GROUND WATER SCENARIO IN UTTAR PRADESH

              Groundwater is a dependable resource that is contained and transmitted through the interstices in rock materials below the earth surface. It is considered and rather used to be a cheap and easily extractable commodity. However, with a rapid growth of population and all round development, there is incessant pressure on the ground water withdrawal resulting compulsive awakening in terms of both the quality and quantity. If the present trend of the increasing demand remains incontrollable, the resource may be as strategic as are the minerals and the petroleum resources. Though in contrast to these, the resource of groundwater as a part of hydrologic cycle is replenishable.

              Central Ground Water Board under the Ministry of Water Resources, Government of India is the Apex body in the country to deal with all the aspects of groundwater.

              The geographical area of U.P. is 2,40,927 and population 16,60,52,859 (2001 census). Uttar Pradesh being the most populous state of the country faces problems like decline in water level, water logging conditions and ground water pollution. Therefore, it is imperative to plan the development of ground water in more scientific and planned manner for its economic utilisation without creating any environmental hazard.

HYDROGEOLOGICAL SET UP

              The hydrogeomorphic characters of various units of U.P. are discussed briefly in following paragraphs.

Bhabher and Tarai

              A thin stretch of Bhabher occurs south of Sub-Himalayan zone. To the south of Bhabher, Tarai belt of variable width (8-15 km) runs from north-west to south-east. Here, swampy conditions are found due to shallow ground water and spring line with fine-grained fluvial sediments. The ground water occurs under unconfined state in shallow zone, while the deeper aquifers below 50m depth are under confinement. Auto flow conditions are common in the belt.

Central Ganga Plain

              This hydrogeological unit is confined between Tarai zone in the north and marginal alluvial plain in the south. The Ganga Plain is characterised by low relief and enormous fluvial features. The general slope of the zone is to the south in upper reaches and south-east in the lower reaches. The average slope ranges between 15 to 50 cm/km. The shifting of rivers has been a common phenomenon. The rivers have degraded their own plain carving a new one. The extensive high land between the two rivers forms the older alluvial plains while the younger alluvial plain are confined to present day drainage network. Extensive exploration studies have indicated the presence of four aquifer groups within a depth of 700m below ground. The first shallow phreatic aquifer, within 50m depth is being utilised by the marginal farmers to construct tubewells / borewells. The ground water is present under confined to semi-confined state in shallow aquifer while in the deeper aquifer, it occurs under confined state. The second aquifer, which occurs between the depth of 50 to 200m is being extensively exploited to fulfill the irrigational need.

Marginal Alluvial Plain

              All along the northern border of southern Plateau Region lies the marginal alluvial plain, spread over in parts of Mathura, Agra, Etawah, Jalaun, Hamirpur, Banda, Allahabad and Mirzapur district. This zone constitutes the alluvial sediments brought down by northerly flowing rivers originating from the Plateau Region. The thickness of marginal alluvial plain is variable ranging between 50 and 200m. It comprises admixture of Kankar and clay with sand and gravel lenses. Ground water occurs under water table and semi-confined conditions. The marginal alluvial aquifer is capable of yielding 60-1500 lpm of fresh water at a draw down of 6 to 15m. The ground water quality poses a problem in localised patches.

Southern Plateau Region

              The region occupies extreme southern part of the state and is characterised by table land punctuated with variety of land forms. The region is underlain mostly by Vindhyan sediments. The Precambrian crystallines are exposed over Betwa Basin.

              The ground water mostly occurs in the secondary porosity of hard rocks under unconfined state. The alluvial sediments occupy the existing valleys. The ground water in alluvial sediments occurs under unconfined state. Ground water prospects are rather low.

GROUND WATER LEVELS

              Depth to water in any area is of great significance in deciding drilling depths, selection of pumping devices, crops to be grown and deciding areas for ground water storage / artificial recharge. The indiscriminate exploitation of ground water has led to depletion of storage and lowering of water levels in many parts on one hand and rise in water levels to critical limits on the other hand in parts of certain Canal Command areas. The management of ground water storage thus becomes essential to avoid any adverse impact. The Central Ground Water Board have established more than 1200 key observation wells as permanent hydrograph stations to monitor both the ground water quality and change in storage. The behavior of water table is observed four times i.e. January, May, August and November every year.

              The water levels in Uttar Pradesh show a wide variation from less than 2 mbgl to more than 30 mbgl. In Bhabher area, the depth to water level varies from 8 to 35 mbgl., while in Tarai, it ranges from less than 2 to 10 mbgl. The central and eastern parts of the state shows a wider ranges of water levels varying from less than 2 mbgl as observed in Sharda Sahayak Canal Command area to more than 20 mbgl along the natural levees formed on either side of river Ganga. The water levels in southern parts (Plateau Region) vary from 2 to 30 mbgl. The deepest water levels are encountered in the ravinous tracts along the Yamuna and Betwa rivers in Hamirpur, Jalaun, Banda, Allahabad and Jhansi districts.

              The western parts of Uttar Pradesh are characterised by deeper water levels ranging from 8 to more than 30 mbgl, as noticed in most of the districts. The water levels have shown significant declining trends over the last two decades due to over exploitation of the ground water resource.

WATER LEVEL TRENDS

              Over exploitation of ground water, especially in western parts of Uttar Pradesh has led to decline in water levels over the past few years. The State Ground Water Department has categorised the blocks on the basis of level of development of ground water and water level trends. Out of 22 over exploited and critical blocks, 19 blocks are located in western parts of the state in districts of Agra, Aligarh, Baghpat, Bareilly, Badaun, Etah, Farrukhabad, Ferozabad, Jyotibaphulenagar, Moradabad and Saharanpur. The water level declining trends in these blocks are about 30 to 55 cm/year in either pre or post monsoon period or both. Out of 53 semi-critical blocks, 28 are located in western U.P. On the other hand, in the Canal Command areas, the water logging and related problems like salinization & degradation of soils are posing a threat.

GROUND WATER RESOURCE POTENTIAL

              As per the National Water Policy, development of ground water resources is to be limited to utilisation of the renewable part of the naturally occurring ground water available in sub-surface domain. The present development policy, obviously forbids utilisation of the secular reserve to prevent ground water mining. Precise assessment of replenishable ground water resources and its development in terms of area which can be irrigated in the framework of land availability, cropping pattern, etc. is, therefore, key to our plans to develop ground water resources for various uses. The complexities of processes governing occurrence and movement of ground water make the problem of ground water assessment somewhat difficult, as not only vast volume of data is required to be collected but also many disciplines of science have to be involved in a co-ordinated manner.

              In India, the efforts in this direction were initiated immediately in post-independence era and the approach and methodologies utilised since then have undergone gradual changes based on the refinement of our understanding in the field of ground water. This in fact will be a continuous process as ground water is a dynamic resource and science is in continuous search for better understanding. Based on the developments in science and situation, the Board in consultation with State and other Organisations would continue to update these figures.

              As a joint venture of the Central Ground Water Board and the Ground Water Department, U.P. have estimated replenishable ground water potential on districtwise basis, based on GEC 1997 Methodology and the estimates for U.P. (alluvial area).

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