This report summarizes the Susquehanna River Basin Commissions (SRBCs) assessment of designated use support status of its basins rivers and streams. These assessments are based on monitoring activities from several water quality programs during the period 1996 to 1997. This report, which was prepared to meet the requirements of Section 305(b) of the Clean Water Act, is formatted according to the U.S. Environmental Protection Agency (US EPA) in its Guidelines for Preparation of the Comprehensive State Water Quality Assessments (305(b) Reports) and Electronic Updates (September 1997). The guidelines require the use of water quality, biological, and physical habitat evaluations to determine the degree of use support. The assessments made in this report represent updates to the assessment made in the previous 305(b) report, The 1996 Susquehanna River Basin Water Quality Assessment 305(b) Report, issued December 1996.