The Expert Appraisal Committee for Projects related to Coastal Regulation Zone (CRZ) of the Union Ministry of Environment, Forest and Climate Change has recommended CRZ clearance to the State’s first reverse osmosis-based seawater desalination plant proposed by Mangalore Refinery and Petrochemicals Ltd. (MRPL).
Headed by Deepak Arun Apte, the committee in its 207th meeting on January 25 said that the clearance was subject to MRPL ensuring temporary structures installed for laying pipelines for the 70 million litre per day (MLD)-capacity plant are removed within one month of completing the work.
Solid waste should be treated and disposed of as per Solid Waste Management Rules 2016, the committee said, while observing that the plant was a necessity and the likely CRZ ramifications were minimal confined to the construction period. Confirming having received the CRZ clearance, MRPL Managing Director M. Venkatesh told The Hindu that in anticipation of Consent for Establishment from Karnataka State Pollution Board (KSPCB), the company has started all preparatory work. The mechanical completion should be achieved by August 2020, he noted.
Chennai-based Indian Multinational Company VA Tech Wabag Ltd., which has provided the drinking water desalination plant for Chennai and similar plants world-wide, has bagged the contract for ₹ 595 crore. The contractor would also operate and maintain the plant for 10 years coming up on NMPT’s 13-acre leased land at Tannirbhavi.
The plant, producing industrial quality fresh water, would considerably reduce MRPL’s dependence on the Netravathi to ensure that the existing facilities and expansions would run without hitch even during summer water rationing, he said.
The committee said that the initial capacity of the plant would be 30 MLD (six million gallons per day), while it can be augmented up to 70 MLD (15 MGD).
MRPL, at present, uses about 13 to 14 MGD water — 8 MGD from the Netravathi, 2 MGD in-house recycled water, 4 MGD treated city’s domestic sewage from Mangalore Special Economic Zone and rainwater harvested within the premises.
When functioning to the full capacity, the plant requires 187 MLD of seawater, of which 117 MLD would be dumped back as brine reject. While the intake head would be located 950 m from the shore, the outfall defuser would be 1,050 m away. Both these HDPE pipelines would be buried 2 m below the seabed.