In India Groundwater is the major source to meet water requirement for agriculture, drinking, domestic and all other uses. Annul ground water draft in India was estimated as 253 bcm in year 2013 out of this agriculture sector including livestock consumed about 90% (228 bcm) of total ground water draft and about 10% (25 bcm) used for domestic and industrial purposes.
As the agriculture food products and drinking water are directly affect the health of human being, it is crucial to monitor and manage the ground water quality. A NITI Aayog report (June 2018) has raised alarming concerns for the water situation in India, as the report cited data ranking India at 120th position among 122 countries in the water quality index.
Ground Water Quality
Indian Sub- Continent is endowed with diverse geological formations from oldest Achaeans to recent alluviums and characterized by varying climatic conditions in different parts of the country. The natural chemical content of ground water is influenced by depth of the soils and sub-surface geological formations through which ground water remains in contact.
Ground water in major parts of the country is potable. Although some water quality issues are reported from isolated pockets from various parts of the country. Higher level of the constituents like Arsenic, Fluoride, Iron, Nitrate and Salinity in ground water is due to the natural geological phenomena and classified as geogenic contaminates. The quality in deeper aquifers also varies from place to place and is generally found suitable for common uses. There is salinity problem in the coastal tracts. Manmade activities like mining activity, disposal of industrial wastes and untreated domestic wastes are responsible for contamination like nitrate and heavy metal.
Ground water quality monitoring
Ground water quality monitoring is an effort to obtain information on chemical and bacteriological quality.
- Central Ground Water Board (CGWB): The chemical quality is being monitored once in a year through observation wells located in different hydrogeological units all over the country, parameters tested are Arsenic, Fluoride, Nitrate and Electric conductivity. CGWB is monitoring 23,125 observation stations for water quality along the country.
- Ministry of Drinking Water and Sanitation: The chemical and bacteriological quality of drinking water source (ground water) in rural area is being monitored through state water supply departments with systematic laboratory network (more than 2000 laboratories) from state to block level and each laboratory have to test 3600 water samples per year; total capacity of laboratories is to test 79,05,600 water samples per year. Parameters tested are Arsenic, Fluoride, Nitrate, Salinity, Iron and Bacteriological. Total 63,51,174 schemes / spot sources are being monitored circularly.