Rainwater harvesting to augment the groundwater both in quantity and quality is necessary in view of the increasing water crisis in the city and region around it, due to the steep rise in population and the area becoming a concrete jungle, said a professor of Andhra University on the eve of the World Water Day to be observed on Friday.
The United Nations dedicated year 2013 to water cooperation with a view to enhance public awareness and adapt freshwater management techniques. This is instrumental to provide an adequate supply of safe water for household consumption for a healthy life.
Visakhapatnam has become an industrial hub but the act of humans in the indiscriminate and unscientific disposal of waste polluted the land and consequently freshwater became scarce affecting the life of the living and environment. Apart from the pollution caused, it is also observed that seawater entered the inland through the occurrence of rock-fractures near AU Yoga Centre, which is another example of deterioration in groundwater quality, a professor of geology and winner of National Mineral award Nandipati Subba Rao said.
Tanks and streams in and around the city have disappeared due to encroachment of land and the open area has shrunk further due to concrete structures, all leading to very little of rainwater infiltrating into the sub-surface of land.
Quantitatively, infiltration capacity of rainwater into sub-surface reduces by 70 to 80 per cent in urban areas like Visakhapatnam, he says. The inadequate availability of riverwater makes tapping of groundwater resources as the only option for household consumption. Hence the civic authorities have to take a lot of care with regards to lands covered with tanks and streams, and also for keeping adequate land open for infiltration of recharge water. Fresh water should have total dissolved salts less than 500 milligrams per litre; calcium 75 mg/L; magnesium 30 mg/L; sodium 200 mg/L; chloride 250 mg/L; sulphate 150 mg/L; nitrate 45 mg/L; fluoride 1.2 mg/L; and trace elements 0.05 mg/L.
“Water is a shared natural replenishable source for all. Thus increased water cooperation among water stakeholders in all regions for the long-term sustainability of the prospective society is necessary,” Prof. Subba Rao said.