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Engineers struggle with balance between water levels and fish Mail Tribune / Drew Fleming Low water levels in the upper Rogue River are apparent at TouVelle State Park, where Rocky Point resident Steve Harvey prepares to fish on Friday afternoon. Engineers, worried by a dry winter, plan to cut releases from Lost Creek Lake into the Rogue to help save more water for use this summer. By Mark Freeman Faced with a woefully dry winter and no immediate prospects for heavy rains, authorities expect to cut Lost Creek Lake water releases next week to their lowest winter levels in seven years to help save more water for use this summer in the Rogue River. The U.S. Army Corps of Engineers might cut releases from the reservoir into the upper Rogue by 30 percent, a move Corps hydrologist Russ Davidson said will go "carefully to the edge" of flow levels needed for survival of wild spring chinook salmon eggs now incubating in the upper Rogue riverbed. The Corps, in conjunction with the Oregon Department of Fish and Wildlife, cut the out-flows similarly last week from Applegate Lake into the Applegate River. Cutbacks to the upper Rogue�s levels now will improve chances of filling Lost Creek Lake this spring, providing summer water to help feed the needs of fish, irrigators and others who rely on the extra Rogue summer flows. "If we�re going to have a dry summer, we need to do everything we can to fill (the reservoirs)," Davidson said. "We�re trying to cover all our bases and minimize our risks," Davidson said Friday. "But we think filling that reservoir is so important that we�re going to push to the edge." That edge likely means cutting outflows from Lost Creek dam from their current 1,000 cubic feet per second of water to about 700 cfs, the lowest the Corps can go under its authority granted by Congress in 1962. Davidson would not commit to a figure, but said that a flow of 700 cfs is "definitely not out of the ballpark." Cutting back that far risks a 5 percent loss of wild spring chinook salmon eggs now incubating in underwater gravel nests, called redds, along the upper Rogue, according to Tom Satterthwaite, an ODFW fish researcher in Grants Pass. Those 5 percent primarily are eggs laid by smaller female chinook in gravel closer to the river�s edge and in shallower water than the larger, more prized wild chinook, Satterthwaite said. "The real meat and potatoes of the run spawn in deeper water," Satterthwaite said. "They�re the ones we�re really zeroing in on and are trying to protect." Protecting wild spring chinook, a depressed stock that spawns in the upper Rogue, is the ODFW�s top fisheries priority for Lost Creek dam, which was built in 1977 jointly for flood control and enhancing fish populations on the Rogue. Spilling enough reservoir water now to keep from "de-watering" all the salmon eggs has to be weighed against having low, warm summer flows in the Rogue that can cause disease outbreaks that kill both migrating runs of adult spring and fall chinook. Such an outbreak killed three-fourths of 1992�s adult spring chinook run before the fish reached Jackson County. "We�d like to save all the (eggs) we could, of course," Satterthwaite said. "But it�s impractical to do that." The flow changes do not affect native coho or steelhead, both species that spawn in tributaries. Biologists and hydrologists are forced into this fishy conundrum because winter rains and snows have not yet materialized here. With snowpack and water content just half of normal through December in the Rogue and Umpqua basins, this region is considered the driest this winter in a state where midwinter water woes are common. The Corps typically starts filling Lost Creek Lake on Jan. 1, slowly rising the water level until it reaches full, usually shortly after May 1. But Lost Creek Lake remains about 3 feet below where it would be in early January for a normal year. At Applegate Lake, which the Corps officially starts filling each Feb. 1, water levels are about 16 feet lower than average. That prompted the Corps on Tuesday to cut releases to the Applegate River by 20 percent to 120 cfs, the lowest discharge level that would still protect wild fall chinook salmon eggs laid last fall in the Applegate riverbed. Despite the current dry conditions, there is still time for late winter and spring storms to restore the region�s snowpack enough that both Lost Creek and Applegate reservoirs would fill, Davidson said. But the prospects remain dim enough that Davidson believes cutbacks to the upper Rogue are past due for this winter. "I�m already remiss in my duties that I didn�t make a cut already," he said. Reach reporter Mark Freeman at 776-4470, or e-mail [email protected] Mail Tribune Home | Ottaway Newspapers, Inc. | Dow Jones & Co., Inc. | Privacy | Contact Us Copyright � 2000 Mail Tribune, Inc.