Objective ES.2 Restore, preserve and protect healthy natural habitats

Indicators, Development Targets and Policies/Design Strategies

Indicators Development Targets Policies/Design Strategies
Primary
a. Miles of accessible shoreline

Benchmark: Is the project located at a distance greater than 100 feet from existing shorelines of water bodies--seas, lakes, rivers, streams and tributaries--and wetlands?

Regulatory minimum: The SF Bay Conservation and Development Commission (BCDC) regulates development within the 100-foot shoreline band.  Permitted uses include open space; public recreation and access; waterfront commercial recreation uses; limited residential; and off-street parking related to these uses.  The BCDC requires the maximum feasible public access as a condition of permit approval for new development within the 100-foot shoreline band.  SF Planning Code Section SEC. 330.4.requires construction of any residential or commercial building, structure, or project as defined in Section 330.2 subject to coastal zone permit review.
  • Require green roofs on new municipal and on existing municipal buildings when their roofs are replaced.1
  • Provide financial incentives that offset initial and ongoing operation costs of greenroofs (e.g., subsidies or grants for capital costs, reduction or rebate in water or energy rates).2,3
  • Design the project site to maintain natural stormwater flows by promoting infiltration trenches.4
  • Require the use of porous surface materials like vegetated roofs, porous pavement, and other measures to minimize impervious surfaces and increase natural ground absorption of rainfall.5
  • Reuse stormwater for non-potable uses such as landscape irrigation, toilet and urinal flushing and custodial uses.6-8
  • Improve the safety, continuity, and functionality of transit, bicycle, disabled, and pedestrian access to and between parks, the shoreline, open spaces, and recreation facilities, especially from new developments through the use of established best practices. 9
  • Prevent any net loss of open space by prohibiting public facilities such as parking garages, streets, and buildings on existing open space. If any potential loss is anticipated, development shall replace the open space with a 1:1 ratio within the project area or community.10
  • When developing a new project, ensure that each unit has access to water sources to install and maintain green space.11

  • Assess state/municipal surplus property that could be retained for open space, community garderns and/or be developed into future park sites.12
b. Acres of significant natural areas

Benchmark: If the project develops or alters land deemed to be significant natural resource areas, does the project preserve or restore 20% of the development parcel area to a natural condition with regard to flora?

Regulatory minimum: The SF General Plan Open Space Element Policy 2.13 provides information on preserving and protecting significant natural resource areas and defines criteria to be used to determine what constitutes a significant natural resource area worthy of protection.
c. Acres of public open space per 1,000 population

Benchmark: Does the project meet or achieve a standard of 10 acres of publicly accessible open space per 1,000 population in the planning area?  

Regulatory minimum:  The SF General Plan Open Space Element Policy 2.2 prohibits proposals for nonrecreational uses in public parks and playgrounds and gives priority to open space land use designation when public land becomes surplus.

d. Number of trees

Benchmark: Does the project provide a continuous row of appropriately spaced trees at all streets adjacent to the project?

Regulatory minimum: SF Planning Code Section 143 requires street [trees] to be installed by the owner or developer in the case of construction of a new building, relocation of a building, or addition of gross floor area equal to 20% or change of 20% or more of the occupied floor area of an existing building to another use. The street trees installed shall be a minimum of one 24-inch box tree for each 20 feet of frontage of the property along each street or alley, with any remaining fraction of 10 feet or more of frontage requiring an additional tree.

Secondary
e. Proportion of impervious ground surfaces

Benchmark: Does the project use porous pavement materials on drives, sidewalks, parking lots and plazas? AND apply the "SFPUC Stormwater Design Guidelines"?

Regulatory minimum: See the SFPUC Stormwater Design Guidelines (http://sfwater.org/File/FactSheets /DRAFTStormwaterDesignGuidelines.pdf). The Board of Supervisors passed the Permeable Sidewalk Landscaping Permit in 2006. The ordinance created a method by which individual property owners can increase the green space around their homes by allowing garden installations in sidewalk areas.
f. Proportion of buildings with green roofs

Benchmark: Does the project establish and maintain green roofing or rooftop gardens on at least 25% of usable roof space?

Health-based Rationale

  • The leafy canopy of trees reduces surrounding temperatures, provides natural shade, and reduces ultraviolet radiation (UV) and the risk of skin cancer.13
  • Trees reduce the amount of storm water runoff, thereby improving water quality and management and reducing energy consumption; Trees also increase oxygen production and reduce levels of smog, thereby improving air quality.14
  • Trees and greens space improve the physical environment by removing air pollution from air and mitigating the urban heat island effect produced by concrete and glass.15
  • Presence of green surroundings in urban settings is associated with fewer crime reports after controlling for the number of apartments per building, building height, vacancy rate, and number of occupied units per building.16
  • Green roofs reduce stormwater runoff volumes and lower temperatures in urban environments; reduce energy insulation.17
  • More generally, living in proximity to green space is associated with reduced self-reported health symptoms, better self-rated health, and higher scores on general health questionnaires.18
  • Parks and open spaces provide needed reprieve from everyday stressors, acting as “escape facilities”. Being able to escape fast-paced urban environments improves the health by reducing stress and depression and improving the ability to focus, pay attention, be productive, and recover from illness.19
  • A study in Chicago showed that people living in a housing project who had some green space near them scored higher on the ability to manage major life issues, they procrastinated less, found their issues to be less difficult, and reported them to be less severe and long-standing than those who lived in barren surroundings.20
  • In a study in Chicago, observations of vegetated areas with trees and grass indicated that green spaces contained on average 90% more people. In addition, 83% more people were involved in social activities in green spaces vs. barren spaces.21

Established Standards

  1. The San Francisco General Plan's Recreation and Open Space Element cites the National Parks and Recreation Association (NPRA)'s nationally recognized standard of 10 acres of open space per 1,000 population in cities. See Policy 2.1: http://www.sfgov.org/site/planning_index.asp?id=41414
  2. The SF General Plan Open Space Element requires a 1:1 replacement of open space lost in the course of development. Available at: http://www.municode.com/Resources/gateway.asp?sid=5&browseAllCodes=San%20Francisco
  3. SF Planning Code Section 143 requires that a project sponsor provide an in-lieu payment to the Department of Public Works/Bureau of Urban Forests for a tree to be planted and maintained within the neighborhood should it not be possible to plant a tree every 20 feet. Available at: http://www.municode.com/Resources/gateway.asp?sid=5&browseAllCodes=San%20Francisco
  4. The SF Bay Conservation and Development Commission (BCDC) regulates development within the 100-foot shoreline band. Permitted uses include open space; public recreation and access; waterfront commercial recreation uses; limited residential; and off-street parking related to these uses. The BCDC requires the maximum feasible public access as a condition of permit approval for new development within the 100-foot shoreline band.
  5. SF Planning Code Section 143 requires that a project sponsor provide an in-lieu payment to the Department of Public Works/Bureau of Urban Forests for a tree to be planted and maintained within the neighborhood should it not be possible to plant a tree every 20 feet.
1. Toronto, Canada Green Roofs Policy http://www.toronto.ca/greenroofs/policy.htm#making
2. UC Davis. "Green Roofs: A Sustainable Technology Sustainability and the Built Environment UC Davis Extension" http://extension.ucdavis.edu/unit/green_building_and_sustainability/pdf/resources/green_roof.pdf
3. City of Chicago, Green Roofs Policies and Incentives. http://egov.cityofchicago.org/city/webportal/portalContentItemAction.do?topChannelName=HomePage&contentOID=536910903&Failed_Reason=Invalid+timestamp,+engine+has+been+restarted&contenTypeName=COC_EDITORIAL&com.broadvision.session.new=Yes&Failed_Page=%2fwebportal%2fportalContentItemAction.do
4. Stormwater Manager's Resource Center: Stormwater Management Fact Sheet: Infiltration Trench. http://www.stormwatercenter.net/Assorted%20Fact%20Sheets/Tool6_Stormwater_Practices/Infiltration%20Practice/Infiltration%20Trench.htm
5. University of Connecticut. Nonpoint Education for Municipal Officials, Planning for Stormwater: Permeable Pavements http://nemo.uconn.edu/tools/stormwater/pavements.htm
6. US EPA Region 9: Guidelines for Water Reuse. http://www.epa.gov/ord/NRMRL/pubs/625r04108/625r04108.pdf
7. City of San Diego Water Department: Recycled Water: http://www.sandiego.gov/water/recycled/
8. Tuscan Water: Reclaimed Water. http://www.ci.tucson.az.us/water/reclaimed_water.htm
9. Victoria Transport Policy Institute: Pedestrian and Bicycle Planning A Guide to Best Practices. http://www.vtpi.org/nmtguide.doc
10. San Francisco Planning Department: Recreation and Open Space. http://www.sfgov.org/site/planning_index.asp?id=24887#ros.cty.2.2
11. City of Chicago, Green Roofs Policies and Incentives. http://egov.cityofchicago.org/city/webportal/portalContentItemAction.do?topChannelName=HomePage&contentOID=536910903&Failed_Reason=Invalid+timestamp,+engine+has+been+restarted&contenTypeName=COC_EDITORIAL&com.broadvision.session.new=Yes&Failed_Page=%2fwebportal%2fportalContentItemAction.do
12. San Francisco Planning Department: Recreation and Open Space. http://openspace.sfplanning.org/
13. Grant R, Heisler G, Gao W. Estimation of Pedestrian Level UV exposure under trees. Photochemistry and Photobiology. 2002;75(4):369-376.
14. SF Urban Forest Council. 2008 Annual Report. Accessed at: http://www.sfenvironment.org/our_policies/overview.html?ssi=16#Reports
15. Parks for People: Why America Needs more City Parks and Open Space. San Francisco: The Trust for Public Land, 2003.
16. Kuo FE, Sullivan WC. Environment and crime in the inner city: does vegetation reduce crime? Environment and Behavior. 2001;33(3):343-367.
17. DeNardo J, Jarrett AR, Manbeck HB, Beattie DJ, Berghage RD. Green roof mitigation of stormwater and energy usage. Paper number: 032305, 2003 ASAE Annual Meeting.
18. Vries S, de Verheij RA, Groenewegen PP, Spreeuwenberg P. Natural environments - healthy environments? An exploratory analysis of the relationship between green space and health. Environment and Planning A. 2003;35:1717-1731.
19. Maller C, Townsend M, Pryor A, Brown P, St. Leger L. 2005. Healthy nature healthy people: ‘contact with nature’ as an upstream health promotion intervention for populations. Health Promotion International 21(1):45-53.
20. Guite HF, Clark C, Ackrill G. 2006. The impact of physical and urban environment on mental well-being. Public Health 120:1117-1126.
21. Sullivan WC, Kuo FE, DePooter Sf. 2004. The fruit of urban nature: Vital neighborhood spaces. Environment and Behavior 36(5):678-700.