Flood in Malheur County, Oregon

Personnel from Boise WFO surveyed flooding on the Malheur River on Wednesday, February 26th. The river reached flood stage (19.5 feet) at Vale (VALO3) on Monday, February 24th around 9 pm and continued to rise into the major flood category reaching a crest of 23.55 feet around 12:00 pm MST on February 25th. The crest of 23.55 feet represents a stage above the USGS rating curve but estimated to be around 11,300 cfs, which is the highest flow since 1982. Observed impacts found by the NWS flood survey, conducted on February 26th, included some houses and outbuildings being impacted by flood water, especially in the vicinity of the 36th street bridge, in Ontario, Oregon. Significant flooding of agricultural land was observed near the river, extending as far as 1/2 a mile from the main channel on both sides of the river. There were several irrigation canals where water from the river breached head gates over filling the canals with flood water. At least one breach of the Nevada Irrigation canal side levy was observed which was causing additional agricultural flooding in an area separated from the main river flooding near Vale Oregon. U.S Highway 20, west of Vale, Oregon was inundated with flood water in several sections and remains closed as of 10 am, February 26th. It appears that the main levy protecting the city of Vale, remained intact through the flood. Information from the U.S. Army Corps of Engineers, indicated that any rise of water above 24 feet would have exceeded the safe design of the levee, and the observed crest of 23.55 feet remained below that critical threshold. There have not been any reported fatalities or injuries. The river has receded from the flood crest and fell below flood stage around 10 am, February 26th.

Warming temperatures and rain on snow events led to quick rises in the Malheur River. This led to several levee breaks near Vale, OR and caused agricultural flooding and nuisance flooding over Highway 20.