[env-trinity] Trinity Journal- BOR plans increased flows on Trinity River

[Tom Stokely]

http://www.trinityjournal.com/news/environment/article_78a0a716-d601-11e1-8a29-001a4bcf6878.html 
BOR plans increased flows on Trinity River
By Amy Gittelsohn The Trinity Journal | Posted: Wednesday, July 25, 2012 6:15 am
The U.S. Bureau of Reclamation has plans to boost flows to the Trinity River in the late summer -- beyond what had been scheduled -- to reduce chances of a fish die-off in the lower Klamath River.
The agency recently released a draft environmental assessment and finding of no significant impact for the plan to release an additional 48,000 to 92,000 acre-feet of water to the river from Aug. 15 to late September. The comment period on the documents ends Friday.
The Trinity River is the main tributary to the Klamath, which in September 2002 saw a die-off of fall chinook salmon due to disease resulting from overcrowding during the large fish run, warm water, and low water velocities and volumes.
Different estimates have been given for the number of fish that died prior to spawning in 2002, many of them bound for the Trinity River. At Reclamation, "our official estimate is 34,000," said Reclamation spokesman Pete Lucero. Some other estimates were almost twice that much.
The water year ends Sept. 30, so the additional release to the river would not affect Central Valley Project water deliveries for 2012, Reclamation said.
The higher release could affect carryover storage at Trinity reservoir and cold water available for fish in 2013.
"We don't know for sure if we're going to have an effect on future years until we know what our hydrology's going to be," Lucero said.
The environmental assessment notes that while available water supplies in the Trinity River Basin increased dramatically in the spring, the water supply in the upper Klamath River didn't improve nearly as much.
With a fall run of 352,000 fish expected this year, which would be the largest on record since 1978, and relatively dry conditions in the upper Klamath Basin, biologists have been concerned about a repeat of 2002.
An additional 48,000 acre-feet of water released to the Trinity River is proposed to avert that. Another 44,000 acre-feet could be released to increase the water turnover rate if high levels of fish-borne illness are detected, according to the assessment.
Under the proposed plan, releases from Lewiston Dam to the Trinity River will be increased from Aug. 15 to Sept. 21 or 30 depending on water temperature, a time period at which the release would normally be 450 cubic feet per second. The goal would be to supplement flows in the lower Klamath so they are 3,200 cfs rather than approximately 2,575 to 2,800 they would be with no changes to the Trinity flow.
A higher pulse flow is planned on Sept. 2, coinciding with a higher release from Iron Gate Dam on the Klamath River for a Yurok Tribe ceremony. The pulse flow of 4,400 cfs in the lower Klamath would further increase water velocity and turnover rates in parts of the river where adult salmon are holding, Reclamation said.
While the release at Lewiston would be dependant on the Klamath flow and tributaries in order to hit the target in the lower Klamath, a hydrograph in the assessment indicates the Lewiston release would increase to about 1,000 cfs in August with a spike in early September of around 1,400 cfs, returning to 1,000 cfs and then back to 450 cfs.
From the Trinity Lake Revitalization Alliance, Kelli Gant said she feels torn about the plan. If the entire 92,000 acre-feet is taken from the lake, "it's about a 7-foot elevation change," she said.
"You're torn because you understand the need for the fish but then again I don’t know if it's that big of a crisis," Gant said. "Show us the science that says this is needed."
"Our fear is they're going to release all that water and then we'll have another dry winter like the last one," she said.
Tom Stokely, water policy analyst for the California Water Impact Network and a former Trinity County natural resources planner, agrees with the plan to release more Trinity water.
"It's the right thing to do," he said, "and I don't think anyone wants to be responsible for another fish kill like the one in '02."
While it's true that a 3,200 cfs flow in the lower Klamath would be rare under natural conditions, Stokely said "it's not a natural system on either side, anymore."
In addition to the dams, erosion from human activities has filled in deep holes fish used to hold in, he said, and the huge salmon run anticipated plus poor hydrology on the Klamath side are good reasons to take the action.
"I hope nobody decides to challenge it legally," Stokely said, "because the consequences could be devastating."
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www2.dcn.org/pipermail/env-trinity/attachments/20120725/a411ef4d/attachment.html>