Green Stormwater Infrastructure Features
Stormwater runoff occurs when rain washes over paved surfaces such as sidewalks and streets and carries pollutants directly into storm drains which flow unfiltered to local creeks and the San Francisco Bay.
Green Stormwater Infrastructure helps prevent water pollution by directing runoff into features like rain gardens, pervious paving, and bioretention basins. These features allow stormwater to be naturally filtered by soil, reducing the quantity of runoff and pollutants flowing into storm drains and local creeks. The map below highlights some features that you might see in your neighborhood or might consider in your next landscaping project.
Pervious surfaces let the rain soak into the soil below. Examples of these include driveways made with interlocking pavers or sidewalks made of pervious concrete. These surfaces reduce stormwater runoff pollution that enters into storm drains which flow directly to local waterways.
Rain Barrels and Cisterns
Rain barrels and cisterns are an easy way to collect rainwater from downspouts which can be used later for landscape irrigation. You will conserve water, and reduce runoff over lawns and driveways, which can transport pollutants like pesticides, fertilizers, and automotive fluids to the storm drains.
Rain gardens are landscaped areas that collect and absorb rainwater diverted from residential rooftops and paved surfaces. Rain gardens recharge groundwater and provide a source of food and habitat for wildlife.
Green roofs are building roofs that are covered in soil and vegetation and allow rainwater to soak in. They reduce stormwater runoff, reduce heating and cooling costs, provide recreational opportunities, and attract beneficial wildlife.
Bioretention areas are landscaped areas that capture stormwater runoff and use a special soil mix to remove pollutants. They can be found in parking lots, curb extensions, park strips, traffic circles, and medians. They filter stormwater pollutants and reduce runoff and flooding.
Infiltration trenches are found in parking lots, along street edges, and in alleys. They are excavated trenches backfilled with gravel. They help reduce flooding and pollution from stormwater runoff by capturing and storing runoff which then soaks into the soil below.
Take a tour of local Green Stormwater Features in this video:
- New Stormwater Control Requirements for Large Single-Family Home Development (PDF)
- Rain Barrels and Cisterns Fact Sheet (PDF)
- Rain Garden Fact Sheet (PDF)
- Pervious Pavement Fact Sheet (PDF)
- Hacienda Avenue Fact Sheet (PDF)
- Hacienda Ave/Bay Area Green Infrastructure (PDF)
- Dry Creek Bed Fact Sheet (PDF)
- Landscape Dispersion Fact Sheet (PDF)