The Upper Elkhorn watershed covers an area of approximately 2,310 square miles in north-central Nebraska. It is a part of the larger Missouri River Basin and is characterized by rolling hills and grasslands. The hydrology of the watershed is dominated by surface water with numerous streams and rivers flowing through it, including the Elkhorn River. The area experiences significant snowpack during the winter months, which contributes to streamflow during the spring and summer. The surface water in the watershed is used for irrigation and recreation, with several reservoirs located within the watershed. These reservoirs contain sediment and nutrients, which can impact water quality. The area experiences a semi-arid climate, with average annual precipitation of approximately 22 inches. Over the past century, the area has experienced warmer temperatures and an increase in extreme weather events such as drought and flooding.