VALE, Ore. -- Flood risk management releases from Malheur Basin Reservoirs are planned to resume as early as Thursday, Feb. 27.
Releases from Warm Springs, Agency Valley, and Bully Creek reservoirs were turned off to 0 cubic feet per second (cfs) this past weekend in advance of anticipated high downstream runoff from a rain-on-snow event. The goal of this operation was to allow peak flows to pass through Vale without additional release flow from the reservoirs worsening flood conditions.
Peak flows passed through Vale on Tuesday, Feb. 25 where a stage of 23.6 feet was reported at the Vale United States Geological Survey (USGS) gauge. Major Flood stage is defined as a threshold of 23.0 feet. Flows have currently receded to the Moderate Flood category, with active flood fighting ongoing. Inundation is being observed throughout much of the basin, including water covering farmland, infiltrating some buildings, and blocking and damaging many roads and other infrastructure.
Flows will continue to recede throughout the next several days. Although much of the low elevation snow was melted off with this event, there is still a nearly record setting snowpack above the reservoirs. Reservoirs will need to resume releases in anticipation of future snow melt and runoff entering the reservoirs.
For this round of reservoir releases, managers will coordinate the timing of flows to be at or below the Moderate Flood threshold of 21.0 feet. These releases are intended to reduce the risk of future high peak flows during the spring runoff season, while also not exacerbating downstream flood damages from naturally occurring runoff. Future reservoir releases may need to be above or below the Moderate Flood threshold, depending on real-time basin conditions throughout the end of winter and spring.
Officials advise the public to be aware of risks associated with flood season. Even below flood stage, the water is deep, cold and fast. Extreme caution should be used near the riverbanks.
River stage is recorded on the Malheur River below the Nevada Dam near the Vale USGS gauge. For more information on this gauge, visit: https://water.weather.gov/ahps2/hydrograph.php?gage=valo3&wfo=boi.
For current river flow and water storage information, visit https://www.usbr.gov/pn/hydromet/owytea.html.