The Upper Skagit Watershed (HUC 17110005) covers approximately 1,370 square miles in northwest Washington State. The watershed is fed by precipitation, and its hydrology is heavily influenced by snowpack accumulation in the winter months. The snowpack provides a significant source of surface water during the warmer months, which supports a diverse range of aquatic and terrestrial ecosystems. The Skagit River, which flows through the watershed, is home to several hydroelectric dams and reservoirs that regulate the river's flow and support the region's energy needs. The watershed experiences a maritime climate, with mild winters and cool summers. Climate change has led to a reduction in the snowpack and an increase in winter precipitation, which could have significant impacts on the region's hydrology and ecology in the future.