https://www.siliconvalley.com/2021/03/12/contra-costa-county-to-move-to-red-tier-as-state-hits-covid-vaccine-goal/

A rules change coupled with improving COVID-19 numbers led California to authorize a major economic reopening Friday, with 13 counties — including Contra Costa — moving into the more permissive red tier.

The shift came as the state hit a goal Friday of vaccinating 2 million people in underserved communities hardest hit by the virus, and — as previously promised — relaxed its reopening rules.