The SFPUC’s Stormwater Management Ordinance Turns 10 Years Old

This May, the SFPUC’s Stormwater Management Ordinance (SMO) celebrated its ten-year anniversary. This is exciting to celebrate, though one might wonder why.

Every year, billions of gallons of rainwater flows into the City’s combined sewer system where stormwater is combined with wastewater from our toilets, bathtub drains, and sinks into one system that collects and treats it all together. That much rainwater hits San Francisco’s streets and gets into the sewer system, so one can imagine that capturing stormwater is critical to the health of the City. Otherwise, pollutants can wash into the bay or ocean or overwhelm the sewer system during heavy rains.

A beautiful green roof at 333 Brannan Street boasts a beautiful green roof that manages stormwater and provides access to beautiful greenspace with seating installations and 360-degree views of the City. A rainwater harvesting system was also implemented to capture stormwater for reuse and offset non-potable water demands.

The Stormwater Management Ordinance was developed in accordance with the Clean Water Act and enacted by then Mayor Gavin Newsom on May 22, 2010. It requires new and redevelopment projects in San Francisco to capture stormwater onsite using green infrastructure. These green infrastructure technologies range from rain gardens to rain barrels or cisterns, permeable paving, and green roofs, just to name a few.

“Since 2010, we have reviewed nearly 500 individual development projects, which is not an easy feat” says Sarah Minick, SFPUC Utility Planning Division Manager. “I’m proud of and thankful for our staff, as these reviews require meticulous attention to detail to ensure that green infrastructure is designed to both meet the SFPUC’s standards and fit the needs of the properties.”

Since its inception, the Stormwater Management Ordinance has made a huge impact on managing stormwater in San Francisco and contributed significantly to the City’s sustainability goals:

  • Over 300 projects have been completed to comply with the Ordinance and are actively managing stormwater on their properties.
  • Collectively these projects manage over 180 million gallons of stormwater annually – enough to fill up over 12,000 swimming pools each year.
  • The total area of these projects is 347 acres, which equals the road area of seven Bay Bridges and seven Golden Gate Bridges added altogether.
Implemented in 2015, the project on 1 Henry Adams St incorporated rain gardens and permeable pavement into a plaza area that is accessible to the public. A green roof was also developed which manages stormwater and provides added habitat without impacting the building footprint.

“Over the years, our team of experts has developed a close working relationship with developers to help enrich the urban experience through the implementation of stormwater management on hundreds of projects. Our review and approval process not only improve the quality of green infrastructure, but also promotes collaborative design and help create meaningful impacts to urban design through water resiliency and urban greening.” said Ken Kortkamp, SFPUC Utility Specialist.

The addition of rain gardens and green roofs to development projects adds a huge benefit by creating beautiful spaces that people and wildlife can enjoy. Over the years, the partnership between the SFPUC Stormwater Management Ordinance team and property owners has resulted in beautifully designed green infrastructure that is both sustainable and enjoyable for its inhabitants.

“What’s great about the ordinance is that it is also contributing to urban greening efforts and habitat creation in San Francisco.” mentions Kelly Teter, SFPUC Watershed Planner.

Looking ahead, the SFPUC has a goal of managing 1 billion gallons of stormwater using green infrastructure by 2050. Minick says, “It’s anticipated that the projects constructed under the ordinance will account for a significant portion of the City’s stormwater management, likely over half of the 1 billion gallons goal.”

This project on 350 Friedell St, under the Stormwater Management Ordinance, used an interior courtyard with rain gardens to meet the stormwater management requirements.