GROUND WATER DEPLETION LUCKNOW CITY (DEC 2017)
SUMAIRA SIDDIQUI URBAN PLANNER CMMU
ENVIRONMENTAL ISSUES
CITY
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
CHALLENGE : ALARMING FALL OF GROUND WATER Survey by state groundwater department, pre and post-monsoon in 2012, 2013 and 2014 paints a bleak picture for Lucknow which has water table going down by 80cm to 1 m every year. What augments the worry is that government as well as city residents have yet to do the needful. In Lucknow city, river Gomti has been the main source for drinking water, but now 70% of municipal water supplies are dependent on ground water, making it a predominant source for city's water supplies. This clearly reflects the vital position ground water has attained in urban water system, despite the fact that this resource is depleting fast within the transforming concrete environment of Lucknow. URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
CHALLENGE : ALARMING FALL OF GROUND WATER The city is located on alluvial aquifers of Indo-Gangetic plain, and stretches across both banks of the Gomti River which is an entirely lowland river naturally dependent on groundwater discharge for its dry-weather flow. With urbanization and unchecked private tube-well borings, heavy pumpage / continuous abstraction of ground water resources has caused wide spread depletion of aquifers and as a result ground water levels have gone down drastically to almost unsustainable levels, from where it seems very difficult that the depleted conditions of ground water could ever improve.
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
CHALLENGE : ALARMING FALL OF GROUND WATER Between Pre monsoon, 2014 & 2015 that is in one year, relatively much higher decline in ground water levels has been recorded, as shown in the following graph/table
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
CHALLENGE : ALARMING FALL OF GROUND WATER The cross section shows of Lucknow City clearly shows that since 1970 how ground water has depleted. The graph shows a "Trough" like situation that has developed in the Lucknow city as depicted by ground water level of 2015.
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
GROUND WATER ZONES IN PRE MON SOON PERIOD 2006-2014 2006
2014
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
GROUND WATER ZONES IN PRE MON SOON PERIOD 2006-2015 Pre-monsoon and Post-monsoon water level data indicates that deeper ground water zones in the depth range of 25-35 mbgl and beyond 35 mbgl have significantly increased since 2006, which clearly indicates the adverse impact of overexploitation, as aquifers are continuously depleting and the water levels are declining to alarming levels, which has resulted in low yields & failures of tube wells.
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
GROUND WATER ZONES IN POST MON SOON PERIOD 2006-2014 2006
2014
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
GROUND WATER ZONES IN POST MONSOON PERIOD 2006-2014 In post monsoon period, deep ground water levels i.e. beyond 25 mbgl were covering only 10% area of the city during post-monsoon 2006, but within a span of 8 years only i.e. up to post monsoon 2014, this zone has expanded to more than 40 percent of the city.
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
CRITICAL AREAS- DEPLTION FROM PRE MONSOON 2006-2014 Some locations are showing relatively much faster decline that are located in Gomtinagar, Lalbagh, HAL, Puraniya, Alambagh, Naubasta, Jail Road, Triveninagar, Maunibaba, where more than 5 metres of decline has been recorded in both the seasons within a span of 08 years only. URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
CRITICAL AREAS- DEPLTION FROM POST MONSOON 2006-2014 Some locations are showing relatively much faster decline that are located in Gomtinagar, Lalbagh, HAL, Puraniya, Alambagh, Naubasta, Jail Road, Triveninagar, Maunibaba, where more than 5 metres of decline has been recorded in both the seasons within a span of 08 years only. URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
AQUIFIER GROUP IN LUCKNOW In Lucknow city, as per the extensive exploration carried-out by CGWB down to the depth of 750 mbgl, 04 Aquifer Groups, each separated by 5 to 10 m thick clays, are distinguishable. Since last 2 decades, the city is witnessing indiscriminate exploitation o f g r o u n d w a t e r a n d s u c h abstractions have reached to a point where the geoscientists have projected possible threat of landsubsidence in some prominent localities of the city in next 10-20 years. The top Aquifer Group (<150mbgl) of the city is presently under HIGH STRESS. The granular zone of this dynamic aquifer is gradually drying up, causing almost irreversible damage to ground water domain of this capital city of the state. URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
AQUIFIER DISPOSITION OF LUCKNOW CITY
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
REASONS FOR GROUND WATER DEPLETION
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
REASONS FOR GROUND WATER DEPLETION Urbanization & Expansion leading to Rise in demand The trend of ground water exploitation in Lucknow shows continuous rise in resource withdrawals. Construction of drinking water tube wells to meet water demand of this growing urban agglomerate had started in early 70's and by 1985 about 70 tube wells were operating. Now, this number of tube wells, under the control of Lucknow Jalkal, has gone up to 672 (relative increase almost 9.5 times). 2015 Moreover, the 2025 demand prediction for Lucknow City requires a gross available supply of 810 Ml/d (before leakage losses are deducted), which would imply further stress on local groundwater supply.
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
REASONS FOR GROUND WATER DEPLETION Rise in Private Wells & Domestic Borings Apart from city's municipal water supply, the residents possess mindset to have alternative & secured water supplies. As a result city has mushroomed with innumerable private tube wells/ domestic borings to an extent which has led to intensive & unregulated extractions, but there is no realistic estimate of such unregulated withdrawals which are responsible for the present day ground water crisis. As per adhoc estimates, the possible ground water withdrawals in the city from both the municipal & private systems are extremely high which may be tentatively taken as 750 million liters per day (MLD) or more.
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
REASONS FOR GROUND WATER DEPLETION Heavy Use of water at Construction Sites City is growing with large and large scale construction projects are going on to cater to cityâ&#x20AC;&#x2122;s residential needs. These construction sites uses heavy pumpage of water from private borings and wells for their construction activity, which results in fall of water levels at alarming rate. Data Recorded by Piezometer at WALMI Telibagh clearly explains this phenomenon.
The data recorded in the above piezometer indicates an extremely grave situation, as ground water level has declined alarmingly by 6.0 m between 2012 and 2015. This rapid depletion may be attributed to large scale housing constructions going on in Vrindavan colony as well as heavy pumping going in the area. URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
IMPACTS OF DECLINE
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
IMPACTS OF DECLINE • Tube well yields have reduced significantly. Data shows that in Municipal tube well yields have reduced from 1500 LPM in 1970’s to 600- 800 L PM cu rren tl y. T h i s i s d i rect manifestation of depleting aquifers & water level lowering. • The declining ground water levels have changed the condition of Gomti River from effluent (gaining flow from natural ground water discharge) to influent (losing flow to ground water infiltration). • Depression/Hydrogeological Trough has developed within the ground water regime of the city due to extensive ground water withdrawals and subsequent lowering of water levels. (This is supported by the fact that in the peripheral region, water level decline is relatively low to moderate). URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
INTERVENTIONS NEEDED
URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY
INTERVENTIONS NEEDED A separate long term & effective Integrated Water Resource Management Plan should be prepared for implementation, envisaging suitable interventions for a more harmonized conjunctive use of surface and ground water Strict measures supported by public awareness campaigns, are required to check undesirable wastage of drinking water especially in ground water based supply/ distribution systems under water supply network. Excessive withdrawal from top aquifers (<150mbgl) should be adequately reduced & regulated through a regulatory provision. Further, ground water extractions shall be done from deeper aquifer group (aquifer group III) to restrain pumping from top aquifer group. Studies suggest that the peri-urban region of Lucknow city on LucknowSitapur road and in south Lucknow envisages prolific aquifers, which can be systematically exploited to supplement cityâ&#x20AC;&#x2122;s water supply. Existing private tube wells within the city area need to be checked and controlled systematically. Also Rain Water Harvesting/Recharge is neither the only hope and nor the end in rejuvenating the fast depleting resource- Hence, a thoughtful management process needs to be initiated. URBAN PROBLEMS AND PERSPECTIVES: DEPLETION OF GROUND WATER
LUCKNOW CITY