Pend Oreille River flooding, high levels on Lake Pend Oreille expected

Published May 8, 2018

SEATTLE--Warm temperatures combined with above normal snow levels have created a situation where Pend Oreille River flows downstream of Albeni Falls Dam are likely to exceed flood stage this week.

The U.S. Army Corps of Engineers is releasing the full capacity of Albeni Falls Dam between now and when Lake Pend Oreille reaches the peak elevation for the year.  The normal maximum elevation for Lake Pend Oreille during the summer is between 2,062 and 2,062.5 feet above sea level. The lake could rise higher than normal summer elevation.

“Corps modeling using National Weather Service River Forecast Center hydrologic forecasts suggest we could see peak Lake Pend Oreille elevations ranging between 2,062.5 and 2,066 feet sometime between May 19-29, and outflows exceeding 100,000 cubic feet per second by May 11,” said Logan Osgood-Zimmerman, Upper Columbia Senior Water Manager for the Army Corps of Engineers. Lake Pend Oreille was lowered to the bottom of the one foot band at 2,051 feet above sea level before spring inflows began to rise. Albeni Falls Dam transitioned to free-flow April 29 and will remain on free-flow until further notice.

Albeni Falls Dam outflows are now completely controlled by the natural constriction between Lake Pend Oreille and the dam; outflows will vary gradually as the lake level varies. This free flow operation will allow Albeni Falls Dam to release the maximum flow possible, based on the natural constriction. The operation will reduce the eventual peak lake level, to the extent possible. It will also conserve space in Lake Pend Oreille, reducing the likelihood of releasing even higher flows downstream during the peak of the snowmelt event. Inflow to Lake Pend Oreille has been on a continued upward trend, as the warming spring weather increases snowmelt.

Lake elevations could be above 2,062.5 feet for several weeks.  Areas downstream of Lake Pend Oreille, such as Cusick, Newport, and Usk are likely to be affected by high river flows while the dam is on free flow.

Given the above normal snowpack and weather conditions, people residing in flood-prone areas should take precautions and be prepared for flooding.

USACE emergency management officials are providing sandbag training for local responders May 9 at 3 p.m. with the Kalispel Tribe of Indians at the Kalispel Tribal boat launch in Pend Oreille County, Washington; and May 10 at 5:30 p.m. with Bonner County at the Selkirk Fire Department, 2689 Gun Club Road, in Sagle, Idaho.

The seasonal water supply forecast for April-July inflow volume is 150 percent of average, and snowpack in the Pend Oreille basin is above average. The National Oceanic and Atmospheric Administration forecast is for continued warm weather with some shower activity.

The Corps is closely monitoring weather and snowpack conditions, lake inflow, forecasted releases, and the level of Lake Pend Oreille. The Corps will continue to operate Albeni Falls Dam to minimize flood risk.

Short term modeling forecasts are provided by the Northwest River Forecast Center. Their projections for Albeni Falls Dam inflow, outflow and the Lake Pend Oreille at the Hope gage can be found here:

Projections for future operations at Albeni Falls Dam can be found here:


Public Affairs Office

Release no. 18-030