Lines on the Land: The Urban Limit Line in Contra Costa County

One of the most important and powerful tools communities have for managing growth stopping sprawl development is the Urban Limit Line, or ULL (also known as an Urban Growth Boundary in some parts of the region). A ULL is the legally-protected line in the sand beyond which sprawl development is stopped in its tracks. Inside the ULL, urban services can be connected and all sorts of residential and commercial zoning is allowed, but just beyond it, development is severely restricted. This land beyond the ULL helps form the Bay Area’s greenbelt.

In Contra Costa County, priceless ecological gifts like the County’s acres of prime agricultural land and the critical wildlife habitat on the slopes of Mt. Diablo have inspired County residents to fight for its protection.

In 1990, voters approved Measure C-1990, which created a guarantee that at least 65% of land in the County would be preserved for agriculture, open space, wetlands, parks and other non-urban uses, and that no more than 35% of land would be used for urban development. In order to implement this “65/35” standard, the County established a ULL, which clearly defined where urban development was welcome, and where it was not.

Voters gave some extra teeth to the ULL in 2004 by voting for Measure J. In order to receive money from a transportation tax in the County, each city either had to adopt the County’s ULL or obtain voter-approval for their own ULL. The incentive worked, and all cities approved a ULL–only Pittsburg, Antioch, and San Ramon approved a ULL different from the County’s. Voter-approval is clutch and not all ULLs in the Bay Area require it–but a voter-approved ULL is a much safer protection than a city council-controlled one.

Contra Costa once again doubled down on the ULL in 2006 by voting for Measure L, extending the 65/35 designation and the Urban Limit Line until 2026. In 2016, the County did an extensive study to determine whether it could meet its housing and jobs needs within that boundary through 2036. The conclusion was a resounding yes.

These tremendous victories for quality of life and open space were not a foregone conclusion. It was the tireless, patient effort of our community of open space advocates that ensured good decision-making. This is not the first time Brentwood has faced challenges to its ULL, and every time a developer threatens to undermine our City’s value, voters come back with a hard no. We worked in 2006 and again in 2010 to stop ballot measures seeking to expand the City–and we’ll do it again.