The Lower Malheur Watershed covers an area of approximately 2,180 square miles and is located in eastern Oregon. The hydrology of the watershed is dominated by the Malheur River and its tributaries, with the main stem of the river flowing for 190 miles through the watershed. Snowpack in this area is typically light and melts quickly in the spring, with most of the water runoff coming from winter precipitation. Surface water in the watershed is used for irrigation and livestock watering, with several reservoirs providing storage for agricultural use. The reservoirs in the watershed contain primarily agricultural runoff constituents, such as sediment and nutrients. Interesting climatic facts include the area's arid climate, with average annual precipitation ranging from 7-15 inches, and the occasional occurrence of severe thunderstorms and flash floods. There is a trend towards increasing temperatures in the region, along with an increase in extreme weather events.