BENGALURU: Across the state, insufficient rainfall and reservoirs drying up have left many in despair. As a result, more borewells have cropped up across the state.
The excessive drilling for borewells have depleted ground water tables, forcing people to drill further deep. This has further resulted in people drawing water that contains harmful metals and chemical compounds.
Officials at the Department of Mines and Geology have estimated 25 lakh borewells across the state, with one lakh being added every year on an average. This has led to water being drawn before the water table is replenished. Below a certain depth, the water contains iron, arsenic, flourides, nitrates, magnesium, zinc etc.
According to Captain S Raja Rao, a water expert and former Chief Engineer, State Water Resource Development Organisation (SWRDO), said water below a certain depth is not fit for consumption as it contains additional iron, arsenic, flourides, nitrates and other chemicals which are harmful to our health.
Captain Rao said consuming flourides will cause chlorosis in children, adults and even animals.
“Teeth and gums will be affected with teeth turning darker. Consuming nitrates is known to be a reason for birth of blue babies. Excess nitrates in our diet will reduce oxygen-carrying capacity of blood that will eventually affect the baby’s heart. Long-term exposure to iron in water will cause joint pain and other ailments.”
Captain Rao said that about 20 years ago, water would be found at just 60 feet.
The water level went further down to 400 feet 10 years back. It has now crossed 1,000 feet, he said.
“This summer, one will have to depend on packaged water bottle as there’s no other option,” he said.
Vishwanath Srikantaiah, a water expert, said as per the sample survey conducted by the Department of Mines and Geology a few years ago, 65 per cent of borewell water samples were found to be contaminated with nitrate. The percentage of nitrates in borewell water varies from place to place, valley to valley.
“Boiling water will not help as chemicals will remain. Chemicals like nitrates will have serious effects on health of children and elderly,” he said. He pointed out it will not cause much harm to agriculture.
Speaking to Express, a senior BWSSB engineer blamed the Metro construction. “When BMRCL constructed foundation pillars and underground tunnels, it disturbed ground water channels. The water table depleted with more people drilling borewells.
After Bengaluru Mahanagara Palike became Bruhat Bengaluru Mahanagara Palike, more residents came under BBMP and they are largely dependent on borewell water.”