San Francisco's sewage and stormwater - making the system sustainable

Sewage is the hidden but vital underbelly of San Francisco's efforts to become a green city. The city's $3.5 billion Sewage System Master Plan, now being written, will be a key success or failure in the city's efforts to control its environmental impacts. The Sierra Club is working with the San Francisco Sustainable Watersheds Alliance (SWAle) to track and shape the plan.

The master-planning process began in 2002 after SWAle members and other concerned San Franciscans persuaded the city's Public Utilities Commission (PUC) that it would need real community involvement to win public support for the extensive investment needed to rebuild San Francisco's wastewater infrastructure. The current draft plan is still far from perfect, but the city is at least poised to bring its infrastructure into the 21st century.

Unlike other Bay Area cities, San Francisco uses a combined wastewater system: 900 miles of pipe carry both sewage and stormwater. Large portions of the system are over 75 years old and approaching danger levels for failure. Because of a voter-mandated rate freeze, lifted in 2002, the PUC is playing catch-up from years of deferred maintenance.

The city's Westside sewage-treatment plant, a state-of-the-art enclosed facility near the Zoo but barely visible to the public, was completed in the early '90s, but it treats only about 20% of the city's sewage. The Southeast Plant, which treats the remaining 80%, is a relic of the '50s, long past its useful life. Across the street from homes and on the edge of a residential neighborhood, the plant has been the source of long-standing environmental-justice complaints about odors, blighting effects, and the stigma of being "the city's outhouse". During heavy or intense rainstorms, water overwhelms the system, causing billions of gallons per year of sewage and contaminated stormwater to overflow into San Francisco Bay and the Pacific Ocean, with impacts on wildlife, recreational users, and low-income families who rely on the Bay for sustenance.

To address these serious infrastructure challenges, PUC staff developing the Sewage System Master Plan are advocating several actions:

• reduction of combined sewer discharges (formerly called combined sewage overflows, CSOs) into San Francisco Bay and the Pacific Ocean by 40% - through plumbing changes and also through investment in "green infrastructure" projects such as swales, permeable pavement, and removal of pavement;
• a stormwater treatment and retention program based on watersheds - trying to retain and reuse the rain in the watershed where it falls;
• doubling the pace of the PUC's pipe repair and replacement program;
• minimizing the agency's carbon footprint through alternative-energy measures such as food digestion and improvements in methane recovery.

Such an ambitious program is long overdue.

Despite these admirable proposals, the plan does have shortcomings.

• The PUC recognizes the need to rebuild the Southeast Treatment Plant but continues to favor the current site. The process needs to give due consideration to possible preferable alternatives.
• Questions remain about the scale and effectiveness of the green-infrastructure program.
• The plan needs a program to restore San Francisco's hydrology through measures such as daylighting streams, restoration of wetlands, and creation of habitat.
• The plan should make a stronger commitment to water recycling, including provision of recycled water to new developments and industry on the east side of the city. Recycled water can be a key source of new water supplies that will allow us to reduce both diversions from the Tuolumne River (see January-February Yodeler, page 14) and the discharge of treated wastewater into the Bay and Ocean.
• The plan should give greater consideration to decentralized treatment - the use of multiple small treatment plants rather than one large central plant. This can improve system reliability, conserve energy (since there would be less pumping of water), alleviate the disproportionate impacts of having a large plant at one location, and increase water recycling.

Through these measures San Francisco can not only work to reverse years of environmental damage but also rise to the cutting edge of urban wastewater management.

Staff is still working on the draft plan. The PUC commissioners, who will have the final say, have yet to receive public comment and weigh in.

WhatYouCanDo

A draft of the "Recommended Program" will be released sometime in the spring but we do not yet know when the public will have the opportunity to speak up to the commission. To learn more and to be added to SWAle's Action Alert list, contact SWAle co-chair Alex Lantsberg at: alex -at- sfswale.org or (415) 794-2539. The PUC web site provides extensive background information about the Master Plan, staff's public presentations, and a way to get on the mailing list to be notified of upcoming hearings.

Alex Lantsberg and Jennifer Clary, co-chairs, SWAle