Descriptive Title: Ratio of bicycle path and lane miles to road miles

Geographic Unit of Analysis:

Street segments

Ratio of miles of bike lanes and paths to road miles (2014)
NeighborhoodMiles of bike lanes and pathsRoad milesRatio of bike lanes and paths to road miles
Bayview/Hunter's Point 11 97.6 0.11
Bernal Heights 5 39.8 0.13
Castro/Upper Market 2.6 27 0.1
Chinatown 0.1 9.6 0.01
Excelsior 1.7 39.9 0.04
Financial District/South Beach 10.8 36 0.3
Glen Park 3.2 18.1 0.18
Golden Gate Park 19.7 24.3 0.81
Haight Ashbury 0.3 14.9 0.02
Hayes Valley 2.1 16.4 0.13
Inner Richmond 3.3 19.1 0.17
Inner Sunset 3.1 37.4 0.08
Japantown 1.2 4 0.29
Lakeshore 18.3 29.4 0.62
Lincoln Park 1.4 2.9 0.49
Lone Mountain/USF 3.5 15.7 0.23
Marina 4.4 29.1 0.15
McLaren Park 0.5 5.8 0.08
Mission 16.9 61.1 0.28
Mission Bay 8.1 19.8 0.41
Nob Hill 0 14.1 0
Noe Valley 2 28.9 0.07
North Beach 3.3 14.3 0.23
Oceanview/Merced/Ingleside 2.3 33 0.07
Outer Mission 7 38.7 0.18
Outer Richmond 7.8 45.1 0.17
Pacific Heights 0 21.6 0
Portola 2.6 29.3 0.09
Potrero Hill 4.7 33.8 0.14
Presidio 24.3 42.5 0.57
Presidio Heights 1.3 13.4 0.09
Russian Hill 2.3 16.5 0.14
San Francisco 215.8 1204.3 0.18
Seacliff 1.9 5.2 0.37
South of Market 8.8 29.9 0.29
Sunset/Parkside 14.7 110.8 0.13
Tenderloin 1.7 13.2 0.13
Treasure Island 3 20 0.15
Twin Peaks 0 15.3 0
Visitacion Valley 0.9 17.6 0.05
West of Twin Peaks 8.2 94.5 0.09
Western Addition 2 18.4 0.11

Why Is This An Indicator Of Health and Sustainability?

Cities with well-maintained, highly connected, and safe bicycle infrastructure can help encourage people to choose bicycling as their main mode of transportation.  A growing body of research indicates that on-road marked bike lanes have a positive effect on cyclist safety.a  Promotion of cycling in San Francisco can improve public health if projects and policies aim to provide safe and convenient bicycle access to all services, commercial and residential areas, regional and local transportation systems  - along with safe and convenient bicycle parking facilities and connections to transit (e.g., bike racks on buses).b  Built environment factors that are associated with biking as an alternative to driving include increased resident and employment density, greater diversity of land use mix (e.g. residential land use near retail land uses), shorter distances to destinations, and street design (e.g. presence of protected bike lanes and paths, grid street networks).c 

Cycling instead of using motor-vehicle transport can improve public health because bicycling is a clean, economical, and healthy transportation mode.  Cycling as a driving alternative reduces traffic-related noise, air pollution and congestion,d provides an equitable form of transportation to people in all localities and income brackets, and improves personal health through increased physical activity.  Encouraging and facilitating active transportation – walking or cycling - as a form of travel for utilitarian trips is a key strategy for increasing daily physical activity.e  Personal health benefits of increased physical activity in children and youth include enhanced cardiorespiratory and muscular fitness, bone health, body mass and composition.  In adults and older adults, strong evidence demonstrates that, compared to less active counterparts, more active men and women have lower rates of all-cause mortality, coronary heart disease, high blood pressure, stroke, type 2 diabetes, metabolic syndrome, colon cancer, breast cancer, and depression.  For older adults, strong evidence indicates that being physically active is associated with higher levels of functional health, a lower risk of falling, and better cognitive function.f  A 2011 report issued by an international group of experts of data from Copenhagen documents all-cause mortality benefits from regular cycling for commuting controlling for socio-demographic and leisure time physical activity.g

Interpretation and Geographic Equity Analysis

Bicycle Network Terminology: San Francisco’s 70 miles of bicycle paths, or Class I bikeways, provide a separate right of way for the exclusive use by bicyclists and pedestrians with minimized cross flow by motorists.  There are 146 miles of bicycle lanes, or Class II bikeways, that are striped lanes for one-way bicycle travel in the same direction as motor vehicle traffic on a street or highway, delineated specifically for use by bicyclists.  Additionally, there are 219 miles of bicycle routes, or Class III bikeways that are designated by bicycle route signage along roadways and provide shared use with pedestrian or motor vehicle traffic. Routes may consist of a variety of treatments including streets with wide curb lanes, sharrows, traffic calming measures, or simply streets signed as bicycle routes.h

The bicycle network ratio table illustrates the proportion of bicycle path and lane miles to overall road miles within each analysis neighborhood in San Francisco.  In 2014 there were 215.8 miles of  bicycle paths and lanes, compared to 1,204 miles of road.  Citywide, San Francisco has 5.6 miles of vehicle road miles to every 1 mile of protected bike paths and lanes (5.6:1). However, bicycle paths and lanes are unevenly distributed and even absent from some neighborhoods as seen the Bicycle Network Map.

Neighborhood ratios range from 21.6:0 in Pacific Heights to 1.6:1 in Lakeshore. The 5 neighborhoods with the largest gaps in bike lanes and paths relative to vehicle road miles are Nob Hill, Pacific Heights, Twin Peaks, Chinatown, and Haight Ashbury. The hilly topography in some of these neighborhoods may lie behind their lack of bike paths and lanes. The neighborhoods with the most bike lanes and paths per street mile include: Golden Gate Park, Lakeshore, Presidio, Lincoln Park, and Mission Bay. Many of these neighborhoods are parks and likely have many miles of bike lanes and paths for recreational purposes.

Methods

2014 bicycle path, lane and route network road locations were gathered from the San Francisco Municipal Transportation Agency (SFMTA). 

The entire bike network is displayed in the map by facility type, but only paths and lanes are used to calculate the ratio of bicycle infrastructure to vehicle infrastructure table.  Only bike paths and lanes were used for the analysis because these facilities offer separate or specifically delineated physical  rights of way for use by bicyclists, distinguished from space for motor vehicles.

Limitations

Road miles reported include public (including unaccepted), park, and military streets, freeways and freeway ramps, and exclude private streets.  The miles of bicycle lanes and paths (as well as roadway miles) are the approximate length of the network and not the actual number of miles of bicycle facilities (i.e., a two-way street with bicycle lanes in each direction and a one-way street with a bicycle lane in one direction are counted the same).

Many of the bicycle network paths, lanes, and routes fall on the boundaries of analysis neighborhoods.  Neighborhoods are generally separated by arterial roads, some of which include bicycle infrastructure.  Because of this border issue, some of the neighborhood vehicle-to-bicycle infrastructure ratio estimations include roadways that are included in the ratio calculation for multiple neighborhoods.

Other factors important to supporting cycling as an alternative to driving not represented with this indicator include the provision of secure bike parking and facilities (e.g., bike racks on buses or parking at transit hubs) that support bike-to-transit connections. 

Please review the 2014 SFMTA Bicycle Count Report for more information on what San Francisco has accomplished in regards to bicycle infrastructure improvements, as well as strategies being developed to increase biking activity. https://www.sfmta.com/sites/default/files/reports/2015/SFMTA%202015%20Annual%20Bicycle%20Count%20Survey.pdf

Data Source

The San Francisco Municipal Transportation Agency (SFMTA) Bicycle Network of 2014.

The San Francisco Department of Public Works (SFDPW) Street Network provided the overall road miles throughout San Francisco for use to calculate the ratio of bicycle path and lane infrastructure miles to vehicle road miles citywide and by planning neighborhood.

Table data is presented by analysis neighborhood.

Detailed information regarding census data, geographic units of analysis, their definitions, and their boundaries can be found at the following links:

Interactive boundaries map

http://sfindicatorproject.org/resources/data_map_methods

  1. Reynolds CCO, et al. 2009. The impact of transportation infrastructure on bicycling injuries and crashes: a review of the literature. Environmental Health 8:47.

  2. San Francisco Municipal Transportation Agency.  San Francisco Bicycle Plan: Policy Framework. San Francisco, Ca: San Francisco Municipal Transportation Agency, June 26, 2009. http://www.sfmta.com/cms/bproj/documents/San_Francisco_Bicycle_Plan_June_26_2009_002.pdf

  3. Frank LD, Schmid TL, Sallis JF, Chapman J, Saelens BE. 2005. Linking objectively measured physical activity with objectively measured urban form. American Journal of Preventive Medicine 28(282): 117-125.

  4. PolicyLink, Prevention Institute, the Convergence Partnership. Healthy, Equitable Transportation Policy.  2009. Ed. Shireen Malekafzali. Available at: http://www.convergencepartnership.org/atf/cf/%7B245a9b44-6ded-4abd-a392-ae583809e350%7D/HEALTHTRANS_FULLBOOK_FINAL.PDF.

  5. Transportation Research Board, Institute of Medicine of the National Academies: Committee on Physical Activity, Health, Transportation, and Land Use. 2005. Does the built environment influence physical activity?: examining the evidence. Special report 282. Washington, DC: Transportation Research Board. 

  6. Physical Activity Guidelines Advisory Committee. 2008. Physical Activity Guidelines Advisory Committee Report, 2008. Washington, DC: U.S. Department of Health and Human Services.

  7. WHO/Europe HEAT (Health Economic Assessment Tool). 2011. World Health Organization, Regional Office for Europe.  Available at:  http://www.heatwalkingcycling.org/index.php.  

  8. San Francisco Municipal Transportation Agency.  San Francisco Bicycle Plan: Policy Framework. San Francisco, Ca: San Francisco Municipal Transportation Agency, June 26, 2009. http://www.sfmta.com/cms/bproj/documents/San_Francisco_Bicycle_Plan_June_26_2009_002.pdf