Lower Allegheny

Watershed Hydrology

The Lower Allegheny Watershed (HUC 05010009) covers an area of approximately 7,360 square miles in western Pennsylvania, Ohio, and New York. The hydrology of the watershed is influenced by the Allegheny River, which is the major surface water resource in the area. The watershed receives an average of 40-45 inches of precipitation annually, with about 50% of it falling as snow in the winter months. The snowpack typically accumulates from December to February, with the highest snowpack levels occurring in January. The reservoirs in the watershed serve as important sources of drinking water, recreation, and hydropower generation. Interesting climatic trends in the area include an increase in precipitation in recent years and an increase in frequency and intensity of extreme weather events, such as heavy rainfall and flooding.


Surface Flows

Lower Allegheny Watershed

Snowpack Depths

Lower Allegheny Watershed

Dams & Reservoirs

Lower Allegheny Watershed

Groundwater Levels

Lower Allegheny Watershed

Lower Allegheny Rivers

Rivers of the Watershed