New Delhi, Sep 16 (PTI) The cost of rehabilitating outdated barrels that carry 115 million gallons of wastewater a day from south and central Delhi to the Okhla sewage treatment plant has been cut by over 90 percent, thereby saving nearly Rs 600 crore, officials said on Thursday.

These barrels run parallel to each other for 15 kilometers and carry wastewater from five sewage pumping stations – Kilokari, Ring Road, Andrew Ganj, East of Kailash and Pragati Vihar – and four major sewer lines – Modi Mill, Tuglakabad, Kalkaji Trunk and Batla House, they said Leakages lead to reduction in their carrying capacity.

"The Delhi government had earlier approved Rs 662 crore for rehabilitating the barrels as these have exhausted their usual life," a statement said.

After the intervention of Water Minister Satyendar Jain, the cost of this project has been reduced by more than 90 percent. Now, the work will be completed within Rs 60 crore in two years, it said.

One of the existing conduits was made by the British in 1938, while two other barrels were constructed in 1956 and 1985.

Jain directed officials to lay down a new pipeline of 2,200 mm diameter made of high-density polyethylene material parallel to the existing conduits on priority to provide immediate relief to the area.

It will be followed by rehabilitation of the oldest barrel within four months. The rehabilitation of the second barrel (constructed in 1956) and the cleaning of the third conduit (made in 1985) will be completed within two years.