Section 303(d) of the federal Clean Water Act (CWA) and the U.S. Environmental Protection Agency's (EPA) implementing regulations direct each state to identify and list waters, known as water quality limited segments (WQLSs), in which current required controls of a specified substance are inadequate to achieve water quality standards. For each WQLS, the State is to either establish a Total Maximum Daily Load (TMDL) of the specified substance that the waterbody can receive without violating water quality standards, or demonstrate that water quality standards are being met. The Lower North Branch Potomac River (basin code 02-14-10-01), located in Allegany County, Maryland, was identified on the States list of WQLSs as impaired by low pH (1996 listing), nutrients (1996 listing), sediments (1996 listing), cadmium (Cd) (1996 listing) and impacts to biological communities (2002 listing). This report provides an analysis of recent monitoring data to address whether the low pH impairment still remains. A data solicitation for pH was conducted by MDE and all readily available data from the past five years was considered. The study demonstrates that the applicable aquatic life criterion for pH and the designated uses supported by this criterion are being met in the Lower North Branch Potomac River.