Sunrise at Fern Ridge Reservoir, one of three expected to fill up this spring. Photo by Bob Heims, U.S. Army Corps of Engineers.
With Willamette Valley snow pack way below average, and no extra rain in the forecast, the Army Corps of Engineers says most of the reservoirs it operates in the valley won’t fill up this spring.
We’re not anywhere near drought conditions. But the dry forecast means the Corps will have a tougher job managing how much water it releases and when. Releasing too much water now means there won’t be enough for salmon and other fish in the fall.
And boaters are sure to notice a difference.
Here’s where things stand, according to the Corps.
Willamette Valley snow pack is 40% of normal for this time of year. But snow pack is not a big factor, it only accounts for about 10% of the water in the reservoirs.
The main concern is over how much rain we’ll get this spring. Rain during April, May and early June is the primary source of water that fills these reservoirs. The information that the Corps is getting says spring and summer rainfall will be only 75% of normal.
That’s not so bad that it’s setting off alarms. But it does mean the Corps has started reducing water flows from reservoirs in the North and South Santiam basins. It may also have to reduce flows in other parts of the Willamette Valley. Corps spokesperson Amy Echols says these reduced flows are “less than ideal” for fish and water quality. But the Corps wants to make sure it has enough water stored to maintain good flows in the summer and fall.
Of the 13 Willamette Valley reservoirs operated by the Corps, only three of them are expected to fill up. They are Fern Ridge near Eugene, and the Cottage Grove and Dorena reservoirs near Cottage Grove.
“If you’re a boat owner or marina owner, you won’t like this year,” says Echols. She says levels in some reservoirs may be so low that some boat ramps won’t reach the water. Marinas may have to compensate by installing longer ramps. Anglers and other river users may notice lower water levels, too.
Still, Echols says, we’ve seen much drier years in recent history. 2001 and 2005 come to mind.
All of this could turn quickly with some good spring rains. The Corps plans to update this information in early May.
