City pledges $600 million to fix flooding sewer system
San Francisco has pledged to invest another $600 million into the city’s sewer system in an effort to prevent chronic flooding in low-lying areas as part of an agreement with state water quality officials.
The San Francisco Bay Regional Water Quality Control Board announced the tentative pact, which was negotiated with city officials but needs final approval from the Board of Supervisors and Mayor London Breed. The city’s Public Utilities Commission has recommended approval.
The agreement calls for San Francisco to expand the capacity of its sewer system in three low-lying neighborhoods that frequently overflow in heavy rains. Unlike every other coastal California city, instead of separate sewer systems to handle storm runoff and sewage that needs to be treated, San Francisco has a combined system, which uses the same set of pipes and can be easily overwhelmed by heavy rains, especially in low-lying areas.
When that happens, sewage and stormwater can lift manhole covers and spill onto streets and sidewalks and into houses and garages. The overflows “contain pathogens and other pollutants that pose human health risks and threaten groundwater quality,” according to the water board.
The neighborhoods that would benefit from the sewer capacity expansion include: the Mission near 17th and Folsom streets, Bernal Heights along Alemany Boulevard, and West Portal near 15th Avenue and Wawona Street.
Those neighborhoods and several other lowlying parts of the city have been affected routinely by flooding.
Property owners have successfully sued the city for damage sustained from floods. In a single case with more than 40 plaintiffs from a variety of neighborhoods claiming the city should pay for the damage their property sustained from flooding, officials have authorized just over $1 million in settlements.
In 2015, the federal government began looking
at the city’s sewer system after residents in a handful of low-lying neighborhoods experienced repeated flooding. Correspondence between the SFPUC and the U.S. Environmental Protection Agency at the time, obtained by The Chronicle, shows that the EPA expressed concerns about the SFPUC’s recordkeeping practices.
In addition to the capacity improvements, the agreement calls for San Francisco to develop a plan to more effectively respond to sewage overflows and offer $1.5 million in grants to homeowners each year to install devices that prevent backups of combined sewage and stormwater onto their property. The agreement would require the city to install waterlevel sensors in its sewers to alert it to potential overflows.
“This is a major step forward for San Francisco,” Michael Montgomery, executive officer of the water board, said in a statement. “These substantial investments in its sewer infrastructure will protect residents who have too frequently been exposed to unsafe wastewater for too long and strengthen the resilience of the city’s collection system to extreme weather patterns brought about by climate change.”
Montgomery told The Chronicle the water board had been contemplating a unilateral order mandating that San Francisco make improvements to its sewer system in low-lying neighborhoods, but chose instead to avoid litigation by working on an agreement. The pact was negotiated over the past year, he said.
The overflows have been a long-standing
problem in some lowlying San Francisco neighborhoods, but with sea levels rising and climate change bringing more extreme storms, the need to improve the city’s sewer system was becoming more urgent, Montgomery said.
“This was just a glaring problem as we think about how systems are built for handling more extreme weather,” he said.
San Francisco’s Public Utilities Commission is in the midst of a 20-year, multibillion-dollar project to upgrade its aging system. The $600 million of improvements covered by the agreement, are in addition to that work. Projects covered by the agreement are expected to start within the next two to three years and be completed within seven, Montgomery said.
The three projects included in the agreement were already in the commission’s 10-year plan and have been in planning since 2016, said spokeswoman Cindy Chu.
”While we agree with the Regional Water Board’s goal of reducing overflows from the collection system resulting from heavy rains in the three low-lying neighborhoods, we strongly disagree with their contention that overflows threaten groundwater quality and public health,” she said. “Despite these disagreements, the SFPUC is proposing to enter into this settlement in the interest of working cooperatively with its regulators and arriving at an outcome that is best for the City’s residents.”