San Francisco study proves impaired source still feasible

The Marin Municipal Water District (MMWD), near San Francisco, USA, has been exploring seawater desalination to provide a drought-proof supplement to its over-extended water supply. Desalination of San Francisco Bay water presents challenges for pretreatment due to the frequent changes in water quality from the ebb and flow of the tides and winds, seasonal changes in the flows of two major rivers (Sacramento and San Joaquin), and impacts from stormwater and industrial discharges. It also presents technical and sociological challenges to convince customers that high quality drinking water can be produced from an impaired water source. A 12-month desalination pilot program was carried out to achieve the following main objectives: Test different pretreatment processes and membrane performance to determine which ones perform best to process SF Bay source water. Perform studies to address environmental concerns to facilitate permit applications and support an environmental impact report. Demonstrate that SWRO can reliably produce high-quality drinking water through comprehensive water-quality testing, tours and public outreach This article appeared in D&WR magazine’s August/September 2008 issue.

The Marin Municipal Water District (MMWD), near San Francisco, USA, has been exploring seawater desalination to provide a drought-proof supplement to its over-extended water supply.

Desalination of San Francisco Bay water presents challenges for pretreatment due to the frequent changes in water quality from the ebb and flow of the tides and winds, seasonal changes in the flows of two major rivers (Sacramento and San Joaquin), and impacts from stormwater and industrial discharges. It also presents technical and sociological challenges to convince customers that high quality drinking water can be produced from an impaired water source.

A 12-month desalination pilot program was carried out to achieve the following main objectives:

  • Test different pretreatment processes and membrane performance to determine which ones perform best to process SF Bay source water.
  • Perform studies to address environmental concerns to facilitate permit applications and support an environmental impact report.
  • Demonstrate that SWRO can reliably produce high-quality drinking water through comprehensive water-quality testing, tours and public outreach
  • This article appeared in D&WR magazine’s August/September 2008 issue.