Overview
- The Norton Fire began just before 5:30 p.m. Thursday near Nortonville Road and Black Diamond Way in the Black Diamond Mines Regional Preserve east of Clayton.
- Cal Fire initially estimated about 10 acres and later reported the blaze had grown to roughly 20 acres according to agency posts and local coverage.
- CAL FIRE’s SCU unit and Contra Costa County fire crews deployed significant air and ground resources and said firefighters were working to contain the grass fire.
- No structures have been reported threatened so far and the cause remains under investigation, though crews warned the blaze could expand to about 50 acres if conditions favor spread.
- Grass and vegetation fires can move fast on dry East Bay terrain so officials are maintaining aerial patrols and using social media to provide near‑real‑time updates as the situation develops.