News Release
| Release Number: | 01-023 |
| Dated: | 3/2/2001 |
| Contact: | Matt Rabe, 503-808-4510 |
Portland, Ore.-- Reservoirs in the Willamette Valley are filling very slowly this year because of little rainfall between the Coast and Cascade mountain ranges.
The question on everybody's mind is: Just how full will the reservoirs get?
Although nobody has a very clear answer to that question, the U.S. Army Corps of Engineers will host a series of meetings designed to explain what is happening at its 13 Willamette Valley multi-purpose reservoirs, what reservoir and river users can expect this year, and how decisions about reservoir management are made.
Two sets of meetings will be held: the first series in March will provide an outlook of projected reservoir levels and seek public input, the second in April will lay out how the system will be operated based on forecasts and operating criteria. Meetings will be held March 13 at the Comfort Suites, 969 Kruse Way in Springfield, March 14 at Sweet Home High School, 1641 Long St. in Sweet Home, and March 15 at Stayton High School, 757 W. Locust in Stayton. Each meeting will begin at 7 p.m. and will conclude with a discussion and question period. The dates and locations of the April meetings will be announced later this month.
The Northwest River Forecast Center reports that observed precipitation in the Willamette Valley for the month of February was 2.28 inches, or 35 percent of normal. Observed precipitation for the water year (Oct. 1 through Feb. 27) is reported at 19.16 inches, or 50 percent of normal. As of midnight Thursday, reservoir levels were about 29 percent below normal.
Using current weather conditions and computer models, the results show it is unlikely that any of the reservoirs will be full by Memorial Day weekend. The models also show many of the reservoirs will miss their normal summer levels by many feet and will lower faster than normal during late summer.
"The Willamette Valley is mostly a rain driven system," said Matt Rabe, public affairs specialist for the Corps' Portland District. "The longer we go without any significant rain, the less opportunity there is to fill the reservoirs."
In addition to filling the reservoirs for summer lake users, the Corps also must release water from the reservoirs to meet downstream requirements. Those include streamflow augmentation for fisheries, navigation, water quality and irrigation.
Water must be released at various times of the year to ensure adequate stream conditions for migrating and spawning fish from April through June, and water quality standards from June through September. Summer and fall water releases support navigation by maintaining minimum depths in the Willamette River between Albany and Salem.
"We are working with the Oregon Water Resources Department, National Marine Fisheries Service, and the U. S. Fish and Wildlife Service to determine how much water needs to be released for various uses, when and for how long," said Rabe.
Decisions that balance the competing uses are made each year when determining how to manage the water in the Corps' reservoirs. During low-water years, however, this decision-making process becomes increasingly difficult and reservoir managers need to look at all the available options before setting a course of action.
"Those decisions will determine how full the reservoirs will get this year and how long we will be able to hold them at those levels," said Rabe.