4.2.18 (HL)—Freshwater production impacts

Desalination trades water scarcity for intake, energy, brine and chemical impacts; evaluate the whole chain, not output alone.

Intakes can injure organisms, pumps create noise, concentrated brine and treatment chemicals can damage receiving waters, and fossil-fuelled energy adds air pollution and greenhouse-gas emissions, as in much UAE desalination. Heavy coastal pumping or freshwater abstraction can lower aquifer pressure and allow saline intrusion. Renewable electricity reduces operational emissions but not intake, brine or aquifer impacts.

A reverse-osmosis plant powered by renewables still needs brine dispersion and intake safeguards; one mitigation does not solve every impact.

Brine impacts can be reduced through controlled dilution, dispersion and chemical management, while aquifers require abstraction limits and salinity monitoring; mitigation reduces rather than eliminates the footprint.

‘Low-carbon’ is not ‘low-impact’; separate energy emissions from marine and groundwater effects.