Regional engineer had raised alarm about condition of spillway gates
By Erik Robinson
Federal energy regulators say they’re satisfied with PacifiCorp’s plan to repair spillway gates at three major dams on the North Fork of the Lewis River.
The regional engineer for the Federal Energy Regulatory Commission last month raised alarm about the condition of the gates. FERC Regional Engineer Patrick J. Regan in Portland, in a letter dated June 2, summarized a series of concerns with the findings from a 10-year inspection report conducted by PacifiCorp and submitted to the federal agency earlier this year.
FERC and PacifiCorp declined to release the report itself, citing security concerns.
Regan, in a letter dated June 2, reacted publicly to the inspection’s findings, which he summarized by noting missing or broken bolts and rivets, out-of-plane bending and cracked welds.
The condition of the spillway gates caused Regan to question "whether these gates should continue to retain water.”
A FERC spokeswoman said this week that PacifiCorp has allayed the agency’s immediate concerns.
"What they’ve done right now is an interim step that has satisfied the concerns we had in the letter,” Celeste Miller, a FERC spokeswoman in Washington, D.C., said Tuesday. "The long-term remediation program … will look at addressing all of the concerns raised in that letter.”
She said the company had replaced bolts and fasteners on the five spillway gates at Merwin. She added that the utility also lowered the reservoir by 2 feet to remove some of the water pressing against the spillway gates.
"No recreation sites or boating opportunities are affected,” Miller said in a follow-up interview Wednesday. "This is just done to be cautious, to err on the side of caution.”
PacifiCorp spokesman Tom Gauntt in Portland said Wednesday that workers will remain at Merwin Dam through today to apply a coat of paint. He said that the reservoir was lowered 1½ feet "to prevent possible high winds from splashing any water or debris over the top of the gates while the maintenance work was going on.”
"Our structural engineering consultant has declared all of the Merwin spillway gates to be fit for normal duty,” Gauntt wrote in an e-mail.
Gauntt said the company’s structural engineers began their inspection of the five spillway gates at Yale Dam on Wednesday, and they plan to complete the inspection of Yale and the two spillway gates at Swift Dam by Monday.
"PacifiCorp is prepared to immediately pursue repair work at these facilities if any condition is found that requires a near-term response,” Gauntt wrote.
Regan, in his June 2 letter, indicated many spillway gates were in such poor condition that they could fail suddenly.
"Some of these findings seem a cause for great concern,” Regan wrote in the letter addressed to PacifiCorp Energy official Randy Landolt. "For instance, at Merwin, loss of enough rivets or bolts near a trunnion could cause a catastrophic failure of the gate.”
Erik Robinson: 360-735-4551, or email@example.com.