Pennsylvania has approximately 83,000 miles of streams and rivers. In order to fulfill monitoring requirements of the CWA, a process was needed to evaluate wadeable streams on a local scale while progressing towards a complete statewide assessment of Pennsylvania water quality in a timely manner. To meet this end, the Department of Environmental Protection (DEP) first implemented Pennsylvania State-wide Surface Waters Assessment Program (SSWAP) in 1997. This program, (formerly referred to as the Unassessed Waters, or UW Program) was designed to:
conduct stream assessments as quickly and effectively as possible,
complete a state-wide assessment of all streams within 10 years,
document Point Source and NPS impairments state-wide, and
identify the causes and sources of these impairments.