How big is the contra costa county fire protection district? Contra Costa County Fire Protection District. Our District is a recognized fire service leader, one of the largest in the State of California, providing fire and emergency medical services to nearly a million people across a 804 square-mile area in and around the 19 cities of the county.How do i report a fire or medical emergency in contra costa? We would like to hear your feedback. Please fill out this form. For a fire or medical emergency in Contra Costa County, dial 911, or (925) 933-1313 from cell phones or outside the county.How do i call 911 in contra costa county ca? For a fire or medical emergency in Contra Costa County, dial 911, or (925) 933-1313 from cell phones or outside the county. The Administrative Offices include the following CCCFPD Divisions: Administrative Services, Emergency Operations, EMS, Fire Prevention, Information Services, and Support Services.