Chennai, Jul 12 (IANS): The Tamil Nadu Water Resources Department has floated tenders for the restoration of the twin lakes in Chennai and the work is likely to commence by August.

The twin lakes, commonly known as Retteri, will be desilted and cleared of encroachments.

A Department official told IANS that an invasive species of water hyacinth which reduces oxygen supply and creates breathing difficulty for fish has occupied a large portion of the lakes.

The water hyacinth, according to the official, also act as breeding ground for mosquitos.

The twin water bodies comprise the Madhavaram inlet channel and Manali lake and according to Department officials, an amount of Rs 44 crore have been sanctioned for the restoration work.

According to officials, a portion of the lake is occupied by 40 illegal structures and these have to be removed first.

On the western side, the Department will construct a wall for a distance of 3 km and to prevent garbage dumping.

Towards the eastern side, pillars will be installed and a fence erected.

The water level in the twin water bodies is presently 32 million cubic feet and the Department will dig deep to increase the holding capacity to 45.13 mcft.

One million liters of water a daywas pumped from the twin lakes by the Metrowater to its Kolathur plant and from their water supplied to the houses in the vicinity of the lake.

However, this is not being done due to illegal encroachments and dumping of garbage in the lake.

Sources in the Department told IANS that after the restoration work is completed water will again be pumped to the Kolathur plant and after treatment supplied to locals in the vicinity of the two lakes.