Penanggung Jawab :

Dekan Fakultas Ilmu Kebumian dan

Teknologi Mineral

Pemimpin Redaksi :

Dr.Ir. Lekono Mucharam

Sekretaris :

Dr.Ir. Sigit Sukmono, M.Sc.

Anggota :

Prof.Dr. Emmy SuparkaProf.Dr. Pudj i PerrnadiDr.Ir. Deny Juanda PuradimajaDr.Ir. Syoni Supriyanto, M.Sc.Dr.Ir. Sudarto Notosiswoyo, M.Eng.Dr.Ir. Budi SulistiantoDr.Eng.Ir. T.A. Sanny, M.Sc.Dr.rer.nat. Dadang K. MihardjaSri Widivantoro. Fh.D.Dr. Bavons Tiasvono HK.Prof.Di. E;ic k.f{. Goh (USM - Malaysia)Dr. M. Barzani Gasim (UKM - Malaysia)

Pemtlantu Umun,:Drs. H. Aceo KundratH. Aang Sufunta, A.Md.Tedi KurniawanSyarif Hidayat

Penerbit:Fakultas Ilmu Kebumian danTeknologi MineralInstitut Teknologi Bandung

Alamat Surat :

Redaksi Journal JTMFakultas Ilmu Kebumian danTeknologi MineralInstitut Teknologi BandungGedung Basic Science Center B (BSC-B)Jl. Ganesa No. 10 (Kampus ITB)Bandung 40132 - IndorresiaTelp./Fax. (022) 2506282, Ext.: 354 Ie-mail : info-fiktm@ffttm.itb.ac.id

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COMPUTER PROGRAMMING OI\ GROUNDWATERCONSERVATTON THROUGH DEVELOPMENT

OF SYSTEM INTERRELATION MODEL

By:Priana Sudjono'M. W. Memed

Rena'

Sari

Konservasi airtanah membutuhkan usaha terintegrasi untuk penjagaan komponen-komponen yang berhubungan denganair dari perubahan dan gangguan. Fakta litologi suatu daerah pertama-tama menunjukkan keberadaan air dan kemudiandaerah itu digolongkan kedalam zona yang pengambilan ainanahnya dibatasi pada besaran tertentu. Walaubagaimanapun, strategi zoning tidak cukup untuk mengkonservasi airtanah. Sebab, airtanah berinteraksi dengankomponen lain dalam suatu sistem komplek. Oleh karena itu otomatisasi pengindikasian tipe zona di suatu daerah dankomponen terkait yang akan diintewensi membutuhkan suatu model komputer. Komponen yang berhubungan denganairtanah diidentifikasi dan suaru sistem tentang hubungan antar komponen didefinisikan. Properti masing-masingkomponen dan hubungan diantaranya disimpan dalam database. Kemudian aturan (rule) yang mengkaitkan fakta dibuat,sehingga melalui inferensi tujuan (goal) dapat diperoleh. Hasilnya,(tnlentuklah suatu model kcmputer sebagai suatu

alat otomatis dalam memandu pemakai (user) untuk konservasi airtafili. Sistem ini mampu membuat prakiraan kondisiairtanah di suatu daerah bilamana perubahan properti komponen terjadi dan mampu memperkirakan dampak perubahanpada komponen lain.

Kata kunci : model komputer, konservasi airtanah, inferensi, dan sistem kaitan.

Abstract

Groundwater conservation requires integrated efforts to keep related components that concern with water from changes

a,rd disturbances. Facts on lithology of an area firstly indicate available water and then the area is divided into zonesthat the groundwater extraction is controlled to a certain amount. However, zoning strategy is not enough to conservegroundwater because it interacts with other components in a complex system. Therefore, an automation to indicatezone-t)?e of an area and the related components to be intervened requires a computer model. Components related togroundwater are identified and a system of their relationships is defined. Properties of each components and

relationships among them are stored in a database. Then rules to relate facts are created, so that through inferences goals

can be achieved. As a result, a computff model as an automated tool in guiding users to conserve groundwater has been

developed. It is capable in making predictions on groundwater conditions in an area when alterations on properties oithe components occur and capable to predict impacts of the alterations to other components.

Keywords : computer model, groundwater conservation, inference, and system interrelation.

Dept. of Environmental Engineering, Bandung Institute of Technology. memteq@bdg.centrin.net.id.

Directorate of Environmental Geology, Ministry of Mining and Energy.

JOURNAL JTM Vol. X No.2/2003 119

I. INTRODUCTION

As ground water conservation is a focal issue inmany large cities in Java, studies to respond the

problems have been done. However,implementation of the proposed solutions was notalways success because there are manyinterdependent related problems to be sotvEd

simultaneously. In the research, gtoundwaterconservation strategy is expanded to includewater-related components explored from localconditions then it is transformed into a computer

model. Semarang is chosen as the sfudy area

although other coastal cities can be run by the

model. The computer model on ground waterconservation developed in the research uses an

obj ect oriented computer language.

Shrdies on groundwater conservation proposed an

area to be divided furto zones related to the

availabiliry ofgroundwater sources and control on

extraction. However, it was widely known that the

strategy was not easily applied since many parties

such as industry, domestic, or public services

concern with groundwater for supporting theiractivities. Moreover, water demand in Semarang

increases as the number of population rises as

well as their activities. The water demand was 170

Iiter per capita per day then it was expected to be

210 liter per capita per day in 2000 (Arifin and

Wahyudin, 2000). As state water supply Company

strved only less than 50 percent of the

requirement, groundwater was a feasible

alternative to fulfiIl the lack of water. As a result,

the actual number of deep ',vells was larger than

the registered. Evidence was that the groundwater

table drops significantly through time (Wahid,

1998). Additionally, covering surface land withbuilding and other in-frastructures, at least, reduces

quantity of infiltrating water into soil layers.

Briefly, .it is understandable that efforts to

conserye groundwater should take account on allrelated components and thilrk them

comprehensively for solutions.

This idea is represented in a System InterrelationModel by simplifying complex relations and

interactions among components related togroundwater. Facts are stored in databases then

rules are developed in order to deduce new facts

and further to satisfy goals. Finally computer

model on groundwater conservation will show not

only zoning of the area but also relations between

activities and components and its impacts on

groundwater.

II. METHODOLOGY

Several steps to be followed in developing a

cofiputer model on gtoundwater conservation are

depicted in Figure l. Firstly, understanding the

groundwater availability and the required water inan area are found from previous studies (Harnadi,1991; Mulyono et al, 1993; Wahid, 1998; and

Arifin and Wahyudin, 2000). At the same time,identification on related components in setting

goals is taken by considering local physical and

social conditions. Next, representation of relationsand interactions between components found in the

area is achieved through development ofa System

Interrelation Model. The system is adopted as afact that is always true and then it is transformedinto an object-oriented language.

Before the transformation is done, architecture ofthe computer model is designed and strategy on

the transformation is neatly considered byramifying problems and facts. Representation offacts, ie, properties of the components and rules inreaching goals is developed in the computermodel. Finally, the computer model is runinteractively by users, and the computer responses

are confirmed with the research reports. In manycases the process should be set back to previousstages as an incorrect or inconsistent answer isshown.

Refering previous study onground water in Semarang

Cod settmg by takm, acrrfit]on local conditions I

------T_------I

Development of I

System intenelation model I___-___--r-

Design on architecture of thecomputer model including

transformation strateg y

Y,

Representation of facts and I

development on rules I-=-T-_-_

Program analysis in respondto query on conservation

Figure 1.

The method of the computer modei deveiopment

120 JOURNAL JTM Vol. X No.2/2003

III. GRO{'NDWATER RELATEDCOMPONENT IN SYSTEMINTERELATION MODEL

3.1. Components on GroundwaterConservation

Conservation can be associated with managementofnatural resources in order to protect destructionthrough exploitation and to'ensure fuhue use(Goetz, 1985). Ground water in most large citiesof Java should be conserved so that it can supporthuman activities and ecosystems. Several studieson groundwater conservation have beenconducted by Directorate of EnvironmentalGeology. The studies recommended strategies onextraction management and priority ofgroundwater usage (I1amadi, 1991; MuJyana et al,1993; Wahid 1998; and Arihn and Wahludin,2000, Sihwanto and Iskandar, 2000).

They suggesied division of the area into zones ofgroundwater extraction management and controlthat are based on groundwater yield andenvironmental sustainability. Specific criteria indeciding the zones are (a). groundwater yield; (b),maximum allowable and rate of groundwaterdraw-down (.). maximum water qualitydegradation, (d). negative impacts on environmentindicated by alterations on surface cover, landsubsidence, migration of groundwater fiom a

phreatic layer, and dispersion of pollutants. As a

consequence, Semarang region is divided into 6zones of groundwater extraction management andcontrol, ie. critical zones, sub-critical zone, safezone l, until safe zone 4.

Firstly, critical zone is located in alluviumsediment delineated by the piezomekic watertable at 20 m under the sea level, and the area isvulnerable to subsidence. Secondly, sub-criticalzone is located in alluvium sediment delineated bypiezometric water table between 10 and 20 meterunder the sea level. Both zones sustain the criticalzone and are located in coastal regions. Lastly,safe zones are located in several places that thecharacteristics are shown in Table l.

Having examined the studies on groundwater ofSemarang as the study area, water relatedcomponents that influence its existence are clearlyshown in Figure 2. At least, the componentsrelated to groundwater are catchment area,seawater, rain, land subsidence, public watersupply or piped water, and users such as

population, industry, and agriculture.

3.2. System interrelation model

Groundwater source is under the influence ofseveral activities that consume water. In etherwords, groundwater has several relationships toother components to behave as a system.Understanding the system comprehensively,computer model on conservation can be created.Even though the systems might be complicated, itcan be simplihed as in Figure 2. The figure formsa frame that enables semantic integrity constraintsto be automatically mahtained (Fikes and Kohler,1988). Components of a system are known as

objects whose reiationships among objects arestored as knowledge base.

Table 1. Characteristics of safe zone in Semarang.

Safezone

LocationGround-

watertable

(m)

Aquifer depthunder thesurface

(m)

Allowableextractionirr the zone

(m3/dav)

Note

1 Coastal zone 6-23 30 150

2 Coastal zone t7 -56 60 200

3At the foot ofUngaran mountain

+0.5 -

16,9620 - 180

Used by water supplycompany

4At the south-east attlie hilly region

25Low yield and brackishwater

Source: Sihwanto and Iskandar, 2000.

JOURNAL JTM Vol. X No.2/2003 121

y.*-i'populStion

- shallow

Figure 2. System interrelationship model forgroundwater conservation.

Figure 2 dehnes domain of groundwater

conservation and it shows interactions ofcomponents related to groundwater. Fieldinvestigations indicate that water demand

increases coincident with the increasing

population. However, to fulfill the requirement,expansion on capaciry of water treatment or pipedwater is very expensive and there is lack of raw

water from surface water. As a consequence,

groundwater is an alternative source of water

supply. In order to avoid negative impacts such as

seawater intrusion and land subsidence, the

extraction through deep wells should be menaged

otherwise this may result in a low water wellproduction. In the city, most of population use

shallow groundwater for their dome:ticpurposes, while the quality is susceptible to

wastewater poliution whether it comes fromhousing, agriculture or industry and the quantity

depends on rain. It is clear that law andregulation should also be imposed in the

conservation efforts by protecting deep

groundwater and industry should comply with astandard of wastewater discharge to surface

water- Additionally, catchment areas should be

protected agairst land-use transformation into

housing or agriculture areas in order to maintain

shallow and deep groundwater yieldr. In such

case, the amount of allowable extraction from a

basin is zoned depending on availability of water

in the basin.

As components of the system are related each

other, it creates cycles showing relations onto the

related components as in Figure 2. An example ofthe relation is shown in Figure 3 that relation of'catchment area' to 'deep ground water' then it also

relates to 'land subsidence' as guided by the

system relationships. Searching of the

relationships may be continued exhaustively as itis required by users.

In fact, the interrelationships are complex and

require quantification on each component and

explanation on the interactions among the

components. The description of Figure 2 is a

scope of knowledge acquisition to be stored inknowleCge base systems.

IV. COMPUTER MODEL DEVELOPMENT

4.1. Properties of Component

The relationships among components in a form ofa system as presented in Figure 2 require detailproperties of each cornponent. A component isbroken down to form a taxonomic classificationstructure that some samples are presented inFigure 4 through 6.

'Catchment area' is composed into 'land-use' and

'lithology' as shown in Figure 4. Land-use consists

of percentage of several land-use in a Kecamatan.

'Lithology' consists of structure of soil in a

Kecamatan and direction of groundwate. flow.

catchment area

surface shallowwater groundwater

deepgroundwater

housingAK agriculiureindustry

law and land seawaterregulation subsidence

,n.'A'.,A.etc etc elc

Figure 3. Relation owned by component'catchment area'.

shailow PiPgd**A*x

122 JOIJRNAL JTM Vol. X No.2/2003

catchmentarea

' -----_---"...-...-landuse lithologytl

percentage rockstructureof landuse area

Figure 4.The classified property of 'catchment area'.

Shallow and deep groundwater are the maincomponents in the system as they are related tomany components. Case specific data related tothese components are shown in Figure 5 and 6.

shallowgroundwater

Kecamatan except 'sea water' that is only forKecamatan located along coastal area.

The system interrelation model as in Figure 2 isadopted as always in a 'true' condition in the

computer model. Each component of the systemowns properties that are specified for each

Kecamatan. Furthermore, the relations amongcomponents are stored in database.

4.2. KnowiedgeRepresentation

Groundwater conservation strategy is initiatedfrom water balance between demand on water and

available water in an area. The required water forseveral purposes should be supplied by watersupply company otherwise it is assumed thatgroundwater wili compensate the lack of water.Analysis on water balance can produce decisionson optimal groundwater extraction given thenumber of population and activities in eachKecamatan. The ratio between the required waterminus piped water supply and the availablegrorrndwater can indicate water sifuation in anarea. Further, impacts related to excessiveextraction can be predicted and soiutions toprotect groundwater resources can be presentedby showing which components in the systemshould be mitigate<1. Conservation efforts can beachieved by increasing capacity of piped watersupply, or catchment area protection.Additionally, interventions to components andinteractions or consequences to other relatedcomponents slould be taken into account in theconservation strategy. The computer model cananalyze the situation through logical flow diagramin Figure 8. The results, then, are combined withother components as in the systems interrelationmodel. The described conservation strategy isrepresented in the computer model so thatautomation on inferences to the stored knowledgecan be achieved.

groundwaterSemarang

Kecamatan

./\'-,/\\comp't 1 etc etc

lithologyI

soil permea6ilitydepth of layer

Figure 5.The classified property of shallow groundwater.

deepgroundwater

lithology quantity qualityttlrock :tructure

depth of impervious water table Cl' Fe' Mn' etc

layer

Figure 6.The classified properfy of deep groundwater.

Properties of corrponents in the system are storedintb the cornputer model as schematized in Figure7. Components of the system are owned by each

comp't1 comp't2 etc comptl c.omp't2 etc

quantity qualityltttwater table Cl, Fe. Mn, etc

Kecamatan

---=-t/\

Figure 7. Groundwater system related to Kecamatan.

Kecamatan

JOURNAL JTM Vol. X No.2/2003 123

Figure 8. Logical flow diag

The computer model is developed based on those

figures using an object-oriented language. Theprogram consists oi groundwater database and a

bunch of rules. The rules relate facts in the

database in order to reach goals. More than that,users have opportunity to make interactions withthe computer model by inputting asked data su"has number of population or water demand percapita as ftr current or predicted situations.

Facts related to groundwater are stored indatabases, which are classified as stable facts suchas lithology, morphology, and pervious lay'er

depth. Other required time-varying data that tendto change can be inputted by users through userinterface.

In the computer prograrn, the facts can be writtensuch as:

comp onent sy s tem (p opul ati o n).

co mp on ent _sy s tem (c atchment ar ea).

r el at e d _c o mp o nent (p o p u I atio n,s h all ow jr o undwater, 1.. exp lanation of the relation...').

r elated *c o mp o n e n t (c a tc h nt ent *a r ea, d e ep jro undwater,'..explanation of the relation...').morp ho lo gr (' mij e n',' hil ly' ).s h allow 3ro undwater ltield('mu er,', 8 087 3 I 0 8).groundwater _.;flow (' mij en',' Ungaran, Kabup atenSemarang')

The above sarrples mean that components of thesystem are population, and catchment :uea.Population is related to shallow groundwater.Next, Kecamatan Mijen is located in a hilly area

where groundwater yield is 80.873.108 ,ri/y"u,and the groundwater flows from Ungaran,Kabupaten Semarang.

Rules are developed to relate facts in the database

or from screen input in order to find goals throughexhaustive search. A sample of rules in theprogram is presented below:

find_supply_demand of a Kecamatan ifgroundwater_ltield of the Kecamatan :

Q-swshallowSru;tield of the Kecamatan :

Q-ws

piezometflcelectric conductivity

land subsidence

expand pip€dwater sryice

deep grendwateryield

Logical flow diagram on groundwater conservation.

124 JOURNAL JTM Vol. X No.2J2O03

Groundwater :Groundwater yietd: Qgw m3/yearShallow groundwater yield = Q-sw

*'/yeo,

Reguirement on Shallow eroundwater :Number of population: ?

read(Population)Percapita water demand (/day) = ?read(Demandltcpt)Piped water supply sertice (n : ?

read(lYatSuppl)Demand on Groundwater :

Number of deep wells : ?

read(Gw well)AverageJlow (/min) : ?

iead(Gwlflow)

Qto t _domes tic : P op ul atio n * D ema n d ltcp t * 3 6 5 / I

000

Q _extractio n _s gw : P o p ulatio n * Dem a nd lcp t * 3 65 / I 00 0 * ( I - (WatSuppl/ I 00))

Q-extraction gw: Gw _well * Gw _1fl ow* I 4 4 0 * 3 6 5 /

t 000Total demand for domestics: Qto t _d o m es ti c, " m 3 /y e a rS hallow groundwater extraction:

Q _extract i o n _s gw, " nt 3 /y e a rDeep groundwater extractio n:

Q *extraction gw, " m 3 /y ear

rt n d _ra t io (Kec a m a t a n _n a m e, Q to t _do m es t i c, Q *ext r o c t io n _s gw, Q _extr actio n gwQ _o p t i m a I _s gw, Q _o p t i m a I 3w)1-he above sample program can be explained as

lollows:I dtially, the program will find deep groundwater

1 rld and shallow groundwater yield at a givenK rcamataq ie. Qgw and Q_sw m3/year. Next,th,: program asks for the demand on shallowgroundwater. These are the numbers ofpopulafion, water demand per capita, and thepercentage of population served by piped water.Tiren, the program asks for the demand on deepgroundwater. These are the number of deep wertsand the average flow of deep groundwaterextraction. After that, the program conductssimple arithmetic operation on total domesticwater demand, possible extraction on shallowgroundwater, and average extraction on deepgroundwater, and echoes the results to the screen.The formulae are

Qto t _do m es tic : P op u I atio n* D emand 1c cp t * 3 6 5 / I000

Q *extractio n _s gw : P o p ulatio n* D eman d 1 cp t * 3 65 / I 0 00 * ( I - (ll/atSupp U I 00))

Q _extraction gw: Gw *well * Gw

-flow * I 4 4 0 * 3 6 5 /

I 000

The results of the corrputation will be used to findratio between demand on water and the availablegroundwater through rules :

fi n d _r a t i o ( K ec am a t an _nom e, Qt o t _d o m es tic, Q _extr action _s gw, Q _extr action gwQ _o ptimal _s gw, Q _o p tim al gw)

Finally users will get an answer based on thesituation of groundwater in the specifiedKecamatan. Further, impact of such situation toother components of the system as depicted inFigure 2 can be found easily by specifying a

concerned component.

A part from that, user-interface is very importantin the program in order to make users easy inhandling such a complex groundwaterconservation system. The user interface makesinteractions between users and the systempossible. The flow of searching decisions on theground water conseryation is guided through theschematization in Figure 8. The main menu isrewritten as follow:

GROUNDIYATE R CONSERVATION INSEMARANG( I ). General information(2). System interrelaticnfor groundwater inSemarang(3). Groundwater conservation in Semarang(4). Terminate the programNumber of interested topic (l-4) :readintQ'Iumber)

fi n d _in t er s t e d _to p i c Q,l u m b er)start

The above computer program echoes menu to bechosen by users. As the number of interested topicis gped up, the rule on'find_intersted_topic(Number)' wlll be executeduntil the results are found. The user-interfacesystematizes and guides users in exploring thecomputer program as it is required.

V. CONCLUSION

Conservation does not mean only classifying anarea into zones of allowable extraction. But it alsocovers related components in a defined systemwhen a component is intervened by humanactivities. Interaction among components is

JOURNAL JTM Vol. X No.2/2003 125

complicated and processes within componentsrequire experts to explain.

To conserve groundwater, water relatedcomponents are identified. Using expertknowledge, components are related each other toform as a system. Each component has its ownproperties and behaves interdependently amongother components. The description of the systeminterrelation model is transformed into a computermodel using an object-oriented language. Stablefacts and also the properties of each componentare stored in database. Moreover, a strategy indeveloping the computer model is created bysetting goals on conservation. In order to reach thegoal, inferences are required by developing rulesthat related facts through certain procedures.

Finally, the computer model can be a useful toolin guiding users to conserve groundwatercomprehensively because the computer modeldoes not only indicates zone type of an area, but itis also capable in making predictions on an areawhen such conditions occur. Additionally, themodel indicates related components in the systemto be intervened as the conservation ofgroundwater is concerned.

REFERENCES

1. Finally, the computel model can be a usefultool in guiding users to conservegroundwater comprehensivelybecause the computer model doesnot only indicates zone type of anarea, but it is also capable inmaking predictions on an area whensuch conditions occur. Additionally,the model indicates related

. components in the system to beintervened as the conservation ofgroundwater is concerned.

2. Fikes, R., and Tom Kohler. The Role ofFrame-based Representation inReasoning. In Principle of ExpertSystems Ed: Amar Gupta andBandreddi E.Prasad. IEEE Press,(1988): pp.94-1 10.

Goetz, Philip W. Ed. In chief. EncyclopediaBritannica. Vol.l5, 1985: pp.553.

Harnadi, Dadi. Survei Konservasi AirtanahDaerah Semaranq dan Sqkitarnya.Directorate Geology andEnvironmeht, Department ofMining and Energy of Indonesia.Report no. 68/FIGKA/1991. (1991).

Mulyaiia, A., Warsono, S., and Boetje R.Denny. Konservasi AirtaSemarang dan Sekitarn.va.Directorate Geology andEnvironment, Department ofMining and Energy of Indonesia.Report no. 82[HGKA/1993. (1993).

6. Sihwanto and N. Iskandar. KonservasiAirtanah Daerah Semarang danSekitarnya. Directorate Geologyand Environment, Department ofMining and Energy of Indonesia.Report no. 36/LAP/PHP N1994.(2000).

7. Wahr<t, Hendro. Konservasi Airtanah DaerahSemarang - Demak dan Sekitarnya.Directorate Geology andEnvironment, Department ofMining and Energy of Indonesia.Report no. 4O/LAP/P[{PN1999.(1ee8).

Appendix

The appendix shclu,s some samples of outputprogram resulted from interactions between usersand the research-level computer model. Mainmenu consists ol general information about thestudy area. interaction among components in thesystem, and conservation uf -groundwater.

Figure A1. Main menu of the Program.

In case first choice or general information ischosen, morphology and hydrological conditionsof the study area will be shorvn on the screen.

Figure ,A.3. Components intactin a chosen Kecamatan.

5.

3.

4.

126 JOURNAL JTM Vol. X No.2/2003

In case menu number 2 is chosen' the prograrrl

will echo all Kecamatans in the study area as in

Figure A2. A user may choose one of the

Kecamatan, then the program shows components

that are intact in the Kecamatan and whether the

Kecamatan is located at a coastal region. This isshown in Figure A3. For example, 'deep

groundwater' is chosen, then everything related to

'deep groundwater', ie. quantity and quality, in the

Kecamatan is shown and the program also

indicates other components that are reiated to

'deep groundwater'. The user can continue to other

components to understand its relationships and

case specific data of the component in the

Kecamatan.

Figure A4. Question and answers

on conservation.

In case number 3 or groundwlter conservation is

chosen the fist response of the program is

showing all Kecamatans in the study area. After a

Kecamatan is chosen then the program will show

morphology and rock structures that are classified

as stable data. Interactions with user take place in

order to input time-dependent data such as

piezometric depth, water conductivity, and land

subsidence. Then the program will conclude zone-

type of the Kecamatan and the amount and depth

of the groundwater. Following this, the program

asks for, through the screen, the number ofpopulation, water consumption, percentage ofpiped water services, number of deep wells and its

extraction. Then the program will show total

water consumption, extraction of shallow and

deep groundwater. Furthermore, information on

the amount of available groundwater and

locations of the recharge area will be shown in the

screen as in Figure A5.

Figure .A5. Available water and catchment area to

be Preserved.

JOURNAL JTM Vol. X No-2J2003 127