Expert against building desalination plant in city

Coastal reservoir too opposed; ‘land-based storage best alternative’

With the proposal of a petrochemical company to set up a desalination plant in the city now pending before the State government, a senior professor of the Indian Institute of Science (IISc), Bengaluru, has said that such plants would endanger marine life.

According to T.G. Sitharam, professor in civil engineering and KSIIDC (Karnataka State Industrial Investment Development Corporation) chair professor in the area of energy and mechanical sciences, IISc, setting up a desalination plant is highly expensive. In addition, after desalination, residues discharged in deep sea would threaten marine life due to high salt content in about one-kilometre radius.

The petrochemical company in Mangaluru has sought 10 acres of land in the Tannirbavi area to set up the 50 MLD (million litres a day) capacity plant and the proposal is now before the Karnataka Udyog Mitra.

Mr. Sitharam favoured building a floodwater coastal reservoir in Mangaluru to meet both industrial and drinking water needs by storing floodwater between June and September.

According to him, with this, there would be no harm to any of the river basins and there would be no alteration of the river course.

The reservoir could be built outside the mouth of the Netravathi in the Arabian Sea.

The professor said that when a coastal reservoir is built, there woudl be no need to rehabilitate people. Also, it would not result in submergence of farmland and there would be no loss of forest cover. Intrusion of saline water into the coastal wells could be reduced.

He said that dredging from the reservoir stored with fresh water would provide sand for construction and coastal erosion could be minimised.

Not practical

Meanwhile, opposing building a coastal reservoir in the city, S.G. Mayya, a former professor of applied mechanics and hydraulics, National Institute of Technology, Karnataka (NIT-K), Surathkal, said that it was not feasible as the Arabian Sea was not a bay. The Netravathi carried huge amount of silt during the rainy season and building a reservoir would lead to another environmental issue and it would result in erosion of the coastline. According to Mr. Mayya, land-based water storage was the best alternative to augment water for the future.