By directing growth to already developed areas, local jurisdictions can reinvest in existing neighborhoods, increase access to transportation systems, and preserve the character of adjacent rural communities. Focusing new commercial and residential developments near rail stations and major bus corridors reinforces the creation of compact, walking distance, mixed-use communities linked by transit. This helps to reduce traffic congestion on freeways, preserve open space near urbanized areas, and improve energy efficiency. By creating mixed-use communities, Silicon Valley gives workers alternatives to driving and increases access to workplaces.
Low residential density is a sign of urban sprawl. After reporting 20 units per acre or more of newly approved residential development for five years, Silicon Valley's residential density fell until a recent uptick. Residential density reached 15.5 units per acre in 2012 and has increased 8.9 units per acre since a low of 6.6 in 1998.
Residential and commercial development near public transit reduces the usage of personal vehicles for transportation, decreasing road congestion and harmful emissions. The share of housing units approved near mass transit expanded to 82 percent in 2012, a 15-year high. This large jump from 2011 levels may be due in part to the expanded definition off transit oriented development from 1/4 mile to 1/3 mile in 2012. New housing units near transit totaled 3,619 in 2012, a 20 percent increase from 2011 levels.
In 2012, just over half (51%) of non-residential development was near transit. The net square feet of non-residential development near transit is lower than the previous year, though this is tied to a 31 percent drop in overall development levels.
Figure 67: Residential density increases to 15.5 average dwelling units per acre
Residential Density
Average Units per Acre of Newly Approved Residential Development
Silicon Valley
Note:
Beginning in 2008, the Land Use Survey expanded its geographic definition of Silicon Valley to include cities northward along the U.S. 101 corridor (Brisbane, Burlingame, Millbrae, San Bruno and South San Francisco)
Data source:
City Planning and Housing Departments of Silicon Valley
Analysis:
Collaborative Economics
Figure 68: Housing near transit shot up
Housing Near Transit
Share of New Housing Units Approved That Will Be Within 1/3 Mile of Rail Stations or Major Bus Corridors
Silicon Valley
* Beginning in 2012, the definition of transit oriented development has been changed from 1/4 mile to 1/3 mile.
Note:
Beginning in 2008, the Land Use Survey expanded its geographic definition of Silicon Valley to include cities northward along the U.S. 101 corridor (Brisbane, Burlingame, Millbrae, San Bruno and South San Francisco)
Data source:
City Planning and Housing Departments of Silicon Valley
Analysis:
Collaborative Economics
Figure 69: A great proportion of approved non-residential construction is near mass transit, while overall development falls
Development Near Transit
Change in Non-Residential Development Near Transit
Silicon Valley
Note:
Beginning in 2012, the definition of transit oriented development has been changed from 1/4 mile to 1/3 mile. Beginning in 2008, the Land Use Survey expanded its geographic definition of Silicon Valley to include cities northward along the U.S. 101 corridor (Brisbane, Burlingame, Millbrae, San Bruno and South San Francisco)
Data source:
City Planning and Housing Departments of Silicon Valley
Analysis:
Collaborative Economics