Hoopengarner on Outdoors
509-582-1544
Dams should help keep boaters afloat
The grounding of a passenger cruise ship during March on the Columbia River south of Finley should serve as a caution buoy for recreational boaters this season.
With water levels that can fluctuate several feet in a few hours on the Columbia and Snake rivers, it's a good idea for Mid-Columbia recreational boaters and anglers to keep an eye both on the horizon and on the depth finder.
Despite the forecast of drought this summer, Al Sutlick, a wildlife biologist with the Army Corps of Engineers' Operations Division in Walla Walla, said that because water levels behind Snake and Columbia river dams only fluctuate a few feet in normal daily operations, all boat ramps, marinas and park swimming areas should be usable through the summer.
Sutlick explained that Snake and Columbia river dams have no flood control capabilities and are operated for hydroelectric power and navigation only. They are referred to as "run of the river dams."
"We can only hold water behind a dam for a few hours before we have to release it for hydro generation," he said. "In any given day, though, there could be spots on the river that might pose a problem for boaters, but that's always been the case.
"I really don't think we're going to have any problems on the Snake unless we simply run out of water for barge navigation. And that's never happened before," he added.
Snake and Columbia river dams, he said, generally try to maintain reservoir levels within a 3- to 5-foot window. At McNary Dam, for example, the operating level is 337 to 340 feet above sea level, with typical daily operations in the 338 to 339 range.
Because of our mild weather and lack of snowmelt, water flow on the Snake at Ice Harbor Dam averages about 65,000 cubic feet per second (cfs). During the high-water runoff that occurred a few years ago, spring flows on the Snake hit 150,000 cfs.
"In a normal year, the flow on the Snake about this time of the year should be about 75,000 cfs or higher," Sutlick added.
Julie Ammann, a hydraulics engineer with the Corps' reservoir control center in Portland, said flows should be increasing on the Snake during the next few weeks - perhaps reaching 75,000 cfs.
"The warm weather we've been having will certainly trigger snowmelt in the mountains, but the increase in the flow likely will not be as much as we normally see," she added.
And once the spring runoff has passed, Ammann said she expects to see summer flows on the Snake as low as 18,000 to 20,000 cfs.
At McNary, the peak spring runoff flows are excepted to hit about 100,000 to 180,000 cfs, with late summer flows at less than 90,000 cfs. Flows at McNary are usually about 135,000 cfs.
"Recreation-wise," she said, "the reservoirs behind the Snake dams should be fairly stable this year, unlike many other areas in the Northwest, such as on the upper Columbia.
"If the barges can make it down the river, then recreational boaters should be able to use any of the Corps' boat ramps and marinas," she added.
However, Ammann said that because of low water supplies from the limited snowpack, the Columbia's flow at Vernita and in the Hanford Reach likely will be lower than normal this year. That could pose problems for mariners. But Corps officials anticipate being able to operate Priest Rapids and McNary dams within their normal operating ranges.
Sutlick said 2001 is shaping up like the low-water year of 1988, when flows on the Snake hit 13,000 cfs during the summer.
"Fortunately, we still had enough water to offset natural evaporation, which on a very hot day could cause the loss of perhaps an inch of water from the system," he said.
"I think the biggest thing anglers, boaters and water skiers might notice this year will be slightly warmer water and perhaps cloudy water from increased algae and other microscopic organisms."
The Corps conducted a study a few years ago on operating its Snake River facilities based on the lowest possible flows.
"What we found was that there wasn't anything we couldn't access or use," he said.
Sports home | Americans | Posse | Area sports | Riley | Outdoors | Area golf