the film forum library tutorial contact |
Repairs Blocked Winter Fish Passage at John Day Damby Bill BakkeNW Fishletter, April 15, 2003 |
Repairs to the Oregon shore fishway at John Day Dam over the winter blocked the migration of some ESA-listed steelhead. According to ODFW's Ron Boyce, the adult fish ladder was shut down for needed repairs as requested by the state. He said the fishway was not passing fish properly; in some cases, they would hang up for weeks and not move through it. But exactly how long the ladder was inoperable is still unclear.
"There is some confusion about this, and it needs to be cleared up," Boyce said.
ODFW district fish biologist Tim Unterwegner said the ladder was closed from November 14 through April 3rd, but Boyce said he had heard it was closed from February 14 to March 3rd.
Unterwegner was not informed by his own agency that the ladder would be closed. He only learned about it from a state police wildlife officer who told him a lot of people were catching lots of fish below the dam. Not normally a "hot" fishery, Unterwegner heard that fishermen were catching ten fish a day per boat. And there were lots of boats.
Unterwegner also said he was never consulted about the timing of the fishway's closure. He was concerned about the ESA-listed wild steelhead headed for the John Day River. These fish normally move into the John Day in October and November, after river flows rise after the end of irrigation season.
The John Day River joins the Columbia about a mile above John Day Dam, so its water does not mix much with the Columbia. Rather, it sends a plume down the Oregon shore. During floods, Unterwegner said he has seen the John Day send a muddy plume out into the Columbia that stays on the Oregon side of the Columbia. Based on this observation, the ODFW biologist is worried that most of the John Day's wild steelhead were blocked when the fishway was shut down.
Unterwegner said that radio tags put into steelhead at Bonneville Dam have shown that steelhead move into the John Day River in November. "Twenty radio tags were put in fish and the first one was located in the lower John Day River in the first of November. These fish encountered cold water and it took them 120 days to move upstream."
In late April, the last radio tagged fish came through. He said the steelhead can travel 20 miles as day up the river as the water warms.
It is the unusual migration timing of the these fish that has Unterwegner most concerned, because the Oregon shore ladder was closed when he expected to see them move over the dam and into the John Day River. However, he said that there is no winter passage information from the Army Corps of Engineers to confirm their migration.
NOAA Fisheries fish passage program manager Gary Fredricks said that his agency has been trying for years to get the Corps to conduct winter passage counts because the window of opportunity for fishway repair is between November to March, a time when the fish ladders can be closed for a month.
In fact, at John Day Dam, Fredricks said the closures of the north and south ladders overlapped, creating a total migration block at John Day Dam over the winter for about two weeks. "Right now we are pretty much blind after November" when it comes to counts, he said. But the Corps has now agreed to begin tallying the fish.
According to Fredricks, the Oregon shore ladder was closed from mid-November to February 27th in order to complete the reconstruction of a fish passage problem that has been going on for eighteen years. "A new flow control section was created to solve a passage problem in the ladder," he said. "Steelhead would hold in the ladder and some would jump out." A net had been placed over the ladder but fish would still jump out and they were getting abrasions from hitting the concrete walls of the fishway.
ODFW's Boyce said "the fish just piled over the ladder" when the Oregon shore passageway was re-opened. Biologists say about 80 percent of the adult salmonids moving up the Columbia use that ladder, especially when there is no spill.
"I don't say it won't happen again," Unterwegner said, "but the work should have been delayed until January so that the John Day steelhead were not blocked."
learn more on topics covered in the film
see the video
read the script
learn the songs
discussion forum