Center for Environment and Energy Research and Studies (CEERS)
Abstract
Assessment of possible sources that control the groundwater quality was
carried out in the Cauvery deltaic region, India, since domestic and
agricultural water requirements are largely met by groundwater
abstraction. Major ion and bromide contents are high in groundwater in
the coastal wells. Spatial and vertical distributions of ions reveal
that the shallow wells and wells in coastal parts have high chloride,
nitrate, ammonium and phosphate. Groundwater quality assessment was
carried out using the prescribed limits of World Health Organization
and Bureau of Indian Standards which indicates that 55 % of samples are
not fit for drinking. Integrated suitability map for drinking was
created based on the concept that if the water sample exceeds any one
of the standards by World Health Organization or Bureau of Indian
Standards, the well is not fit for drinking. Groundwater quality for
agricultural activities was assessed using electrical conductivity,
sodium adsorption ratio, residual sodium carbonate, United States
salinity laboratory diagram and Food and Agricultural Organization
methods. According to Food and Agricultural Organization, 84 % of
samples are classified as low sodium water and are suitable for all
crops and soils. It was found that the water quality in this area is
affected by improper disposal of waste, sewage/drainage canals near the
wells, irrigation return flow, application of agrochemicals and saline
water intrusion in the coastal region. Further, integrated suitability
map produced in this study will be useful for future groundwater
development and planning in this area. The suitability map needs to be
updated periodically for proper management plan to preserve the
groundwater resource in this region