350 Bay Area Action and 350 Contra Costa Action strongly support Measure A – Contra Costa County Urban Limit Line

On November 6, 1990, Contra Costa County voters approved Measure C, the 65/35 Contra Costa County Land Preservation Plan Ordinance, which established mechanisms aimed at containing urban sprawl and protecting resources like agricultural land and scenic ridges. 

The most significant and impactful of these mechanisms are the 65/35 Land Preservation Standard and Urban Limit Line. Pursuant to the Standard, no more than 35 percent of the land in the county may be designated for urban uses (residential, commercial, industrial, etc.), and at least 65 percent must be designated for agriculture, open space, parks, and other non-urban uses. Meanwhile, the Urban Limit Line establishes a regulatory boundary beyond which no urban land uses may be designated. Together, these two mechanisms limit the geographic extent of urban development across the county. 

Measure C was set to expire in December 2010. In 2006, county voters approved Measure L, which carried forward most of the Measure C elements while adding provisions for periodic urban limit line review, establishing different processes for expanding the limit line by 30 acres or less and 30 acres or more. The provisions of Measure L are in effect through the end of this year*.

Measure A does a few things:

• It extends the Urban Limit Line (ULL) through 2051, adopting an updated ULL map;
• It requires voter approval (except in certain limited circumstances) to expand the ULL by more than 30 acres; and
• It retains the 65/35 Land Preservation Standard.

We feel it is critical to preserve open space and curb urban sprawl, while allowing mechanisms to adapt when truly needed.

* Source: 6/24/25 report from John Kopchik, Director, Conservation and Development, Contra Costa County, to Contra Costa County Board of Supervisors