Yuba Water Agency Awards $13.9 Million Contract for New Colgate Slope Stabilization

en.Wedoany.com Reported - On September 1, the Yuba Water Agency in California, U.S., awarded a $13.9 million construction contract to Hat Creek Construction & Materials for slope and soil stabilization work on the hillside surrounding the New Colgate Powerhouse penstock. Construction is scheduled to begin in September and will proceed continuously as weather conditions permit.

This contract corresponds to the recovery efforts following the rupture of the New Colgate Powerhouse penstock on February 13 of this year. The incident involved a 14-foot-diameter penstock that conveys water from New Bullards Bar Dam to the New Colgate Powerhouse. Following the rupture, approximately 400 acre-feet of water flowed down the hillside, causing severe erosion around the penstock and damage to the New Colgate Powerhouse, multiple switchyards, and Lake Francis Road. Regulatory documents estimate that the incident also displaced approximately 265,000 cubic yards of hillside sediment.

The $13.9 million contract primarily includes the placement of slope and soil stabilization materials, the construction of a large rock buttress on the east side of the penstock, and the development of detention basins to manage rainfall runoff. Public bidding documents indicate that the work also involves localized grading and earthwork, temporary erosion and sediment control, drainage and runoff facility repairs, vegetation restoration, construction access improvements, and environmental protection measures. This contract covers temporary slope stabilization and erosion control work and does not include reconstruction of the penstock itself.

The Yuba Water Agency previously awarded GFT a penstock engineering design contract in May, with an initial amount of nearly $2 million, for pipeline condition assessment and repair options analysis. Subsequent detailed engineering design and construction support costs are expected to require an additional approximately $6 million. The final reconstruction plan and construction schedule for the penstock remain dependent on the condition assessment and incident investigation results, and a separate contract for pipeline reconstruction will be awarded at a later stage.

As a result of the incident, the New Colgate Powerhouse remains unable to resume power generation. The Yuba Water Agency stated that the plant outage could last for several years, and current recovery efforts simultaneously cover slope stabilization, penstock reconstruction planning, road repairs, powerhouse facility cleanup, and related infrastructure restoration. Funding for the $13.9 million stabilization project will come from the agency's own financial reserves.