Western Sandpipers at Mono Lake
At an October 28 Los Angeles Department of Water & Power (DWP) Board of Commissioners meeting, President Richard Katz lauded progress on the construction of the City’s water recycling plant and declared ”Once the recycled water starts flowing, we won’t need Mono Lake water to meet the supplies in LA.”
Kudos to the Mono Lake Committee for their perseverance. The struggle, to reduce diversions and allow the lake to refill to sustainable levels that support so many migratory bird populations, has been a bit of a roller coater ride ever since the landmark 1994 State Water Board public trust ruling. The prospect of eliminating all diversions is especially appealing – hopefully they will remove all infrastructure and thus eliminate any temptation to resume operations.
The San Francisco Public Utilities Commission is far behind the Los Angeles Department of Water and Power in undoing damage to prized mountain habitats. Indeed, the SFPUC barely acknowledges its legacy in being the only city in the United States to destroy part of a national park.
Recycling water on a large scale is relatively new. San Diego gets credit for leading the way. There are many steps in the process, but the core technology is the same as for desalination – “reverse osmosis” nanofilters. Recycling, however, requires far less energy than desalination because the source water has a much lower salt content. Substantial recycling plants are under construction in San Jose and Orange County, as well as in Los Angeles and San Diego – San Francisco and other Bay Area cities could do the same (see Yosemite’s Opportunity, Restore Hetch Hetchy, 2022).
San Diego’s “Pure Water” recycling plant
Recycling is indeed an option for the SFPUC, and would help reduce noxious effluent being dumped into San Francisco Bay as well. As Yosemite’s Opportunity explains, groundwater banking or enlarging Calaveras Reservoir are also options San Francisco might pursue. System demand, however, has been substantially reduced, and there are a wide range of things San Francisco can do to ensure its customers have reliable supplies when Hetch Hetchy Valley is restored.
It’s inspiring to see the success at Mono Lake. San Francisco surely will not want to be outdone by Los Angeles, will it?