Auburn, Calif. – In response to the King Fire, the Placer County Water Agency has mobilized an emergency project to manage the movement of charred debris from the burned watershed into the Rubicon River and PCWA Power System.
With saturated soils and heavy rains in the forecast this week, the project is being fast tracked to be ready for impending debris.
Agency officials are concerned that erosion and burned trees in the steep Rubicon River canyon will be loosened by heavy rains and wash into the river, PCWA’s Ralston Afterbay Reservoir and as far as the Middle Fork American River.
The area of concern ranges from PCWA’s Hell Hole Reservoir at the 4700-foot elevation down to the Ralston Afterbay Reservoir, which is just below the 1200-foot elevation. The current series of storms is predicated to bring heavy rains but little snow to these elevations.
“There are about 40,000 acres of burned land on the Rubicon River watershed,” said PCWA Director of Resource Development Andy Fecko. “This has the potential to create very serious impacts on our Power System and on downstream water supplies.”
Crews have been mobilized at Ralston Afterbay Reservoir by Syblon Reid Contractors of Folsom under a PCWA emergency services contract signed by the General Manager David Breninger under emergency authority granted by the Board of Directors in September.
Ross Hooper of the PCWA engineering staff is overseeing the debris management project. “We’re installing anchors and laying debris booms along the shoreline at Ralston today. We expect to pull them into place tomorrow,” he said on Tuesday afternoon (Dec. 2).
Officials hope the log booms will be able to contain any large logs that float down the river into the reservoir. In addition, the emergency effort includes a small fleet of heavy equipment and grappling gear to remove floating logs from the reservoir. The use of a heliboom is also planned.
All of the equipment was expected to be onsite and operational Tuesday and Wednesday, Hooper said. The effort is aimed at containing and removing the logs before they reach and possibly damage the Ralston Afterbay Dam. A plan is also in place to pass floating logs over the dam and collect them below.
The King Fire burned approximately 98,000 acres (153 square miles) of Sierra watershed Sept. 13 through Oct. 9. About 40,000 of these acres are along the Rubicon River watershed, a source of the PCWA Middle Fork American River Project.