The current sources of water supply for CMWSSB are wholly dependent on the vagaries of the monsoon in Chennai, and therefore may not provide a reliable and assured supply during a failure of the monsoon. Further, there was also a need of a source independent of the monsoon, which will also help in drought proofing the city. Hence the board proposed to implement a Sea Water Desalination Project on a Design, Build, Own, Operate and Transfer (DBOOT) basis, as a drought-proofing measure - to provide a reliable source of water supply to Chennai city, and also to bridge the gap between demand and availability.
Tenders were finalized for setting up a 100 mld sea water desalination plant with M/s. IVRCL Infrastructure & Projects Ltd., in a joint venture with M/s. BEFESA. A bulk water purchase agreement was entered between CMWSSB and Chennai Water Desalination Limited to construct the plant at the site leased to the company by the board. The scope of the project includes all detailed design, engineering, financing, procurement, construction, completion, O&M of the facility in accordance with technical requirements, performance standards and prudent utility practices, for an agreement period of 25 years.

CMWSSB guaranteed a take-or-pay at water minimum off-take for each operating year at the water dispatch point (UGT) throughout the operating period. The company shall not supply product water to any third party during the term of the agreement. The charges payable by the board to the company for product water will be the water capacity charges (amount charged, collected etc.), and the water variable charges (chemicals, power and other O&M costs). The company has to supply 15 mld of product water in phase I, i. e., within 12 months from the effective date, and 100 mld in phase II i.e., within 15 months from the effective date. Construction work of the plant is under progress, and at present, 50% of the works has been completed. Laying of pipelines and allied works for the distribution of product water to Chennai city is under progress.

• After commissioning of the plant, 100 mld of product water is ensured to Chennai city.
• The water supply from the plant will be available continuously even during a drought situation, without any interruption.
• This project will be a permanent source of water supply for Chennai city.
• It minimizes extraction of sub-soil water by the consumers and industries, which in turn minimizes sea water intrusion in the coastal belt. Thus, ground water potential will be retained.

This can be implemented in modules of similar capacities depending on the requirement/demand of drinking water, and will also be a model plant to serve data for future projects in this country.

For further details, contact:
Mr. Shiv Das Meena, IAS
Managing Director
CMWSSB