The Little Lost Watershed (HUC 17040217) covers an area of approximately 500 square miles in central Idaho. The watershed is primarily fed by snowmelt from the surrounding mountain ranges, with the snowpack typically peaking in early April. The Little Lost River is the main surface water feature in the watershed, and it flows into the Mackay Reservoir, which is used for irrigation and recreation. The reservoir also contains significant amounts of sediment and nutrients, which can lead to water quality issues. The area experiences a semi-arid climate, with relatively low precipitation and high evapotranspiration rates. In recent years, there has been a trend of decreasing snowpack and earlier snowmelt, which may have significant impacts on water availability and ecosystem health in the watershed.