A TMDL specifies the maximum amount of a pollutant that a water body can receive and still meet water quality standards and allocates pollutant loadings among point and nonpoint pollutant sources. Under section 303(d) of the 1972 Clean Water Act, states, territories and authorized tribes are required to develop lists of impaired waters. These impaired waters do not meet water quality standards that states, territories and authorized tribes have set for them, even after point sources of pollution have installed the minimum required levels of pollution control technology. The law requires that these jurisdictions establish priority rankings for waters on the lists and develop TMDLs for these waters.