Explore damage prevention information, local contacts and rules for safe digging in California.

One Call Centers

811 or


4005 Port Chicago Hwy
Suite 100
Concord, CA 94520



Advance Notice:

Minimum 2 working days with a maximum of 14 calendar days

Marks Valid:

28 days or when they are no longer reasonably visible
811 or


PO Box 77070
Corona,CA 92877


M - F 0600-1900

Advance Notice:

2 working days but not more than 14 calendar days

Marks Valid:

28 days

Legislative Information

yes Mandatory Membership
yes Civil Penalties
yes Tolerance Zone 24"
yes Hand Dig Clause
yes Mandatory Premark
na Emergency Clause
yes Positive Response
no Depth Exemption

Regional Partners

California Regional Common Ground Alliance

Geographic Location:

State of California


Randy Charland
California Regional Common Ground Alliance

Partner Since:

December 2004


To promote the use of the Common Ground Best Practices by encouraging stakeholders to accept and fulfill their shared responsibility in damage prevention; to welcome all stakeholders within our region and encourage their participation on this committee; to educate both committee members and non-members regarding Common Ground Best Practices; to identify issues concerning damage prevention within our region and attempt to construct practices to resolve them; to exchange ideas and information with other Regional CGA Committees. When a new damage prevention practice is created, the committee may forward the practice onto the appropriate CGA Committee for their consideration as a best practice. Our committee's efforts in damage prevention will help eliminate damages to underground facilities, interruption to vital services, safety risks, accidents and fatalities.