The Payette Watershed, located in southwestern Idaho, covers an area of approximately 4,700 square miles. The watershed is primarily mountainous, with the highest elevations exceeding 9,000 feet above sea level. Hydrologically, the Payette Watershed is dominated by the Payette River and its tributaries, which provide crucial water resources for the region. The watershed receives significant snowpack during the winter months, with snow water equivalent values often exceeding 30 inches in some areas. Surface water within the watershed includes several lakes and reservoirs, the largest of which is the Cascade Reservoir. This reservoir stores water primarily for irrigation and hydroelectric power generation. The water in the reservoir contains elevated levels of dissolved solids, including nitrogen and phosphorous. Recently, the area has seen an increase in average temperature and decrease in snowpack, potentially leading to increased risk of drought and wildfire.