Yuba Water Recovering from Penstock Pipe Rupture

MARYSVILLE - Yuba Water Agency and environmental contractors continued recovery work this week following a catastrophic rupture of a penstock pipe on Feb. 13 between New Bullards Bar Dam and the agency's New Colgate Powerhouse, roughly 70 miles north of Sacramento.

The rupture released water from the penstock down a hillside and into the powerhouse. All but one personnel on site were safe following the incident, with one contract employee hospitalized for injuries. He is currently in stable condition, according to a Yuba Water news release.

The one-mile-long penstock pipe is a large pipe that connects to a five-mile-long rock tunnel at New Bullards Bar Dam and Reservoir. The pipe moves water between the dam and New Colgate Powerhouse for power generation. The facilities are part of Yuba Water's Yuba River Development Project, a multi-purpose flood risk reduction, water supply and hydroelectric power generation project to benefit the people of Yuba County.

"Our first concern has always been the wellbeing of the people involved, which is why I give today's update with a note of positivity, knowing that the people affected by Friday's incident are stable and on the road to recovery," stated Yuba Water General Manager Willie Whittlesey in a news release.

Yuba Water is working with environmental contractors and the California Department of Fish and Wildlife (CDFW) to contain and remove debris above the U.S. Army Corps of Engineers' Englebright Lake. Yuba Water is also coordinating with CDFW and others to assess the impact of the penstock rupture on the lower Yuba River, including the effect of temporary flow changes on aquatic species.

In the news release, Whittlesey emphasized that New Bullards Bar Dam, which is approximately five miles upstream of the incident site, was not impacted by the pipeline rupture, and that New Bullards Bar Reservoir has plenty of capacity to manage the current storms.

In addition to the ongoing environmental efforts, Yuba Water contracted a firm to conduct a LiDAR survey of the hillside around New Colgate Powerhouse. The data collected will be compared to prior LiDAR surveys and analyzed to better understand the impact from the incident.

Yuba Water continues to investigate the cause of the penstock rupture and has urged the public to stay away from the incident site while crews work to contain debris.

"We are turning the corner on this incident and are now working on a plan for the next few weeks and months," Whittlesey stated. "We recognize the seriousness of what happened and the impacts to our community and the Yuba River, and we're committed to a thorough and comprehensive investigation into exactly what occurred. We have a long road to recovery ahead, but we remain committed to rebuilding and continuing to serve the people of Yuba County."