Mumbai's Manori Desalination Project Moves Forward with CRZ Clearance Recommendation
The ambitious desalination project planned for Manori in Mumbai has taken a significant step forward. The Maharashtra Coastal Zone Management Authority (MCZMA) has recommended the project for Coastal Regulation Zone (CRZ) clearance, albeit with specific environmental conditions attached.
Project Details and Clearance Process
During a meeting held on March 25, the MCZMA granted its recommendation and forwarded the project file to the Union Environment Ministry for final approval. The Brihanmumbai Municipal Corporation (BMC) is spearheading this initiative to establish a 400 million liters per day (MLD) seawater desalination facility at Manori. The project will be implemented in two phases, with the first phase targeting 200 MLD capacity.
An official involved in the project emphasized that with Mumbai's continuously growing population and escalating water demands, desalination represents one of the few viable long-term solutions to address water scarcity in the suburban regions. According to project documentation, the proposed site spans multiple CRZ categories, including CRZ-I(B), CRZ-III, and CRZ-IV, with a minor portion falling within a 50-meter mangrove buffer zone.
Technical Specifications and Environmental Considerations
The desalination plant will employ a sophisticated two-stage reverse osmosis process. This involves seawater reverse osmosis (SWRO) followed by brackish water reverse osmosis (BWRO), complemented by an energy recovery system and comprehensive cleaning infrastructure. The marine component of the project includes laying intake and outfall pipelines, installing diffuser systems on the seabed, and discharging treated brine back into the sea.
While recommending the project, the MCZMA imposed several crucial conditions to mitigate environmental impact. These include strict adherence to all CRZ regulations, protection of existing mangrove ecosystems, ensuring tidal flow remains unobstructed during pipeline installation, and implementing robust measures to manage brine discharge effectively. Additionally, the BMC has been instructed to ensure local fishing activities remain unaffected and that all construction debris is scientifically processed outside CRZ areas.
Environmental Impact Assessment and Community Concerns
The Environment Impact Assessment (EIA) report identified potential impacts on marine ecosystems, particularly from brine discharge. However, the report indicated that with properly designed diffuser systems, the increase in salinity would be limited to slightly above ambient seawater levels, thereby minimizing ecological damage within a confined mixing zone.
Experts within the authority expressed concerns regarding potential effects on marine life and fishing activities. In response, the BMC detailed mitigation measures incorporated into the project design. These include multiple diffuser ports for rapid dilution, careful selection of discharge locations, and maintaining adequate distance between intake and outfall points to prevent recirculation. Importantly, following consultations with local fishing communities, no desalination activities are proposed within the Manori creek, which serves as a key fishing zone.
This development marks a crucial milestone in Mumbai's efforts to secure sustainable water sources for its expanding population while balancing environmental protection and community interests.
