ENVIRONMENTAL AND CULTURAL STEWARDSHIP

Where We Want to Be

In the future

  • Existing ecological assets, including wetlands, urban forests, and open space corridors are protected and enhanced. San Francisco Bay and Colma Creek wetlands and marshes provide coastal protection and support regional ecology.

  • Existing City parks and open spaces are managed to support wildlife.

  • South San Francisco has a continuous and equitably distributed tree canopy to improve air quality, provide relief from rising temperatures, and increase connectivity between open spaces and meets the goals established in 2020 Urban Forest Master Plan.

  • Impervious surfaces are reduced to decrease stormwater runoff, mitigate against urban heat islands, and support urban ecology.

  • South San Francisco protects cultural resources for the contributions they make to the city’s history, culture, identity, and quality of life.

Performance

Metrics

01PERFORMANCE METRIC:

Habitat area

Target:

An increase in the acreage of habitat area for local flora and fauna

Data:

as of 2021: 426 acres

02PERFORMANCE METRIC:

Tree canopy

TARGET:

A citywide tree canopy coverage of 22.6% by 2040
All neighborhoods meet the canopy coverage target, prioritizing disadvantaged neighborhoods first

Data:

03PERFORMANCE METRIC:

Environmental stewardship programs

Target:

An increase in environmental stewardship education and interpretation programs and volunteerism

Data:

City to begin tracking data and provide in the future.

04PERFORMANCE METRIC:

Historic resource protection

TARGET:

An increase in the number of historic resources and historic architectural resources eligible for listing in the National Register of Historic Places and California Register of Historic Places

Data:

City to begin tracking data and provide in the future.

How Our Plan

Gets Us There

People standing on hillside overlooking South San Francisco

Ecological and cultural resources provide critical benefits to the residents of South San Francisco. They support healthy ecosystems, improve air and water quality, enhance public health, contribute to the identity and quality of life in the city, and help residents adapt to a changing climate. As South San Francisco grows, the City will foster urban ecology through open space planning and connectivity, habitat diversity, urban forestry, planting and vegetation, and land and vegetation management. The City will steward the San Francisco Bay, Colma Creek, Sign Hill, and San Bruno Mountain and will create an abundant, robust urban forest that supports vegetation and wildlife. The City will protect important cultural resources, including historic architectural, tribal cultural, and archeological resources through identification, preservation, and education initiatives.

The City affirms its commitment to combat climate change by establishing a carbon neutrality goal by 2045. Carbon neutrality is the state of balancing emissions of carbon dioxide with removal or by eliminating emissions from society altogether. The City will accelerate regional and local solutions to reduce GHG emissions through clean and active transportation systems, fossil-fuel free energy systems, green buildings, and zero waste solutions. The City has updated its Climate Action Plan (CAP) to reflect and enhance the General Plan.

Key Issues and Opportunities

Environmental Resources

Environmental Resources

South San Francisco and its surrounding area include many important natural features, such as the San Francisco Bay, San Bruno Mountain, and Colma Creek. These natural features act as landmarks establishing a strong sense of place and location within the community and provide significant opportunities to support urban ecology and biological resources.

Habitat Types

South San Francisco lies at the southern edge of the San Bruno Mountain and adjacent to the San Francisco Bay. Protected areas on San Bruno Mountain preserve expanses of native coastal grasslands, coastal scrub, riparian scrub, and oak woodlands. These habitats support a wide range of flora and fauna, including three federally listed endangered butterflies and a variety of rare plants. To the east of South San Francisco, expanses of tidal marsh, mudflats, ponds, and open water in South San Francisco Bay provide habitat for diverse wetland and aquatic wildlife. The San Francisco Bay also provides essential natural resources for migratory birds on the Pacific Flyway.

While there are habitat areas adjacent to South San Francisco, the city consists almost entirely of developed areas. Pockets of parks and open space provide space for wildlife and humans alike. Colma Creek, San Bruno Creek, and Navigable Slough of San Bruno Creek provide connections between these open areas, and the city’s tree canopy supports wildlife and provides shade. Large infrastructure, like Highway 101, and urban development act as barriers separating the San Francisco Bay from the upper Colma Creek watershed and habitat areas on San Bruno Mountain.

The General Plan provides the opportunity to better connect habitat areas and support biodiversity in the city. By continuing to develop a system of well-connected parks and open spaces; updating guidelines for landscape design and planting; discouraging the use of invasive non-native plantings; and better managing vegetation at parks and open spaces, the City can support biodiversity, improve air and water quality, improve public health, and adapt to a changing climate. There is an opportunity to implement multi-benefit nature-based projects along the San Francisco Bay shoreline and Colma Creek that improve resilience and restore ecosystems. These projects can include marsh and wetlands development, a new beach area, and riparian habitat open space along the San Francisco Bay.

View of San Bruno Mountains

Colma Creek Watershed

A critical feature in South San Francisco, Colma Creek is located between San Bruno Mountain and the San Andreas Fault; it drains an area of 16.6 square miles as a single waterway at the center of the valley. Colma Creek is a perennial stream within the watershed that trends in a southeasterly direction through the center of the city and is the community’s main natural drainage system. The headwaters of Colma Creek originate from San Bruno Mountain located to the north of the city. There are two main tributaries to Colma Creek within the city: Twelve Mile Creek and Spruce Creek.

Since the establishment of the Colma Creek Flood Control Zone in 1964, the urbanization of the Colma Creek watershed saw peak storm water flow steadily increase. The establishment of the Flood Control Zone in response to regular flooding in the sections of the creek downstream from Orange Memorial Park led to Colma Creek being culverted over up until 2006. The San Mateo County Flood and Sea Level Rise Resiliency District (formerly the San Mateo County Flood Control District) contributes to the management of flood risk along Colma Creek.

View on the water of Colma Creek

Flora and Fauna

The city’s natural and urbanized habitats provide areas to support a wide variety of wildlife and plant species. Recent surveys found over 40 sensitive plant species in the city, including eight federally listed species such as the Franciscan manzanita, Presidio manzanita, and robust spineflower. There are six plant species that are State listed species. Recent surveys found 31 sensitive wildlife species recorded throughout the city. This list includes eight federally listed species, including the San Bruno elfin butterfly, mission blue butterfly, and California Ridgway’s rail. Another five species are State listed species. The listed and special-status wildlife and plant species are most likely to be found in the riparian and estuary areas around San Francisco Bay, in the open spaces and hills on San Bruno Mountain and on Sign Hill, and possibly within the city’s existing parks.

Native flowers and grasses along hillside in South San Francisco

Surface Water

Stormwater runoff in the city is collected in storm drains and discharged into Colma Creek or the San Francisco Bay. Some stormwater runoff infiltrates into the ground; however, due to the large amount of impervious surfaces within the city, much of the stormwater flows over land and into existing storm drains. In 2019, the City adopted a Green Infrastructure Plan that establishes guidelines for integrating green infrastructure measures into the city in combination with conventional storm drain system (gray) improvements to manage runoff from storm events.

Section 303(d) of the Clean Water Act requires States to identify waters that do not meet the water quality standards or objectives and thus, are considered “impaired.” Colma Creek and the San Francisco Bay are listed on the Section 303(d) list of the Clean Water Act.

Construction on the Orange Memorial Park Stormwater Capture Project

Ground Water

South San Francisco is located within the boundaries of the Westside and Visitacion Valley Groundwater Basins. The Bayshore Water District of the California Water Service extracts groundwater from the Westside Basin from five wells located within the service area. Groundwater has historically supplied 20% of the Bayshore Water District’s water demand.

Climate change may impact local hydrology and affect natural recharge to the local groundwater aquifers and the quantity of groundwater that could be pumped sustainably over the long-term. Lower rainfall and/or more intense runoff, increased evaporative losses and warmer and shorter winter seasons can alter natural recharge of groundwater. Salinity intrusion into coastal groundwater aquifers due to sea level rise could interfere with local groundwater uses.

Harbors and Fisheries
Cultural Resources
Related Figures
The Bay Trail interpretive sign in front of a body of water

policy

framework

Goal ES-1

Goal ES-1:

The City supports nature in South San Francisco to encourage healthy ecosystems, improve air and water quality, improve public health, and adapt to a changing climate.

Intent:

To foster urban ecology in South San Francisco including open space and connectivity, habitat diversity, urban forestry, planting and vegetation, and land and vegetation management.

Policy ES-1.1: Develop a connected open space network.

Continue to develop a system of well-connected parks and open spaces to support biodiversity, enable the movement of wildlife, and increase climate resilience.

Policy ES-1.2: Strive for habitat diversity across the city.

Strive for habitat diversity ranging from coastal wetlands and marshes to upland habitats.

Policy ES-1.3: Create a connected network of wildlife corridors.

Transform Colma Creek, implement the City’s Urban Forest Master Plan, and manage the Bay Trail and Centennial Way to create a connected network of wildlife corridors.

Policy ES-1.4: Plant for biodiversity.

Discourage the use of invasive non-native plantings in landscape areas across the city, working with regional agencies and local nurseries to educate residents and employers in removing non-native plant species and instead using native species.

  • Action ES-1.4.1: Manage vegetation at parks and open space for biodiversity.

    Manage vegetation at parks and open spaces in South San Francisco to support biodiversity by reducing pesticide use, reducing light pollution, reducing non-native species, and planting native species that provide valuable resources for native wildlife and to increase resilience.

Policy ES-1.5: Conduct equity assessments for conservation efforts.

Assess conservation efforts for distributions of benefits and burdens to diverse and marginalized communities (both geographically bounded and identity-based), including implications for environmental and public health. Engage communities in decision-making about programs and priorities.

For related policies and implementation actions related to urban forestry, landscape design, and recreational programming about ecology and environmental stewardship, see Goals ES-4, ES-5, and PR-9.
Goal ES-2
Goal ES-3
Goal ES-4
Goal ES-5
Goal ES-6
Goal ES-7
Goal ES-8
Goal ES-9
Goal ES-10
Goal ES-11