000 GWh to be generated jointly. 514 GWh of thisarises from the conjunctive operation of the two reservoirs.

5. Flood Alleviation.

Kalabagh dam will reduce the frequency and severity offlooding in downstream areas over the whole 770 river miles to thesea, the alleviation being particularly significant over the 300river miles between the dam and the Indus-Sutlaj confluence.Kalabagh reservoir will be drawn down at the start of the monsoonflood season and will not be refilled until late in the season, sothat most floods will be absorbed by the reservoir or, at theleast significantly abated by it.

6. Sediment control.

The useful storage of reservoirs on the Indus and itstributaries is being seriously depleted due to the deposition inthe reservoirs of large volumes of sediment carried by the rivers.At present Tarbela acts as a trap for a significant proportion ofthe sediment that would otherwise reach to Kalabagh. Once storageat Tarbela is lost, nearly all the average annual sediment load of500 million short tones will pass into Kalabagh.

After detailed study, it has been concluded that the life ofthe reservoir at Kalabagh will be extended by drawing down toreservoir each year and utilizing the high flows to pick up thedeposited sediment and transport it through the reservoir.

Besides increasing the life of the reservoir, sluicing willlimit the build up of deposits near Attock and will thereforelimit the extent to which river bed levels, and the backwaterlevel during high floods in the low laying areas of Nowshera areaffected by the reservoir.

Kalabagh Dam Project would play very important role by way of:-

a) Replacing storage lost by sedimentation in existing reservoirs at Mangla, Chashma and Tarbela (estimated about 3 MAF by the year 2000).

b) Providing additional storage to meet existing-water shortage during early Kharif sowing period of April-June (particularly critical for cotton crop in Sindh.

c) Providing effective regulation of Indus River to meet additional Kharif allocations of the provinces under

WAA,1991.

d) Regulation and control of high flood peaks in the Indus to enable provision of perennial tubewells irrigation to the riverain area in Sindh.

e) Generating a large chunk of hydro-power for meeting the growing demand of agricultural, industrial and domestic consumers through low cost option.

f) Reducing dependence on imported fuels.

g) Creating employment for 30,000 person duringconstruction and significant numbers aftercommissioning.

APPREHENSIONS.

As part of controversy on Kalabagh Dam, a number ofapprehensions/doubts have been expressed by upper(NWFP)and lowerSindh riparian provinces. Most of these are based either on lack

of information or hear say. In addition, there have beenreservations in the mind of some quarters without any apparentrhyme or reason.Consequently, the Project has been thoroughlyreviewed and revised/modified to remove the apprehensions anddoubt, which in the past may have blocked its implementation.

The apprehensions and the factual position, in the lightof critical examination/supporting studies, are presented in thefollowing:-

Apprehensions of NWFP:

i) It is feared that historic flooding of Pashawar Valleyincluding Nowshera town would be aggravated in the event ofrecurrence of 1929 record flood.

ii) Drainage of surrounding area of Mardan, Pabbi and Swabi plains would be adversely affected by the reservoir thus creating water-logging and salinity.

iii) Operation of Mardan SCARP would be adversely affected.

iv) Fertile culturable land would be submerged.

v) Large number of people would be displaced.

Answers:-

1.(a)In the modified design of the project the reservoirconservation level has been lowered by 10 feet from 925 to 915feet above mean sea level (MSL thus eliminating the need forconstruction of any protective dyke near Nowshera. At maximumconservation level of 915 feet,the back water effect of Kalabaghlake would and about 10 miles downstream of Nowshera (referIllustration-I. A state of art computer based study, backed byphysical modelling in Pakistan, has established that recurrence ofrecord flood of 1929 would not affect the water level at Nowsheraeven after 100 years of sedimentation in reservoir(refer

Illustration-II. It may be noted that this completely ignores theeffect of Tarbela reservoir,which is now factually providingrelief by attenuating flood peaks.

b) Real causes of flooding at Nowshera and Peshawar valleyupstream are: entrance of Kabul river at Nowshera into confinedchannel at the end of Peshawar valley; and backing effect ofAttock Gorge downstream through which Indus river has to passafter its confluence with Kabul river. Before the confluence.Indus river flows through a wide valley of over 8000 feet and isthen forced to pass through 1000 feet wide gorge for 5 miles.These contriction forces give rise the river water to back up,thus raising flood levels in Kabul river upto Nowshera. WhereasKalabagh would not adversely affect flooding in Nowshera andPeshawar valley above,an upstream dam on Swat River & could beprovided effective assurance against this chronic inherentproblem. Consequently, Munda Dam multi-purpose project is being

included in NWRDP.

ii) Lowest ground levels at Mardan, Pabbi and Swabi areas are970,962 and 1000 feet above MSL respectively, as compared to themaximum conservation level of 915 for Kalabagh. This maximumKalabagh reservoir level would be maintained only for 3 to 4 weekduring September and October after which it would deplete as wateris released for Rabi crops and power generation. Ultimately itwould go down to dead storage level of 825 feet by early June.Thisoperation pattern of reservoir by no stretch of imagination, couldblock the drainage and thus cause water-logging or salinity inMardan, Pabbi and Swabi areas.

iii) The invert levels of main drains of the Mardan SCARP arehigher than maximum elevation of 915 feet.Thus, these drains wouldkeep on functioning without any obstruction.

iv) Total culturable land submerged under the reservoirelevation of 915 feet would be 27,500 acres (24,500 in Punjab and

3000 acres in NWFP). The submerged irrigated land would be only3000 acres (2,900 acres in Punjab and 100 acres in NWFP).It may benoted that about 1,000 acres of irrigated land were acquired forMardan SCARP alone.

v)a The estimated population to be affected by the projectwould be 83000 with 48,500 in Punjab and 34,500 in NWFP.A liberalresettlement plan would provide alternate irrigated land to theaffected families. The affected population would be resettledalong the reservoir periphery in extended/new model villages withmodern facilities of water supply, electricity, roads,dispensaries, school and other civil amenities.

b) Another major incentive provided for the affectees inthis case, not previously practiced in Pakistan,would be to fullycompensate the farmers for the land on the reservoir peripheryabove normal conservation level of 915 feet that could befloodedonce in five years. This land would remain, the property of theoriginal owners for cultivation with the only undertaking thatthey would not claim any damages to crops for occasional flooding.

The comprehensive resettlement package proposed for Kalabagh is infact most innovative and attractive that those previouslyadopted for Mangla and Tarbela Dams. The basis objectives beingthat "at the end of day", the affectees should findthemselves in a better socio economic environment.

APPREHENSION OF SINDH.

i) The anxiety that the project would render Sindhinto a desert.

ii) There would be no surplus water to fill Kalabagh reservoir.

iii) High level outlets would be used to divert waterfrom the reservoir.

iv) Cultivation in riverain (Saliaba) areas would be adversely affected.

v) Sea water intrusion in Indus estuary wouldaccentuate.

vi) Mangrove forests, which are already threatened,would be further affected adversely.

vii) Fish production and drinking water supply belowKotri would be adversely affected.

ANSWERS:

i) Dams don't consume any water. Water is stored duringflood season and then make it available on crop demand basis forthe remaining dry periods of the year.The real demonstration ofthis came after full commissioning of Tarbela Dam in 1976. Duringpre-storage area of 1960-67,average annual canal withdrawals of

Sindh were 35,6 MAF. After Tarbela the corresponding figurerose to 44.5 MAF with over 22 percent increase in the Rabi Season.In fact, Rabi diversions alone increased from 10.7 to 15.2 MAF. Itis estimated that after Kalabagh, canal withdrawals of Sindh wouldfurther increase. This increase would come in the crucial earlyKharif cotton sowing season. Thus the often repeated apprehensionregarding de-certification of Sindh defies even the basic logic ofa storage reservoir.

ii) a. WAA of 1991 has allocated, on the average,about 12MAF additional supplies to the provinces almost all of which is inKharif season. On the other hand, factually the surplus water isavailable only within 70-100 days flood period. It is estimatedthat to provide additionally allocated water over the year, astorage of about 3.6 MAF would be needed (out of this 2.2 MAFwould be in the early Kharif seasonof April to July).

b) By the turn of the century existing three storagewould lose about 3 MAF of live capacity.

c) In lieu of these two requirements, about 6.6 MAF ofsurplus water would become available. Against this,Kalabagh livestorage capacity is 6.1 MAF. Hence there should be absolutelyabove doubt that surplus water would not be available to fillKalabagh reservoir.

iii) Initial studies have indicated that construction of highlevel outlets at Kalabagh is economically enviable.Notwithstandingthis, if any province wants to build, then its share of waterwould be strictly governed by WAA, 1991.

iv) a. An impression is also prevailing that with KalabaghDam, riverain areas of Sindh, commonly called Sailaba would gotout of production due to control over floods.Infect Saliaba cropsare grown on the land adjacent to main river and the creeks.Though crops are sown on the soil moisture soon after the floods,these need more than one watering to mature. As a result 'Saliaba'land give poor yields. Consequently, farmers are generallyrequired to provide irrigation facility through shallow tubewellsor lift pumps. Prime movers of these tubewells have to be removedduring the flood season to avoid damage.

b) Sindh has presently 660,000 acres of "Saliaba"cultivated areas from Guddu Barrage to Sea. This area is initiallysown due to the moisture provided by flooding with riverstage of300,000 cs and above.

c. Flood peaks above 300,000 cs would still be comingafter Kalabagh, without much determent to the present culturalpractices, while large floods would be effectively controlled.This would, in fact be conductive to installation of permanenttubwells to provide perennial irrigation facility in riverainareas. Towards this end, a separate scheme is being included inNWRDP.

v) a. The fear that present extent of sea water instusion inthe Indus Delta would be further aggravated by Kalabagh if notsubstantiated by factual data. Studies indicate that presently the

total effect of Indus estuary is only limited to the lower mostportion of Delta and gets dissipated below Gahro and Chowgazogauges located at Indus river. This is further confirmed by thefact that gauge heights at Gahro are completely inventive to Indusdischarges upto 700,000 cs. Therefore, the sea water intrusion,which seems to be at its maximum even now is unlikely to be

aggravated further by Kalabagh Dam.

b. Another apprehension is that sea water intrusion intoexisting aquifer system would cause serious qualitydeterioration.The groundwater contained in the aquifer is effectively saline asfar north as Hyderabad. Therefore, intrusion of sea water alongshore line of Delta is of little consequence. This is furthersupported by the fact that there is southward orientedgroundwatergradient through out this aquifer.Considering the very lowtransmissivities of the aquifer in Delta region, upward sea waterintrusion can be almost ruled out.

vi) a Out of the total 1.53 million acres (MA tidallyinundated historic Indus Delta, mangrove forest cover an area ofalmost 0.32 MA. In this forest, spreading from Karachi in theWest of Rann of Kutch in the east, 95% of the population nowconsist of salt tolerant variety.

b. Extent of the active delta area (distinct from the historicdelta area described above) is about 294,000 acres. Out of this,the mangroves cover only 7,400 acres of 2.5% of the area. Most ofthe remaining area is in form of mud flats. The reason for thisarea being too small could be a combination of factors.Recently,NED University of Engineering and Technology has carriedout a study titled "What Really Threatens us and Our Mangroves". This brings out that reduction in mangroves is essentially due tofrequency of tidal inundation being too small instead of freshwater reduction caused by upstream abstractions, which startedwith Sukkur Barrage in 19323.Other major causes are uncontrolledovergrazing and cutting due to extreme population pressure ofKarachi.

Therefore, in order to revive the mangroves, real need is forreplanting salt tolerant varieties with provision forcontrolled doses of fresh water. Obviously, this possibilitywould be much enhanced with an upstream storage facility likeKalabagh.

vii) a. A recent study has shown that there is no clear evidence

to suggest that fisheries stock in the river reach belowKotri have declined due to progressive reduction in the surfacewater supplies. On the other hand, fish production has beenconstantly increasing as indicated by statistical data. As such,Kalabagh Dam is unlikely to have any adverse effect on fishproduction in the area. b) In the riverain area downstream to Kotri Barrage,groundwater is predominantly saline or brackish and as suchunsuitable for either irrigation or water supply. After Kalabagh,winter supply in the river would improve thus assuring moredrinking water.

OVERALL BENEFITS.

On a conservative basis, the overall direct benefits ofKalabagh Dam would be around Rs. 20 billion per annum. Thus theinvestment cost of project would be repaid within a very shortperiod of 8-9 years.

CONSEQUENCES OF NOT BUILDING KALABAGH DAM.

i) National Food Security would be jeopardized, thus subjecting the economy to additional burden of importing food grains.

ii) Loss of storage capacity of the on-line reservoir due tosedimentation would result in shortage of committedirrigationsupplies causing serious drop even in existing agriculturalproduction.

For implementation of Water Apportionment Accord 1991, a newstorage project like Kalabagh is essential.In its absence it

would give rise to bitter inter-provincial disputes anddiscriminations particularly in a dry water year.Dispute betweenPunjab and Sindh on shortage of about 0.2 MAF water during Rabimaturing/Kharif sowing 1993-94 should be an eye opener.It maybe worth mentioning that Rabi 1993-94 had a normal river inflowpattern.

iv) The annual energy generated at Kalabagh Dam is equivalent to20 millions barrels of oil. This annual import of fuel for thermalgeneration,including augmentation of transportationinfrastructure, would be an additional burden to the economy.

Growth of domestic industrial and agricultural sectors would beimpeded due to high power costs.

PART G COMPARABLE ALTERNATIVE SITE ON INDUS.

The next site under consideration on the Indus for a storagefor a storage cum hydroelectric project is Basha site which hasbeen identified in the ranking study of hydel development. Onlypre-feasibility studies have been carried out. Eight to ten yearsmay be needed for detailed investigations and establishingtechnical feasibility and project planning before this projectreaches a stage of implementation at which Kalabagh Dam Project istoday. Kalabagh Project has been compared with the least costthermal power development and is much cheaper than the thermalalternative. At this stage, there is no alternative to KalabaghDam as a major power project to overcome the grave acute shortageof power. Power growth is at 10 to 15% . If kalabagh is delayedPakistan economy will be gripped by a crushing power shortage.

ECONOMIC JUSTIFICATION.

The economic analysis of Kalabagh Project was carried out todetermine (1) the least cost programme for power generation basedon an optimal combination of dam design features and operational

procedures, and (2) the overall economic rate of return on theentire investment, including the anticipated benefits from power,irrigation and flood alleviation.

Since Pakistan is projected to need about 9,600 MW ofadditional installed generating capacity by the end of thiscentury , economic analysis of electric power options centeredupon finding the least costly way of creating such incrementalcapacity.

The scenarios for Kalabagh included different levels ofinstalled generating capacity upto a maximum of 4200 MW plusvarious unit size for the generators and a range of reservoiroperating parameters and sluicing modes. An appropriate portionof the Kalabagh investment cost was allocated to power production,and all costs were valued in terms of shadow, or accounting,prices in order to reflect their true cost to the economy ofPakistan.

On this basis, the cost streams for the various Kalabaghscenarios and that for the least expensive non-Kalabaghalternative were discounted and compared to one another . At a12% discount rate, which approximates the average marginal productof capital in the Country, the scenario for the construction ofKalabagh with 2400 MW installed capacity comprising eight 300 MWunits and irrigation-oriented reservoir operation, was found to beleast costly, and thus the operational solution, the equalizingdiscount rate being 15.8%.

OVERALL ECONOMIC RETURN.

An economic rate of return for the entire Kalabagh project,in effect measuring the value of the investment to the country wasderived by comparing the expected power, irrigation and flood

alleviation benefits with total costs. Once again shadow priceswere used. Power benefits included both forecasted tariffrevenues and a conservative estimate of consumersurplus(reflecting consumers willingness to pay for the additionalelectricity).

On this basis, the overall economic rate of return (IER)wasestimated to be about 17.5% considerably above the 12 % thresholdfor judging the acceptability of new investment in Pakistan.