Bull Run Watershed

The Bull Run watershed is the primary source of water for Portland, Oregon. It is located in the Mount Hood National Forest, separated from the mountain itself by a ridge. The watershed is about 102 square miles in area, and typically receives 80-170 inches of rainfall per year. It includes reservoirs, which store water for use during the city's dry summer months.

The watershed is reserved solely for producing drinking water. The quality of its water is so high that the city does not treat or filter the water.