IISc professor moots plan to save floodwater

'Mangaluru has excess water enough for entire Karnataka'

 “If water can be managed and stored scientifically, there will be excess water in Mangaluru which can be supplied not only to the entire Karnataka state, but also to the neighbouring states.”

Prof T G Sitharam, professor in civil engineering at IISc, Bengaluru, made a presentation before reporters on ‘Floodwater Coastal Reservoir in the Arabian Sea,’ an initiation of B R Shetty, BRS Recreation Limited, on Tuesday.

The professor said that from Nethravathi River alone, more than 120 TMC of floodwater runs into the Arabian sea in just four months between June and September, every year. Stating that the total requirement of water for entire Karnataka is about 90 TMC (considering the 6-crore population and each person requiring 150 litres of water a day), Prof Sitharam said that Nethravathi River alone can supply drinking water to every single house in Karnataka. “But the irony is that Mangaluru is facing drinking water shortage during summer,” he rued.

Sea-based reservoir

Proposing a new sea-based reservoir technology to impound floodwater during monsoon and store it in coastal area within the sea itself by constructing a reservoir using sea walls, he said the excess floodwater will still flow to the ocean carrying the salts without any hindrance or obstacles.

Listing out a number of benefits of sea-based reservoirs, he said that only floodwater is captured and there will be no damage to the environment, river course or marine life. There will be no disturbance to the habitats, villages or towns and there will be opportunity to breed freshwater fish in the reservoir. In addition, solar power can be generated on the side walls of the reservoir and using floating solar panels in shallow waters, besides promoting water sports and increasing ground water table.

When asked, he said that the reservoir is much cheaper (Rs 2 a kilo litre) when compared to desalination plants (approximately Rs 75 a kilo litre) or interlinking of rivers. Mangaluru may require approximately Rs 2,000 crore to construct a reservoir with a storage capacity of one billion cubic metres while it may cost Rs 8,000 crore for the same in the case of desalination plants. However, to construct a reservoir that could store 25 TMC of water, it may require Rs 3,500 crore and 7 + 7 km space in the sea front.

He also said that he has submitted a proposal in this regard to Chief Minister Siddaramaiah.

To a query on Yettinahole project, he said that it will not benefit anyone.