A Total Maximum Daily Load (TMDL) is a regulatory term in the U.S. Clean Water Act, describing a value of the maximum amount of a pollutant that a body of water can receive while still meeting water quality standards. Alternatively, TMDL is an allocation of that water pollutant deemed acceptable to the subject receiving waters. TMDLs have been used extensively by the United States Environmental Protection Agency (EPA) and state environmental agencies in implementing the Clean Water Act by establishing maximum pollution limits for industrial wastewater dischargers. The Dudley Brook watershed is part of the larger Aroostook River watershed (HUC 0101004) in Maine and New Brunswick. It's headwaters begin in the Town of Castle Hill, Maine. The stream flows southeast through Castle Hill before terminating at its confluence with Presque Isle Stream just east of West Chapman Road in Chapman. Dudley Brook, designated a Class A stream, is approximately 6.4 miles in length and has a drainage area of 4,059 acres (1,643 ha). The entire length of Dudley Brook is classified as impaired according to Maines 2008 305 (b) list of waters that do not meet State water quality standards (Maine DEP 2008).