Storage-Treatment Mixes for Stormwater Control

A methodology to estimate the cost of controlling pollution from urban storm related discharges is presented. This procedure was used to assess pollution from combined sewer overflows and stormwater runoff for each of the 248 urbanized areas in the United States and for a similar assessment in Ontario. Generalized predictive equations are developed, to determine the optimal combination of storage and treatment for a set of assumed costs, based on relatively intensive studies of five cities: Atlanta, Denver, Minneapolis, San Francisco, and Washington. The first section describes the available storage-treatment options—their costs and effectiveness. Then, the production functions relating pollution control to storage and treatment are described. The solution to the problem of finding the optimal mix of storage and treatment for any level of control is presented next. Lastly, a sample application to a hypothetical United States city of 1,000,000 is shown to illustrate the methodology.