Independent Spillway Team set to Review Oroville Dam
AGENDA 21 RADIO
BY PAUL PRESTON
By Risa Johnson, rjohnson@chicoer.com,
Sacramento >> The state Department of Water Resources gave the overseeing federal agency of the Oroville Dam what it asked for last week — a schedule for the independent review team investigating the cause of the spillway failures, but it listed no deadline for a final report from the team.
The Federal Energy Regulatory Commission told the state Department of Water Resources on March 20 to send the agency a schedule for its independent review team, approved by FERC, within five days. The department responded to FERC’s letter four days later, on Friday.
“Although DWR has gathered the information that will be needed for the team to review, the team is just beginning to digest the information,” wrote DWR Project Manager Ted Craddock in the letter.
The schedule for the team is to review materials from March 23 to April 12, conduct site inspections and meetings with DWR from April 12-13, have team meetings April 13-14 and provide a list of potential causes for the spillway failure to be factored into the design of the “interim spillways” in the first week of May.
From April 14 to an undetermined time, the plan is for the team to continue to review materials, do evaluations, hold meetings and complete evaluations, according to the letter.
Dates for the team to present its preliminary findings to DWR, the Division of Safety of Dams and the board of consultants and to complete its forensic report are to be determined, the letter said.
DWR UPDATE
DWR acting Director Bill Croyle told members of the press Monday in Oroville that spillway flows would gradually slow from 40,000 cubic-feet per second, or cfs, to zero cfs by late afternoon in order to do repairs.
“The process to step down has been revised, tweaked, (with) lots of consultation with our downstream water agencies, the flood operations center, our fish resource agencies — to make sure all the concerns everyone might have are factored into our revised plan,” Croyle said.
The department planned to restart flows at the Hyatt Powerplant, ramping up to about 11,900 cfs, and to increase outflows at the Thermalito powerhouse. One of the six turbines at the Hyatt plant remains unoperational, as it has for years. The department has said it is undergoing maintenance.
As of 6 p.m. Monday, Lake Oroville’s was at 836.5 feet of elevation, 64.5 feet below the lip of the emergency spillway. Though some experts say the completion date will be impossible to make, as reported by the Sacramento Bee newspaper, DWR is aiming for a ready-to-use spillway by winter.
“We will — if I have anything to do (with) it — have the spillway to use by Nov. 1,” Croyle said. “Whether that’s a permanent or temporary structure is yet to be decided.”
He said the spillway flows will be turned on again, likely when the lake rises to 860 feet.
Current projects include debris removal at the Diversion Pool, rebuilding roads to access the spillways, reinforcing the base and slopes of the spillway and inspecting the emergency spillway, where work is almost complete, he said.
Evacuation informational meetings for the public continue this week, with one in Palermo and one in Thermalito. Butte County Sheriff Kory Honea lifted the evacuation warning last week, though emphasized he wants residents to be prepared and stay informed. Residents can find their zone and sign up for emergency notification alerts at buttecounty.net/oem.
“Just because I lifted the warning doesn’t mean we’re out of this crisis,” Honea said.
