Preliminary HNTB review finds power-transfer failures behind Richmond water plant outage; city outlines equipment, staffing and SOP changes

A preliminary review by engineering consultant HNTB concluded the Richmond water treatment plant suffered a complete loss of power after a bus-tie failure prevented transfer from the primary feed to the secondary feed, hitting the plant’s winter-mode configuration and contributing to a nearly 36-hour outage, consultants told the Governmental Operations Standing Committee.

That finding, delivered during a committee presentation, said the plant’s effluent valves were not closed by the site’s uninterrupted power supply and on-site diesel pumps were insufficient to prevent basement flooding that damaged equipment. “The water treatment plant experienced a complete loss of power,” the HNTB presenter said during the meeting.

Why this matters: Committee members pressed city staff about why the plant had been operating in a “winter mode” that HNTB said left the facility with a single point of failure. Staff told the panel the utility will operate the plant in a “summer mode” going forward to provide built-in redundancy and reduce the risk that a single component failure will cut power to the…