INTEGRATIVE GIS AND MODELING TOOLS FOR LARGE CITY MASTER PLAN EVALUATION

The Metro Wastewater Reclamation District (Metro District) operates a transmission sewer system that services 20 member municipalities and 44 special districts in the greater Denver, Colorado area. This interceptor sewer system includes over 220 miles of pipe (ranging in size from 8 inches to 90 inches) and three main lift stations. The interceptors convey a daily average flow of 150 mgd to the headworks of the District's Central Treatment Plant. The Metro District has historically used steady state uniform flow analysis techniques coupled with a peaking factor equation derived from historical flow monitoring to evaluate the system. This approach did not take into account dynamic conditions in the sewer system that affect capacity and did not provide the Metro District with a flexible tool to plan for future growth within the service area. An integrative GIS and hydraulic modeling approach was taken to improve their current methods and upgrade their ability to plan effectively. The purpose of this paper is to summarize the approach taken in developing a custom Geographic Information System (GIS) tool to project wastewater flow rates (based on demographics and landuse) and constructing a dynamic hydraulic model to illustrate the benefits that these integrated tools provide the Metro District in master planning efforts now, and through 2020.