Water in the headwaters of the main branch of Buffalo Creek has been contaminated by many years of acid precipitation and is unable to support aquatic life in the upper seven miles of the creek. In order to neutralize the acidic water and restore healthy conditions in the stream, a passive treatment system was completed near Buffalo Flat Road in the Bald Eagle State Forest in 2010. Stream water is collected and piped by gravity into two limestone basins where chemical and biological reactions increase its alkalinity and raise its pH level. The treated water then flows back into the creek, causing the water downstream to return to more normal pH readings. The fish, insects and other aquatic life that once thrived there are beginning to reappear.