Title: Environmental impacts of
1Environmental impacts of groundwater
intensification in India
Sunderrajan Krishnan Trishikhi
Raychoudhary Chaitali Purohit Ankit Patel
2Definition of problem
Any disturbance from the natural regime of
groundwater flows or geochemistry caused
by intensification of groundwater use that
results in significant impact on environment
and on humans Challenges To define natural
regime To isolate role of GW use on the impact,
eg. coastal salinity
3Which issues are being studied
- Fall in water tables and rise in water tables
regionally - Highly fluctuating water table
- Quality problems emanating from exploitation eg.
salinity in coastal areas, increasing
mineralization of deeper aquifers, release of
geogenic heavy metals associated with
exploitation - Quality problems due to use of poor quality
water for irrigation - Related surface water issues eg. tanks that
recharge aquifers, being in disuse , partly due
to gw use
4Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
5Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
6Nation-wide analysis at district level
- Objectives
- To delineate zones of GW vulnerabilty using
different criterion - Volumetric information GW recharge, GW use for
various purposes Proportion GW used for
irrigation - b) Depth to Groundwater Table Median depth to
water table Median fluctuation of water table - c) Impact of well interference well density and
hydrogeology together impacting well interference
Overlap these zones to mark regions of varying
vulnerablity
7Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
8Studies in four regions
- - Bist-Doab of Punjab overexploitation and
agro-pollution groundwater balance and trend
analysis - North Gujarat overexploitation, Fluoride,
Salinity, urban exploitation and pollution - Coastal West Bengal and Orissa saline water
intrusion and urban subsidence of land - Central Tamil Nadu Noyyal sub-basin of Cauvery
overexploitation, pollution, demand from urban
areas
9Studies in four regions
Bist-Doab
North Gujarat
Coastal WB, N. Orissa
Noyyal sub-basin of Cauvery
10Studies in four regions
Objectives Detailed characterization of
environmental impacts of groundwater use in the
region Extrapolation to parts of the country
that are similar to this region
Eg. North Gujarat overexploitation of aquifers
Fluoride contamination Urban demand of
groundwater from Ahmedabad area Coastal and
inland salinity of groundwater Can be
extrapolated to parts of Rajasthan
11Studies in four regions
- Fresh studies
- - Collecting long-term groundwater hydrographs
from - Bist-Doab for better hold on groundwater balance
- Collaborative work with WTC, Coimbatore on
groundwater exploitation in Noyyal basin
12Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
13Issue 1 Coastal salinity of groundwater
14Issue 1 Coastal salinity of groundwater
Compiling the conceptual picture of coastal
salinity across the coast Information on
Geomorphology, Hydrogeology, Tidal patterns,
Observed salinity data Important
regions Gujarat (Kutch, Saurashtra, South
Gujarat) Tamil Nadu (North) Central Andhra
Pradesh Orissa (Central to North) West Bengal
15In summary
Combining analysis of 4 regions with A
nation-wide district level analysis and 2 issues
To arrive at constraints for groundwater
intensification And limits to expansion of area
irrigated by naturally recharged groundwater
16Issue 2 Urban groundwater exploitation
- Patterns of groundwater use in urban areas
- Major growth of urban areas is happening in
- 1,00,000 1 million population
- Most of these cities are highly dependant on
groundwater - much more than million cities
- The locus of future GW demand in urban areas
will be these towns - Main data proportion dependence of urban area on
GW