As the sea seeps in

By SNV Sudhir

Visakhapatnam, Sept. 7: An expert study has revealed that groundwater in the coastal areas of the state is slowly turning salty. Unless urgent remedial action is taken, the farmers of the area would face crop failure and attendant financial crisis. The hydro geochemistry study was conducted by a group from the environmental science department of the Gitam University.
As part of it, 81 groundwater samples were collected from 21 places in Nellore, East Godavari, Visakhapatnam, Vizianagaram, and Srikakulam districts. And most of the samples contained salt. One reason for this is the overuse of groundwater. In scientific terms, when freshwater is withdrawn at a faster rate than it can be replenished, the water table drawdown sets in with a resultant decrease in the overall hydrostatic pressure. And when this happens near an ocean shoreline, the saltwater from the sea intrudes into the freshwater aquifer.
Some of the water samples collected were tested and studied at the university labs and others at the National Geographic Research Institute at Hyderabad. "Alarmingly, most of the water samples collected are salty," said Prof. Ch Ramakrishna of Gitam University . "This spells trouble for agricultural activity along the entire coastal area." Not only that, the general populace would also face acute shortage of freshwater. Prof. Ramakrishna said that there were a large number of borewells in Nellore which had resulted in overuse and depletion of groundwater. This resulted in intrusion of salt water.
The situation in Vizag was even worse because of the discharge of polluted industrial wastes into seawater which then creeps into groundwater. "This is causing an environmental ecological imbalance," said Prof. Ramakrishna. "The effluents being discharged into the sea by industries in and around Vizag are not being treated well. The levels of magnesium, sodium and other minerals in the groundwater are also found to be above the required levels.

Vizag becoming Chennai

Visakhapatnam would soon become another Chennai at the rate in which the groundwater in the district is turning salty. Residents of coastal battery near the collectorate, Kota Veedhi, the old post office and the port areas in One Town, Mulakuddu and Nagarapalem besides, parts of Thagarapuvalasa in the rural areas were in distress recently after it was found that the water they drew from their wells tasted salty.
Chennai residents had experienced this over two decades ago following overdrawing of groundwater. At present, people in chennai are unable to extract freshwater from the ground and have to depend on other sources. "We were surprised to get salty water from the well in our backyard instead of freshwater as usual," said Mr Ramu, a resident of coastal battery. "We have never used municipal tap water as the water from our well always tasted good. But all that has changed now."
Experts pointed out that groundwater had been overdrawn in Vizag and there was no scope for recharge. Most people have plastered their compounds with tiles or cement and this prevents rainwater from seeping into the ground and replenishing groundwater.
"There is rapid depletion and deterioration in quantity and quality of groundwater," said Mr D. Bhima Sankar Rao, deputy director of the groundwater department. "Though we have not received any specific complaint about saltwater intrusion, we know that the coastal battery area is affected by this," he further added.
To solve this problem, the groundwater department has been asking local bodies to insist on setting up of recharge structures during construction of commercial buildings, residential complexes and industrial houses. In most places, once saltwater intrusion takes place, it requires great efforts to bring things back to normal.
"However, Vizag is lucky since it is surrounded by hills which protect groundwater," said the official. "City residents need to adopt methods of artificial recharge such as rainwater harvesting, recharge pits or recharge wells."