Board hears options for dewatering Enloe

Submitted by sheilac on Wed, 07/24/2019 - 09:23

The Okanogan County PUD board authorized district staff to work towards developing a not to exceed price for the Enloe Dam right bank dewatering and safety inspection alternative.

Daniel Kuney, vice president of Max J. Kuney Company, shared four options for dewatering and inspecting Enloe Dam at a July 22 meeting of the board of commissioners. The inspection is required as part of ongoing dam safety monitoring.

The dewatering options analyzed, but not recommended, included diverting the river along the crest of the dam in sections with flashboards or sandbags, installing a siphon/pump system along the bank to divert the river around the dam, as well as installing a temporary dam upstream and utilizing pumps. However, all of these options are temporary, would require significant expenditures each time the dewatering method took place, had significant safety limitations and would not achieve all of the dam safety inspection objectives.

The recommended dewatering option Kuney presented was the right bank dewatering option, which would utilize the existing intake and rebuild it. New gates would open to new large diameter pipe (penstocks), diverting water through the right abutment, a process that could then be repeated at any time at minimal additional cost. This would allow for a larger timeframe to inspect, as well as future inspections, and the preliminary estimate is between $4-6 million, which will be subject to additional design and review before being refined.

Depending on what the inspection reveals, Director of Regulatory and Environmental Affairs Jeri Timm said the dam will likely need to be inspected in the future. Based on the findings of the initial dewatering inspection, the frequency will be determined by consultation with regulating agencies and dam safety engineers.

Kuney said the estimate has a broad range because his team is in the early stages of design and has many variables to work out. However, with the board’s direction, they will work toward finding the not-to-exceed amount for the right bank option. District staff will present that to the board, likely in October.

The anticipated timeframe for dewatering and inspection would be September-October 2020.

General Manager Steve Taylor said the district also received the expected letter from the Federal Energy Regulatory Commission, giving a 30-day notice of probable termination of the license for Enloe for failing to start construction of the project. This action was anticipated since the district decided not to electrify. A July 9, 2019, deadline had been set for beginning construction.

In other business, the board:

- Recognized two staff members with service awards.

    o Jered Mills marked 15 years with the district, starting as a groundman. In 2008, he was awarded the position of hazmat specialist, in recent years assisting the environmental department.

    o Brian Martin marked 20 years with the district, starting as a journeyman lineman. He later became a foreman, and is now the serviceman in Oroville.

- Approved resolutions 1691 and 1692, reflecting changes to bid limits after legislation this past session.