DESIGNING PROJECTS FOR THE DEVELOPMENT O F GROUND WATER RESOURCES IN THE ALLUVIAL PLAINS OF NORTHERN INDIA ON THE BASIS O F INADEQUATE DATA,

BY

B. K, SABHERWAL

ABSTRACT

Utilization of ground water potential to develop irrigated agriculture in the alluvial plains of Northern India through "Push button" water wells has played a vital role to bring about the Green Revolution for meeting country's food deficit. But the positive development on the food front is only a phase. Continuing population growth and the resultant increase in demand for food, fibre and other services obtaining from water use are adding t o the water requirements thereby underlining the urgency to hasten execution of projects capable o f delivering assured water supply to meet the demands of high yielding varieties (-HYV] crops, This can be achieved by installing more water wells in the alluvial plains of India rich in ground water potential. Ground water resource though it gets replenished annually, is not an inexhaustible resource, Ecological responsibility makes it incumbent on the planners of ground water development projects that this precious resource, I S not exhausted due to over exploitation, Surface waters are tangible and their potential can be predicted upto reasonable certainity on the basis of long term observations of flow in channels. Assessment of ground water potential on the other hand is quite complicated. The difficulty arises on account of the fact that ground water relates to that invisible part of hydrologic cycle which occurs beneath the land surface. Evaluation o f ground water resource to a high degree of accuracy is a multi discipline study involving, collection, analysis and synthesis of hydrological, geological, meteorological, geophysical, hydrochemical data, computing quantums of recharge, discharge and balance of ground water in a basin or a sub-basin and correlating the results with the changes i n ground water levels and its regime, A comprehensive study o f this type is time consuming and costly, In view of the latest developments i n ground water hydrology the available hydrological and geological data is not adequate enough for a comprehensive and precise assessment o f ground water potential though exploitation of ground water in India commenced quite some time back. On the other hand preparation and execution of plans and schemes for the exploitation o f ground water cannot be held over till the completion of s u c h a study which may take four to five years, ît has therefore become necessary to adopt some reasonably accurate methodology t o evaluate the ground water potential with the help of the available data and plan ground water exploitation projects on its basis though at the same time keeping margin for subsequent adjustments when better data becomes available, Appraisal techniques and adopted criteria for an approximate evaluation of ground water balance in water table aquifers are described with particular reference to the Bist Doab Tract of the State of Punjab-India which has an area of 9000 sq. kilometers and where 80% of annual rainfall occurs in the months of July to September. Significant part o f the assessment study is the recharge to ground water from the annual flow of about 1.25 M.A.F. of; surface water thorough a net work of unlined and lined irrigation canals and its ultimate spillage in the cropped fields. O n the

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discharge side is the drawal by approximately, 0.1 million existing shallow and deep water water wells which are either electrically or diesel driven. The electrically driven wells have unmetered electric supply, the tarrif being on the basis o f horse power o f the electric motor. For both the tupes of water wells log books recording the number o f hours a tubewell operates are not being maintained by the private owners, This aspect further adds to the problem o f working out accurate drawals from and return seepage t o ground water in tubewell irrigated fields, In the absence of adequate data to correctly evaluate ground water potential and pressing necessity to exploit the potential for food production statistìcal or empirical methods have been adopted t o work out ground water balance and then apply a reasonable safety factor to take care of short comings in the approach. In the project areas water table fluctuations are also being observed more frequently t o closely watch the effect o f additional draft,

RESUME

L'utilization du potentiel des eaux souterraines pour le développement de 1"agriculture irriguées dans les plaines alluviales de l'Inde du Nord a u moyen des puits d'eau d u button-préssoir a joué un rôle vital pour accompler la "Revolution Verte'' afin de satisfaire les besoins deficitaires des aliments du pays. Mais le développement positif sur le front de nourriture n'est qu'une phase. La continuation de la croissance de la population et l'augmentation resultante du besoin de nourriture, tissus, et des autres services utilizant l'eau necessitent les besoins de l'eau supplementaires, ainsi soulignant l'urgence de l'ëxecution des projets capables de l'alimentation fourniture assuT+e d'eau pour subvenir la demande des récolte de haute z-eqdement. On peut satisfaire cette demande en installant plus de pults d'eau dans les plaines alluviales d e l'Inde du Nord, riches en potentiel des eaux souterraines. Des ressources des eaux souterraines quoiqu'elles se remplissent chaque année, n'est pas une ressource ingpuissable. La responsabilité écologique le rend obligatoire aux planificateurs des projets des eaux souterraines de voir que cette ressource prlcieuse ne seppuisse pas, en raison de sur-éxplóitation. Des eaux de surface sont tangibles et on peut prédire leur potentiel jusqu'une certitude raisonnable sur la base des obser- vations à long terme de l'écoulament des eaux dans les canaux. L'esti- mation du potentiel des eaux souterraines par contre est bien compli- quee. La difficulté s'8le've en raison du fait que l'eau souterraine se rapporte à cette partie invisible du cycle hydrologique qui se fait au-dessous de la surface de la terre. La nature héterogene des formations géologiques à travers lesquelles l'eau souterrasne circule rajoute à la complzxitê du problame. YaloTisation des ressources des eaux souterraines a une haute degr6 d'exactitude est une étude de dis- ciplines multiples comprenant recuîl, analyse et synthese des données hydrologiques, géologiques, méteorologiques, géophysiques et hydro- -chemiques, calculant les quanta de récharge, d@scñarge et le bi'lan l'eau souterraine dans un bassin ou sous-bassin et mettant en corréla- tion les résultats avec des changements dans les niveaux d'eau soute- rraine et son régime. Une étude detaillée de cette type demandes plus de temps et est coûteause. En vue des plus derniers dêveloppments dans l'hydrologie de l'eau souterraine la données hydrologiques et géologi- ques disponibles ne sont pas assez pour une estimation complJte et

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exacte du potentiel des eaux souterraines, bien que l'exploitation des eaux souterraines commence il y a quelque temps dans le passé. D'un autre cote, la préparation et l'dxecution des plans ou schemes pour l'exploitation des eaux souterraines ne peut pas &tre arrêtées jucqu'a la complétion d'une telle étude quì puisse prendre, 4 ou 5 ans.Donc, i1 est devenu nécessaire d'adopter une méthodologie raisonnable exacte pour estimer le potentiel des eaux souterraines avec l'aide des donnêes dìsponsible et planifier des projets d'exploitation des eaux souterraines, au même temps en retenant une marge pour les modificatìons subséquentes quand p+us de données seront disponlbles. Les technìques d'estìmatïon, pour une valorisa- tion approximative de balance d'eau souterraine decrite avec une réference particulière à BIST DOAB tracte Etat de Punjab en Inde q u i a un terrain de 9000 kilometres-carres et ou 80% de pluie annuelle arrive aux mois de Juillet.Septembre. La partie signìficative d'6tude estimative concerne la récharge 2 l'eau souterraine de l'écoulement annual d'environ 1.25 M.A.F. (million acre pieds) d'eau de surface par un réseau de canaux d'irrigation alignes et non alignes, et son utilization ultîme dans les champs cultivés, A cbtk de déchargement 1.0 million des existants puits d'eaux qui sont opérées soit par electricit6 soit par essence. Des puits mechanizes par electricit6 assurent une alimentation d'eau sans compteur d'electrictricite, le tarrif étant basé sur le C.V. des moteurs eléctrlques, Pour les deux types de puits d'eaux, des carnets à régle concernant le nombre des heures qu'un puit S opére, ne sont pas tenus par les propriétaires prives. Cet aspect ajoute encore au problème de calculs des puise- ments exacts de l'eau souterraine dans les champs irrigués a u moyen des puits à moteurs électriques, Dans l'absence de données de valo- riser correctement le potentiel d'eau souterraine & la nécessité pressante d'exploiter le potentiel pour la production de nourriture les methodes empiriques et de statistiques ont Btd adoptées pour retrouver la balance d'eau-souterraine et d'appliquer un facteur raisonable de sÛréte de bein rendre compte des fautes dans la mainère d'aborder, Dans les regions sous observation on étudie aussi tres souvent le niveau de variabilité d'eau pour remarquer de pres l'effect d'eau puisée en supplement,

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1. UTROWCTICN 1.1 India i6 the seventh largeet country in tbe

World. ït's area is 328 million hectarest 3-28 million bqtlue iiiïorn9ters) with a population of 547 million (1971) Agricultural out put accounts for half of thr country's Gross 23: tioneï droductí GPW.

1.2 In the year 1947 wheu the country was divided, the major irL-i;jation syskais únd %cod piav~ucLi? ?reas were lost to rtkistm resuïtiag ILI a deficit of 4 dillions t m m s of food grains. India had tbrefcm to iwort ,ILL t;.c's.us from the major wheat producing countries of the world till the advent of Green devolution recently brought about by the'incrrased utilization of country(s surface water resources for irriyqtion from 93745 priïlion ~1 m (76 million acre ft.) in IL361 to 222000 milîion CU m ( 186 miliion acYe a.) at Grosent ?nd tof ground water lli000 Pilllion CU m (I30 million ecre ft.) üse í~f high yielding variety (W) seePS of cercnls hke wheat ,rice,wiize,Jawar and Bjra hes Ris0 hastened to a great extent the tremendous increase III 'food cut put. Cevelopmgnt Of rtwarf varieties of wheat made Possible following the introduction of valuable genetic material from bxtco 141 1962 has alone increased the production of t h b important cereal from neerly 12 to 23 million tonnes within a period of about five yeam.

1.3 Eilt the maximm production per unit of any Particular variety of m d seed is the result of a set of cultivation practices proper doses o9 ioputs prophylactic and curative measures to check the atta& OP insects, pests and disewes end above all adequate irrigation at proper time. 2. INDIA-PH!EICAL AND OTHE=TI FJ3AlWRES.

divided into six divisfons comprishg of i- 2.1 Physio raphially Indkais main land can be

i) the Himslayan mountains ii) the indo-Gangetio Plains

iii) the Central Hiagi Unda the D e c m Plateau the Eastern Coastal Belt

vi) the Western Coastal Belt 2.2 The Himla moimtains are of comparatively

recent origin. The Deccan Eteau end the CentraR Hi@ Lande are composed of ancient rocks. The Plains are hilt up of layers of sends, clays of molo loally very recent &te. The metern anditestem Coastal befts comprise of deltaic and sedimentary marine deposits.

About 7of of the country's a m a is under lain by hard rock with a thin soil cotrer at top derived fra l%o wealtherinn of rocks. IO 1i, mainly the Indo-Gan etic Phkis and the two deltaic Eastern and Westem Coastal d t s which are made up of alluvial solls and sedfmentwy deposits varying in thickness from a few hundred feet ln the coastal belts to thousands of feet in the Plains.

and respond well to artificial irrigation. Being generally permeable in character and having laysrs of coarser deposits also provide under ground storage for seepage water. NO wonder the Indo-GangetLe Plains, 8nd the tu0 coestal belts though accomt for on1 l./3 of the oauitry'e laad rnam ?ut suwort atmut of tL caintrps pornlation.

the triaitaries of the U&s, the cianges and the Bwhaii Putra flow rlugyishly through the indo-Gangetic Blain. The main rivers

2.3

2.4 Ailuviai soils are suitable for agricultum

2.6 The maor snow fed riveris of tu country naaiely

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flowing to the coastal belts are the Xarkda and the Tapti on the western side Cmd the Maha Nadi, the Godavari, the Krishana rind the Cavery on the eastern sir%. All these rivers outfall into sea. The rfvers also provide irririation supklies to the vast net work of m a l systems part of which was constructed about a century back. host of the old canals are designed as

Il m n of the riveril schemes and are unlined. The unlined cana.ls act es additicnal souY'ce of recharge to ground water besides seepage from rivers, streams and rainfall.

oceanic, from extrems of heat to extrerns of cold, Prom high a.ridity a.nd negligible rainfall to excessive humidity and torrential rainfall. Sauth destemi monsoons in summer accounts for m r e than 85% of the precipitation and that too in a short span of about 4 months. The great diversity in weather conditions and uncertainity of rainfall results in the prevalence of draught condition in about one third of the country. 3. GROW D :,! AT-g 2 17s

3.1 rsinfall and also lack of' adequate storage support for some Of the major canal irrigation schemes, tappin:? of zround water resource through iiells and tubewells for intensive agriciiltu re has pla ed a yitzl role in ushering the (Green Revolution

distributed rainfall is quickly lost thrm$l evaporation Ixit where g-ound watnr potential is available stored in alluvial deposits

intmsive cropping dernad water at the right time and of the rewired quantity. These pre-requisits have made the cultivators in areas with copious ground watcr supplies take to the instcllatïon of their own', push aittontt irrigation systems. The water scarcity during the yesr 1365-67 which created draught conditions almost all over the country acted as catalyist to boost up exploitation of ground water poteiitfal thmu& diesel or electrically operated tubwells 100 feet to 200fbet dealfor the protection of Crops.

3.3 The Govemrcent also rose to the occassion and undertook to provide large saale loan finance to the cultivstors. for the installation of tubewells on their farms in areas where the ground watcr potentialities were promising. The result is that at present an investment of about Rs.2000 crores hac Filreacbr bean Lade in the field of ground water exploitation in the country. Most of this investment has taken place in private sector.

insxellation of tubwells in the a3untry:-

2.6 In dia s clima. te ranges from con t in en ta. 1 to

In the face of variability and tirircliability of

particu Y a.rly in these parts of the country where low or badly

3. 3 Cultive.tion of high yielding varieties and

3.4 The following table, indicates the progress Of

(In thousands I 2 5 0 1965 A969 1971 (anticipated) - - -.-

Mo.of private tubewells 3 100 279 470 rio.of diesel pumps 66 471 837 1150 No.of electric pump sets 19 513 1080 1620

Total 88 1084 2196 3240

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3.5 The spectacular development of ground water utilization in the country has been influenced by a npmber of factors namely the rzcognition by farmers of the importmt role played by ground water in sustaining modern agricultural techniques, incrceaed availability of institutional credit for financing the ground water exploitation programme, rapid electrification Of rural areas, local availebility of technical h o w how to drill well8 with machines, and indiyenously manufactured pumps, motors and other equipmat for the construction of wells and above all large scale village road deve lopmen t p rogr amme .

3.6 schemes and the involvement of the Government back institufional credit far the purpose has made it incunibent to plan and execute this programme of utmost natio'lal imoortance duly sumorted by proper assessment of ground water potential.

Heavy investments in gound water exploitati.

4. HYDROLOCEIC CYCB. 4.1 All the waters in existance en be located by

what is ïmìwn as 1) hydrologic cyclen or 11 Nater Cycle". This C cle involves total earth system comprising of the atmosphere, d e hydro-sphere Snd the lithosphere. The activities of the n ilater Cycle" are vast extending from an average depth of about half a mile in the lithosphere to abcut 10 miles in the a tmsphere . geologic history of a particular area. If the geology consists of alluvial fmnatlons, water will occur in the openings between granular XcFosits; EUT; if the area fOr~tiOnS are rocky, the ground water Will be found in decomposed parts of ro&B, freotures or in tabular openings in soluable rocks or opening in lava formed by flow or gas expansion during solidification. Guide lines to evaluate ground water potential in alluvial formatias have only been discussed in this p3Per.

4.3 Ground water originates from surface water and gets renewed or recharged with the down vard percolation Of precipitation, flow in stream, canale, return flow f r a irri,ated fields etc. Propm assessment of this valuable resource fomd in Permeable geQlOgac formations and in motim through the voids or pore spaces in an area requires working out its total storage and quantities whir& are annually pumped out or replenished into the ground water reservoir. bality Of grOUnd water .leo requires to be known. Comprehensive studies and explorati-ns -re necessary to evaluate the potential to a hfgh degree of accuracy.

4.2 Hydrologic cycle is greatly influenced by the

5. APPRbACH TO WORK OUT GRWdD WATER BULLANCE; ON TI% &.SIS OF INADECrJATE DATA. 5.1 hthodology for the precise eva2natioB of ground

vater potential is quite complicated. The difficulty arises 691 account of the fact that ground water relates to the.t invisible

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pert of hydrologic cycle which occurs 'beneath the land surface. 9etero~~eneoUs nature of the ,(.f?ological format ions through which ground water moves e-dds to the coarplexity of the problem.

which is the Northern-Western part of the Indo-Gangetic Plain alluvial materials constitute an extensive hetrogeneous and a.nisotropic unconfined aquifers . Discharge from tubwells as deep a$ 300' results in- draw-down of water tsóle over larye prea. ?nd is sustained by dawrltering of surface watr,r recharne, such condit iow jrevail through out the top aauffers ~f slluaiurn.

5.3 Planning and designing of ground vmte? development through small and medium sized tubewells (1.10 to 200 feet deep) in the ground water &sins and sub-basins o0 the indo- Gmjetic plain ' cím therefore be ,compared to re:.err)ir prObLem. This approach cal-1s for drawing iipm the fresh water table a,quifem upto the Safe Yield which should not. exceed che long term mean -annual supply or recherge involving wet and dry years. In view of lack of complete data the genersl. i"om CJf bhe squrtie.cn of hydrologic equilibrium in thcs project areas has been simplified cmd suitably adjusted to arrive at worh.ble ,g:rourid ;iater hiance. In areas having ground water quality problem Safe Yield cannot be equated to mean annual recharger

irriz8tion is being practised in India since 19.34-36. In edditìon, tubwells vere a.lso install.ed Por municlpal,rai%ays Tnd indust, ia1 use. Geological Survey of India, state Zrri%ticn &partmats and Central Gróund -.:a.ter Board have bom iminte.in1ng oeological, hydrological, geochemical and other ground water data of a rudimentary character. Irrigation Departnlsnts have also meintahed record of water table fluctuations keduced to mean sea level ( 1%.Lr) from a net work of observa.tion wells. kmccipitatScn, racord is kept by Indian bieteorological Department. Ifit no are?wlse systematic investi.zations and exploration to a-ssess ground water potential were conàucted. In the absence of adequate ùata to evaluate ground water potlontkal on the basis of lat$st deVelOPI~ent6 in g r m d water hydrology and pressing necessity to exploit ground water potential statistica.1, analytical and empiriel wtbods were resorted to arrive at preliminary quantitative evaluatîon of ground water balances in the pro,je ct areas

5.5 computed on the collp,ction and malysis of the following basic data in project areast- 1. Village -wise iocatim5 and other details of existing

tu heiaelle 2. Colleetion of reliable litholo- of tubewer-ils. 3. Iso-pstch featums E@ revealed by litho-lons and

5.2 It ha.s been observed by pump tests that in Punjab

5.4 Installation af tubewci-11s upto 300 feet for

Ground water balance te Plan schemes was

geologid correlation of strata upto the available depths to broadly understand t.he geometry of aquifers.

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4.

5.

6.

7.

8.

il.

10.

11 0

12.

13.

14

15 . 6.

,Sample observatiais of pumping rates o? existing tubewells by u s h g simple devices(0rifice or ri,qht Angled '6-notch) . dimple surveys to assess pumping hours for surn'lier and winter crops to work out present ground water draft in the Gi'oj ect .-;.rea. Locatim of raingaue stations m d annual ra.infel1 datn. for the last 20 to 30 years. '

::eighted mean average annual rainfall fill;ures for different blocks of the area by Theisson method. Locations of existing pugln?JdischPrp sites on stresms, drains and CO! lectfon of run off data monthwise. Available ground water qiality data to demrcate fresh and inferior ground water zones. Location of existing c m e l irriyation s,Ftem m d data about their len$.hs ,. sectims,( lined/unlined) desiled dischzcrges, actual flow time and areawise. Yeriod-wise flow in enals Rt the point OP entry into and exit from the project area. Locations of existkg water table observation wells and past data of tiatcr table fluctustbas for pre and post monsoon periods hater table depth data to delineate high water table areas . Cropping pet tern, cropkning cslander and water requirements for summer and winter crops. :,orking out zvera- value of specific yield of the formations, either by pump tests or empirically. TJXH1vICk.L CRITl3RI.A FOF GROTD ?dUKE PLZ./L".JJCI: C0PîJT;RTIDN.

Technical criteria adopted to work out ground water balance is given as under:-

6.1 Rechars oroni R&infall Unconfined %quifers get recharwd from local

rainfall. Based on the sQiilles ccnducted in the Ganges &sin for period 1937-78 to 19Sû-51 a relationship vas evolved to WO& out net penetmtim of rain water to water teble in alluvial areas

2/5 Rp t 2*O(R-15)' 'Ihere R average annual rainfall Zn inches.

Rp = annial rainfall penetration to water table in inches. ïhis relationship applies to areas having

annual rainfall in excess of 15". 6.2 beemge from Canals

seepage loss values from unlined canals based on

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experimental data are given below. These figures are inclusive of evaporation losses which form only a small proportion:- i) In the :tete of Uttar Brzdech-ïndia it is about 8 Cs.

(GU ft/:iec.jfor ordínary clay loam to about 16 cs.for sandy loam Per million 5;q.feet of wcttad parameter. i,verage king 10 CS ./k.qt .

li> In the Wz1iarashtr.a State-India these sire calculated at 15 Cs./M sat. for discharse upto 250 CS. anil lO.&s!./M%ft for hiisher discliarzes.

iïi) In FunJab and Haryana state -India =lue, of ..eepa<e loss in Cs./ìvI e f t p is zxpressed by the formla :-

for unlined chmnels -.O6 25 (a) K8 4x4 d .O56

KE ix; for lined channels. where K is the se.epa.ge in cusecs pfx million square Feet of wetter area anci Q is. the discharge in channels in cusecs (CU ft,/riec.j

6.3 Recharge from Mater CouI’ses. ,According to the findinqs in the Crop Planning

Committee Report of 1954 for Phakra canal meas in ïuiijab, out of the total quantity of water that enters a canal at head, nearly 45$ is lost during transit In canal, diatriaitaries a d water courses. This means that for every 109 cft of water received in the field 182 cft of water is releaspd at the cm31 hend. Seepage loss in water courses also is tczken ES 20% of the flow.

6.4 Retuin seemge from irrigated fields. PPrt of irrigation water spread on field

percolates below the root zone of crops m d is added to the .ground water body. !:;hat percento9 of the water spread for irrigation crops percolatcs riown depenas on character of soal, types of crcp 2nd quant.ity of watering and its frequency at,?<

AccOr6iang to Crop planning Committee 1iepqJ39~ Rhakra C2na.l .&rea referred to above out of 100 cs water ;,te-;,,. reaching the field 70 CS. is utilized by the crcp plant ” &$i; ., the remaining 30 CS. goes under mound.

6.5 Recharge from Hilly Stream and S t o m water Drains.

It is difficult to exact ìy analyse.! caused because neither the c:uantum of flashy disch9?ges no.? the sections of the hilly Streams(Choes) a parameter has been evûlved on the basi Last bins stream in Bist Doab Trmt o approximation to the seapage precipita through the numerous choe beds is taken asss?

6.6 sub SUPface Flow It has been observed th&-

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alopes of the $round water table in the $lains the quantity of subterrainem flow g ~ t t h g $.h and out of project are- is negligible 2s conipared to vertical recharge from rainfall, cmal P B ~ P U ~ L , return flow from irrigated fields etc. Hen- this item has been omitted from computatiuns on both sides of hydraulic equation amialy due to' the non-availability of adequate data.

Ground wqtrr loss due to non bene3tçkl etrapo-tranepiration in water logged areas.

of water table froin th@ ground surface 81.14 vegetatkq cover. Airing July to October period when recharge to grow-d water reservoir is maximum Qe to rainfall and high supplies in rivers and canals etc. water table rises towards ground surface. In the riverain md water Jogged tracts, the depth of Found water veries between zero to 6 feet below lanu surface. in 1963, 'J.S. B.RI conducted experiments/ obervctiuns for salvaging ground water t6i?g evawqsteü from ground LI' transpired non beqeficially by vegetation In the central part of san-his Valley, Ceil'tral Coloredo ( U.S+) t Graphs were plotted, correlating E.T. loss to ground water depth E.T.loss th negligible if water table is lowered to 12.5k

Persistance of higher water table 5r water logged amas indicates that recharge to ground waster is equivalent to the E.T.loss or may be $ven morg. Pending detailed studies, it would be reasonably p o d planning to draft grouad water within the limits of water est9rnated to be lost through evapo- transpirat ion.

6 08 Draft froor the e x h t h g state (deep) and Arivate (shallow ) tubewells.

ere planaad to operate at 22 hours a day for 240 days in a y6arr H e n œ d m a l draft from state Tubewells varies f r m 660 acre ft. to 880 acre ft. Shallow tubeiwslls (0.2 to 0.8 cs.cepacity) for a b u t 800 to i000 hours per year. Draft f r a these wells cm b taken as 15 acre ft, to acre e, per well per year. por wells driven by animal power dralpt Is taken W 5 acre ft. while for drinking sugply wells in villages the draft 1 acre ft. has been adopted per mimam.

interfpence due to ovQr fapphg 09 their ocrnes of depression. In ~ thi&y populated &we&9 of the IndolGangetic Plph@ Qr a b r y Basin ? m m ho&&hgs are very small < abcut 10 to 15 acres per head ) . The t u W e l l s aro of 0.2 to 0.3 cubic feet/ $eco dfaeharge and 100'-190' deep. These wells do not run more than 10 to 15% of the time in a year. After tests results minimm epacinp of such wells has been kept at abut 600 feet 6

6 r?

EvagotreEspiration losses ars related to depth

The State tubewells ( 1.5 to 2r0 CS. cawcity)

6s 9 SpaqIpg q$ shallo~ tubewells, ' Closdl spaaed tubewells muse mutual hydlaulic

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6.10 Grotmd WatEr Ealmce Computing the item of ,annual recharge and

discharge as por criteria discussed above if a balance is struck 5 first estimation of the balance of T2cbyze potcntntlal in a Project crea beccmes laown for planning further explcit-ticq. A reasotinble factor of safety can be adopted to plen exploitetim of the comnuted ground water ImiBncs which tcakes care of the saps in the available data or the appraisal approech. The fa.ctor will depend on area conditicns. 7. GHOTjND b~dkii BLLA.?JiCG IN B145T DCAB 'I'R.'ICT

7.1 Bict Doab is a triangu1a.r part of the Punjab StF.te ( India ) enclosed the rivers Sutlej and the Beas on

third side. Three districts of the state ncmely Jullundur , doshiarmr and Kapurthala are located in th;c tract .

7.2 The area of the trect is 9900 Fq. Kilometers mostly mugrising of alluvial plpin except the 8 miles wide belt of Shivalik Hills on the XGrth-eestorri ,?id&. depth of alluvium in the plain as revealed by seismic surveys is thousends feet.

plains. Avcrzge ?.nnual rainfall in hilly region 1s 1200 mms tJhils in the plains it varies between 914 mm tc 635 mm. 80% of the rainfpll occurs during the monsoon period.

gromnd water supplies. There are abcut 0.2 million irriqatiw tubwells clnà dugwells in the area. Quality OP grmnd water is qood for cultivation.

eanal which draws its supplies fYom the barrage on tho river Lutkj at Rupar. Abut 1.25 M.A.F. of water is used annually for cultiva.i;ion. The net work of canal system Measures 7,54.28 Lilcirieters out of which 34.5i) Km. is lined. mcthcr feature of tile; area is ;iutiierous hilly utrea=( clioec) which descend from the :,hivz~lik hills and fiord only &i.ing monsoon period w ith flashy uischw .;es

work out the ground Kater bzlance in the m e a dis+;rictwise are talxilated 88 per stateuats i & 11. .A safety factcr 0.60 has been cùopted to the computed figures to arrive a.t the exploitable grourd water stential. The water ttible f1uctuatir:ns end the rainfall hi the area 8i-e being closely observed to watch the strezses m d strains covered by ground water exb>lcitat*on on the shallow unconfined aquifers under water table conCAtions 8. ca4crusCáu

8.1, populatun is likely to inn,ease to 700 millions by the end of the present dea&. On the kcis of the piiojecte8 growth rate

t?:c ciäes and a i v a l u hi1 9 s (lover iïj.ml8yan ranyes) on thc

7.3 Gmeral water table is a b u t 20 to c% feet in the

7 04 The soils are fertile and the ??SB 112s Copious

7.5 The tract is also irri,gated tl-iraigh Bist m a b

7.6 The recharge and discharge computntions ta

Demographic trends indicete that the Lndia's

376

c f 1.45 per tbausand per anliuam during 1981-85 the population w m l d rise to 300.millions in the year ZOO0 A.D. i.e. about S5$ increase over the 1371 population. Keeping in view the expected improvement in the standard of living of the people during the intervening period, the food and fibre requirements will increase by abwt 100% of 1371 production. Suck an enormous increase in the production is possible through intensive agriculture and bringing additional areas under irrigation by optima utilization of the water resources (Surface and qround )

of ground waters from shallow as well as deep aquifers. Ground water resource though it gets replenished annually, is not an inexhaustible resource. Ecological respansi bility mkes it incumbent on the planners of ground water development projects that this precious resource: is not exhausted due to over exploitatbn arid is so utilized that it also remakis ava.ilable ïor the yencrstion to come. Therefore aremise potential of ground wa.ter anà its safe yield both from shallower and deep aquifers neads to te assessed as accurately as possible to prepa1.e realistic exploitat ion plms and schemes. This aspect has ben duly recognized and separate state level orgpnizations cmpï-is ing of hydrologists, hydrometeorologist, geologist, agronomist, geoph scist and drilling engineers have been set up

will however take time. N grow more food 1) compaign exploitation of ground water recharge &lance may be planned on the %sis of Safe Yield worked out with the approximations and applicatmn of safety factors suited to each project area.

8.2 Tnis will eventually result in intensified drawels

to carry out deta s led investigationa. These detailed studies However to maIntaln the continuity of

mmmv CES Report of the Irrigation Commissian, 1972, Volume-I, Ministry of Irrigation and irower, New Delhi.

1.

2. Krishnm, M.S.,m Geology of India and Emma 3. T o l m , C.J.,l) GroundWater " . 4, Ehattacharya, R.P. 1) Ground Water supplice, depletion of

water table and penetration of rain water to ground water table in Western Uttar Pradesh ( India )IIo

5. U.S.G.S. Water-supply paper, 1608-G Anplycis of Aquîfcr Tests in the Punjab Region of West Pakistan

6. tJ.s.';.S. :uater supkly papc'r, 1608-G '1 Ground Water Hydrciogy of the Punjab, West Pakistan 1~1th '=mphasiS of ?rcblems caused by Canal Irriggtion II .

377

7.

8. 9.

10 o

11 b"

12

33. 14

15 o.

37 8 STATEMENT I

ITEMS - ISWlhRpI - 1.410

.7ss

b.30

- -

D.310

0.oy

0.27

0.06

&IO<

o .ai

ODs'

o .41

o .Ia!

379

A DRAFT

CROSS DRAF T(1+2+:

1 41 II 9

6SC

7 S2

96

2s

. Il

0.309

o. 132

380

S E\SM\C L \ NE’S RE F LE CTI ON REFRACTI ON

h 8-

TEST WELL LOCATION 8 CONTOUR INTERVAL 02KM DATUM M.s L hLLUV\kL PU\H5 O ?LRYLbRY (SM\\uhL\KS)

381

M A P 15

IMPROVED TECHNIQUES FOR WATER RESOURCE SYSTEMS DESIGN

J R SEXTON

D G JAMIESON

WATER RESOURCES BOARD, READING, ENGLAND

ABSTRACT

Flow data inadequacy can take different forms. One extreme is the complete lack o f any information but the more usual case is insufficient length of record since very long sequences of flow data are required to evaluate the yield and reliability of water- -resource systems with confidence. Using traditional concepts o f failure and reliability, all water-resource systems are being designed on inadequate data with only the degree o f inadequay varying between schemes, The use of simulation as a design technique has necessitated a more rigorous definition o f reliability which accepts the lack of data yet maintains a means of comparing the reliability of different schemes both in terms o f frequency and magnitude of failure, A new definition of reservoir reliability has been used for the hydrological design of the Wash Estuary Storage, a proposed series of pumped-storage reservoirs in south-east England.

RESUMEN

La insuficiencia de datos de flujo puede tomar formas distin- tas. Ocurre el caso extremo de la falta total de información, pero lo más usual es la duración insuficiente de registro puesto que se necesitan cantidades inordenadas de datos de flujo para que se eva- IÚen confianza la eficacia de sistemas de recursos hidráulicos. Em- pleando conceptos tradicionales del fracaso y de la eficacia, todas las instalaciones de recursos de agua se han concebido con datos de flujo inadecuados, con grado de insuficiencia como sola variación entre ellas. El uso de simulacibn como modo de diseñar sistemas com- plejos de recursos de agua exige definición más riguroso de eficacia que mientras acepta la falta de datos de flujo mantiene sin embargo un medio de comparar la eficacia de un proyeqto con otro y en térmi- nos de su frecuencia de ella y en grado de su fracaso. Un concepto de esos -la frecuencia de poTcentaje cumulativo- se ha empleado en el disefio hidrológico Ifel depósito del estuario del Washff, serie de depÖs*itos de reserva a bomba en e l sudeste de Inglaterra,

384

INTRODUCTION

The analysis and study of water resource systems can be conven- iently subdivided into three stages, planning, design and operational. Each stage has its own specific flow data requirements and what maJr be adequate for one stage could well be inadequate for another. planning stage, a large number of possible combin&t&ons of sources are evaluated but not in detail: the requirement for hydrological data is minbal, since the yields of individual sources need only be determined approximately. The most promising combinations of sources are sub- sequently examined in considerably more detail at the design stage. This stage is concerned with aspects such as frequency, probability and reliability all of which make considerable demands in terms of data quantity and quality. records which may have a time increment of a day or more. ational staze, the data requirement emphasis changes from long-term flow records to shorter but more detailed flow records perhaps even on an hourly basis.

At the

The requirement is for long period of flow In the oper-

This paper is concerned with the relationship between the assess-

Flow data can be inadequate in many ways: it may ment of reliability, the definition of failure and flow data inadequacy at the design stage. be that there is no data or Rot enough data, or the wrong data has been collected. Data can be of inadequate quality or have too coarse a time increment between successive values. To sunmiarise, inadequate data is an occupational hazard to all those involved in the hydrological design of water-resource systems. However, with traditional concepts of reliability and what constitutes a failure, the problem of flow data inadequacy will remain for a very long time.

In the planning of water resources for England and Wales, many diverse types of sources such as pumped-storage reservoirs, multi- purpose reservoirs, rivers, aquifers and estuarial storage are being considered. hut as part of a much larger water-resource system. stances the individual yield of the proposed source loses importance since it is the yield of the system as a whole that requires evalua- tion. The increase in the scale of the problem caused by consideration of a water-resource system as a whole has outdated many of the tradi- tional techniques for analysing the performance of a resernoir: some of the implicit assumptions have been made invalie by the complexity of modern water-resource systems, other assumptions have never been valid.

m H O D OF ANALYSIS

&ch proposed source is n? longer considered in isolation In these circum-

.

owing to the complexity of the water-resource systems currently envisaged and the lack of theoretical techniques cspable of analysing such systems, simulation is considered to be the only viable method of analysis. A simulation model of a proposed water-resource system can be constructed by joining appropriate component models of particular types