Environmental impacts of

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Environmental impacts of groundwater
intensification in India
Sunderrajan Krishnan Trishikhi
Raychoudhary Chaitali Purohit Ankit Patel
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Definition 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
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Which 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

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Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
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Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
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Nation-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
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Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
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Studies 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

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Studies in four regions
Bist-Doab
North Gujarat
Coastal WB, N. Orissa
Noyyal sub-basin of Cauvery
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Studies 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
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Studies 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

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Building blocks of study
Region based (4 regions)
Nation-wide analysis (at district level)
Issue Based (2 issues)
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Issue 1 Coastal salinity of groundwater
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Issue 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
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In 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
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Issue 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