It is generally recognized that the Black Warrior River is a classic example of unrestricted use of a stream as a receiving body for the disposal of sewage and industrial wastes. A section of this river, in the vicinity of Tuscaloosa, Alabama, has been selected for this presentation. The area studied begins upstream at Holt Lock and Dam, river mile 347.5, and has a downstream limit of river mile 309.5 which is four miles below the mouth of Cypress Creek. These limits were selected because they cover all significant pollutional effluents received by the Black Warrior River in the Tuscaloosa area. Another unique factor concerning these limits is that the relative quality of the water both upstream and downstream of these limits is good while portions of the area to be considered are grossly polluted--especially during periods of low flow.