San Francisco Is Saving Water But Still Seeking Drought Solutions

The biggest rainy season in years has ended this month in a partial recovery from a long drought.

But while water districts in other parts of the state have just convinced Governor Jerry Brown to ease some restrictions on water usage this summer, San Francisco is staying focused on the long-term problems.

“We aren’t out of the drought," Michael Carlin of the city's Public Utilities Commission told an audience at a Commonwealth Club presentation that Hoodline attended in late April. "One good year doesn’t mean we are done.”

In his update on El Niño, the California snowpack, and the state’s current water levels, the PUC's deputy general manager and chief operating officer told the crowd that there had been some improvement — at least locally.

The SFPUC pegs average residential water use at 44 gallons per day, less than half of the California average of 94 gallons per day and among the lowest in the state, he said. In 2015, San Francisco saw its lowest annual system demand for water since 1977 despite a much larger population.

And in the first four months of 2016, the Hetch Hetchy Reservoir — the city's main water source, 165 miles east in the Sierra Nevada mountains —  has been above its median level due to all the winter rain.

Today, San Francisco is well within the 25% citywide water use reduction mandated by Governor Jerry Brown’s January 2014 State of Emergency declaration on California’s multi-year drought (the one he just scaled back).

“We had a very good year," Carlin acknowledged. "We are doing better than we expected.”  

Upstream Problems

With 37 million gallons per day used by San Francisco’s 845,602 residents (in the 2014-15 fiscal year), the city still relies on Hetch Hetchy for 85 percent of its water supply.

This means that what happens in the Sierra Nevadas around Yosemite National Park directly impacts the quality and quantity of San Francisco’s water. And there have recently been serious issues — that aren't going away anytime soon.

Rim Fire in 2013. | Photo via the California National Guard/Flickr

In the August of 2013, the Rim Fire burned some 260,000 acres around the Hetch Hetchy Reservoir, damaging power houses and water distribution lines and distributing ash throughout the watershed. It was one of the largest fires in the state's history, and the causes were mostly long-term: flawed fire suppression practices, drought and tree disease.

As in much of the western US, forest managers in California have for many decades prevented small naturally-occurring wildfires from clearing out new and weaker trees. Instead, forests have become crowded, and instead of a natural thinning, wildfires today are more likely to burn down an entire forest.

Drought has also put new pressure on ecological relationships between pests and trees, notably bark beetles and pine and fir trees in the Sierra Nevadas .

In years of normal rainfall, the trees are able to defend themselves against the beetle's attack by pushing them out with the sap they produce naturally. In a sustained drought, though, the trees don’t have enough moisture to produce the sap needed to combat the beetles. With the upper hand, the beetle’s attack kills the tree. The more dead trees, the more fodder for forest fires. The more fire, the greater the threat to the water quality, the dams and other hydroelectric equipment that keep San Francisco sated.

It is the lack of political will to fix problems affecting forests like those in the Sierras, according to Patrick Koepele, Executive Director of the Tuolumne River Trust, that will have the most drastic impact on San Francisco’s drinking water in the long term.

A map of the Hetch Hetchy system. | By:  Shannon1/Wikimedia 

The ongoing vulnerability of Hetch Hetchy and the greater Tuolumne watershed has led San Francisco to continue looking elsewhere, despite its enviably large reservoir.  

What's Next

The city is trying to introduce more ways of pumping, cleaning and reusing water locally.

The SFPUC has a policy goal of acquiring 10 million gallons per day from local resources by 2018.  

There are seven groundwater basins in San Francisco proper, including Westside in the Sunset District, Islais Valley in Glen Park, Lobos in the Richmond, Marina, Downtown, South San Francisco and Visitacion Valley.

San Francisco residents do not currently get any drinking water from the city’s groundwater but the 45 square mile Westside Basin, comprised of a series of aquifers stretching from Golden Gate Park to San Bruno, has been identified as a future source that will provide 4 million gallons per day, approximately 5% of the city’s drinking water supply.

San Francisco’s non-potable water program, on the other hand, has the ability to offset millions of gallons of water through the reuse of greywater (wastewater primarily from sinks, showers and washing machines) for things like toilet flushing and landscaping.

The Harding Park Recycled Water Project, the Recycled Water Truck-Fill Station, and other projects save several thousands of gallons of San Francisco drinking water each day by recycling non-potable water for use on parks, and to irrigate road landscaping, clean streets and flush sewers.

Peter Drekmeier, policy director for the Tuolumne River Trust, told the Commonwealth club audience that San Francisco is a national leader in managing its watershed. But he noted that there's still a “yuck factor” among the public in water reuse (particularly in the treatment and reuse of graywater as drinking water, which is not among San Francisco’s current goals) and that the legislation has yet to fully catch up to what's possible.

Harding Park. | Photo: Anayst/Wikimedia

Slowly, however, things are changing.

The SFPUC is currently working with the National Water Research Institute on recommendations for public health standards for treated alternate water sources for non-potable use. In July 2015 San Francisco legislated that all new buildings over 250,000 square feet must install an onsite non-potable water reuse system. The SFPUC’s non-potable water program also offers grants of $250,000 to individual buildings and $500,000 to districts for the construction of water reuse systems.

San Francisco is also part of a multi-city investigation into the development of a regional water supply using the desalination of brackish water to serve 5.6 million residents and businesses in the Bay Area. Smaller scale city-wide programs, such as the Rainwater Harvesting Program launched in October 2015 provides free rain barrels to one and two unit San Francisco homes. In 2016, the program has expanded to include cisterns.

Despite a good El Niño year, drought, climate change and overpopulation remain very real long-term problems for the security of San Francisco’s water supply.

And according to the US Drought Monitor, California is still in “extreme drought” (one step down from last year when the state’s status was “exceptional drought). San Francisco has done well so far but as Carlin told the crowd, “people need to keep conserving."  And the city needs to keep looking for more options. 

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San francisco is saving water but still seeking drought solutions