A report compiled by a federal agency questions the need for two major dams on the Yuba River due to their harmful impacts on three distinct native fish populations.
In the report, released last week, the National Marine Fisheries Service ordered the United States Army Corps of Engineers to do more to provide for better fish habitat on the South Fork of the Yuba River.
The opinion said the operation and maintenance of DaGuerre Point Dam and Englebright Dam detrimentally impact the populations of three endangered species of fish - Spring-run Chinook Salmon, Central Valley Steelhead and Green Sturgeon.
All three are on the endangered species list and use the Yuba as critical habitat and breeding ground, the Fisheries Service report stated. The decision was issued in part as a result of a lawsuit filed in 2006 by the South Yuba River Citizens League and Friends of the River.
The new biological opinion is an important first step toward preventing the extinction of Yuba River salmon, steelhead and sturgeon," said SYRCL Director Caleb Dardick. "These endangered fish need to be able to move freely upstream of DaGuerre Point and Englebright dams to the upper Yuba River watershed."
The opinion asks the Corps to contemplate a full range of solutions to the detrimental impacts the dams are having - including destruction of the dams, modification of the dams or alternatives such as collecting the fish and transporting them via truck.
"The (Corps) need to address the impacts," said Gary Sprague, a fish biologist with the Fisheries Service. "The fish populations are in very bad shape."
Corps spokeswoman Dede Cordell, however, said the opinion "directs activities that are not within our authority."
"Both Englebright and DaGuerre Point dams are authorized by Congress for the purpose of controlling debris that could disrupt river navigation," she said. "Any change to that purpose - including fish passage at Englebright or dam removal - would require additional authorization by Congress."
However, Cordell said the Corps is willing and ready to conform to certain short-term aspects of the order, including installing more gravel and woody debris in and around the river to facilitate better spawning habitat. Both operations are expected to commence this summer, Cordell said.
"We think it's important to note that we are doing everything within our authority to help these species recover," she said.
Cordell said destruction of the dams could have unintended consequences, including releasing thousands of tons of mining debris collected when mining operations were active in the region. Englebright Dam was built in 1941 for the primary purpose of capturing sediment from nearby hydraulic mines.
Sprague said sediment levels and their potential impact would have to be analyzed before destruction could be considered a viable method of restoring the fish populations to healthy levels.
Currently, DaGuerre Point Dam - Yuba County's 24-foot dam built in 1906 - features a fish ladder to effect passage, but Sprague said it was outmoded and inefficient, particularly for sturgeon which are behaviorally opposed to navigating the contraption.
Furthermore, salmon and steelhead are delayed at the dam and while some members of the species do successfully make it upstream, the delays are significant and detrimentally impact breeding.
Englebright Dam, which is more than 200 feet tall, is not amenable to such fish passage systems as fish ladders.
"Fish ladders have proved unsuccessful in dams of that size," Sprague said.
Gary Reedy, Fisheries biologist and science director for SYRCL, said full removal of the dams would be the most effective way of restoring fish populations to the Yuba.
"The new requirements include a variety of helpful short-term measures, and yet full fish passage is what is needed to actually avoid the substantial harm to the survival and recovery of the species being caused by DaGuerre and Englebright dams, as the biological opinion concludes," Reedy said.
Reedy and Dardick identified the opinion's requirement that the Corps to implement a program that facilitates fish passage past the dams by 2020 as one of the most important items in the report.
The Corps will analyze the opinion and provide feedback to the Fisheries Service within the next 30-45 days regarding compliance limitations, Cordell said.
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