Too frequently, sewage disposal is thought of as synonymous with discharge into the nearest body of water. Such is not the case. Ultimate disposal (that is, final oxygen equilibrium) is inescapable and if it does not occur, at least partly, before the effluent is discharged, the sewage becomes a stream liability. The public is fast becoming impressed with the fact that it must, be concerned with this problem beyond the sewer outlets. There is a general awakening and a demand that something be done about the menace and nuisance of stream pollution. With advances in the knowledge and art of treatment permitting the reduction of almost any waste burden, the remedial problem is largely one of procedure and financing. If economy in efforts and funds were of no consequence, the problem could be solved simply by the invariable application of the highest and most elaborate treatment known. A sound and economical solution, however, requires an evaluation of pollution liabilities and stream assets, in advance of building, to permit the determination of the effect upon the stream of any proposed remedial program. In design it is highly important to give careful consideration to plant details and mechanical efficiency, but in the enthusiasm over the development of the “means” one should not lose sight of the “end.” First and foremost in importance is the effect of the design on the stream.