 |
|
Stormwater Design Guidelines for New Development and Redevelopment Projects in San Francisco
February 2007 Stormwater Design Guidelines Staff Report (PDF)
March 8, 2007 Stormwater Design Guidelines Workshop Flyer (PDF)
Minutes for March 8 Stormwater Design Guidelines Workshop (PDF)
What are Stormwater Design Guidelines?
The Port of San Francisco (Port) and the San Francisco Public Utilities Commission (SFPUC) are developing the San Francisco Stormwater Design Guidelines (“Design Guidelines”). The Design Guidelines will improve San Francisco’s environment by reducing pollution in stormwater runoff in areas of new development and redevelopment. The Design Guidelines will be applied in areas of San Francisco served by separate storm sewers that discharge directly to local lakes or San Francisco Bay. Given current trends in development, at this time mostly Bay waterfront parcels will be affected.
What is stormwater runoff and why is it a concern?
Stormwater runoff is rainwater that flows over the land surface and through collection pipes. In vegetated areas such as forests, fields and wetlands, rainwater seeps slowly into the ground, limiting runoff. However, when rain falls on paved concrete and other hard (impervious) surfaces such as those found in most of San Francisco, it runs off quickly and is conveyed by pipes and other drainage features. Though starting as relatively pure rainwater, stormwater runoff collects pollutants as it flows over impervious surfaces. For example, runoff from parking lots picks up oil and grease from leaking engines, copper from worn brake linings, and zinc from tires. Although most runoff in San Francisco flows into the combined sewer system and receives treatment at the city’s two sewage treatment plants, there are a few areas in the city that discharge directly into San Francisco Bay or other surface water such as Lake Merced without receiving any treatment. These polluted stormwater flows can be detrimental to aquatic and other life. The Design Guidelines will help improve San Francisco’s environment by reducing pollution in water that runs to the bay or other waters from newly constructed facilities.
How can San Francisco help reduce the detrimental impacts of stormwater runoff?
One way to help reduce the detrimental impacts of stormwater runoff is by changing the way we approach new construction. New development and redevelopment projects can be designed to minimize pollutant exposure within the project area. Through careful pre-construction planning and designing, new development and redevelopment projects can be built to:
- Minimize impervious surfaces, which would allow more rainfall to soak into the ground
- Reduce the volume and intensity of storm water runoff, which would reduce flows that end up in the receiving waters
- Convey and treat storm water runoff using landscape features and other “green” systems to provide treatment to the pollutants in the runoff
Studies performed around the world show that proactive site planning and design is the most cost-effective approach for reducing stormwater pollution.
What is San Francisco doing to address stormwater impacts associated with new development and redevelopment projects?
As the owners and operators of San Francisco’s storm drain systems, the Port and the SFPUC have teamed to develop the San Francisco Stormwater Design Guidelines. The Design Guidelines will apply to new development and redevelopment in areas of San Francisco served by separate storm sewers (e.g., storm sewers that discharge directly to receiving waters). The Port and the SFPUC invite you to participate in the development of the Design Guidelines.
Is San Francisco required to develop Stormwater Design Guidelines?
Yes - a Clean Water Act discharge permit administered by the State Water Resources Control Board (SWRCB) requires local agencies to develop programs for the control of stormwater runoff for the life of a project (“post-construction control” of stormwater). The Design Guidelines will comply with the mandate of this permit, while at the same time providing a vehicle through which planners, designers, engineers and developers can work together toward a more sustainable city.
How can I help improve San Francisco’s environment?
Be a part of the solution and help us improve San Francisco’s environment through innovative stormwater management. Please attend our first public meeting on March 8, 2007 from 6 PM to 9 PM at the Port’s offices at Pier 1 in San Francisco.
Interested in learning more about stormwater post-construction controls and low-impact design?
USEPA Post-Construction Controls Webpage
SFPUC Low Impact Design Webpage
USEPA Low Impact Design Webpage
For More Information Call or Contact:
John Mundy Rosey Jencks
john.mundy@sfport.com (415) 934-5762
(415) 274-0256
|
|
|