Abstract

The city of Detroit Water and Sewerage Department (DWSD) provides wastewater services for the city and 77 surrounding communities. A wastewater master plan (WWMP) has been developed for the department to provide guidance on sewer extensions and improvements that will be required to the regional collection and treatment system over the next 50 years. As part of the development of this plan, an analysis of wastewater flow needs has been completed for the city of Detroit and the surrounding communities. These flow needs have been defined in terms of wastewater flow rates that are projected to be generated within the system under both dry weather and wet weather conditions.

Wastewater flows for which projections are required are considered to consist of three components: (i) sanitary sewage flow, (ii) dry weather inflow/infiltration (DWII) or non-sewage flow, and (iii) wet weather flow (WWF). These three components are projected to future years separately, based on the factors that impact these flows.

Results have been used for evaluating potential capacity constraints of the regional system for the next 50 years. An additional goal of the analysis was to develop a uniform technical standard for assigning contract capacities for existing and new customers. This standard has helped to define what flows the regional system would be expected to accommodate versus what flows would be the responsibility of the customers to handle. Results of this analysis have been provided to the department for their use in future contract negotiations.

This paper is only available in PDF Format:

  View full text PDF