Storm Drainage System Modeling of the Edmonton Clareview and Pilot Sound Storm Basins

The City of Edmonton operates and maintains over 5,000 km of sewer pipes. The collection system is made up of about 42% storm sewers, 39% sanitary sewers and 19% combined sewers. Storm drainage is captured and discharged to the North Saskatchewan River. Flows from the combined sewer area and the sanitary sewerage system are collected and discharged to the Gold Bar Wastewater Treatment Plant.

This paper presents the development and applications of the Clareview and Pilot Sound Storm Drainage Model. The study area is approximately 1,350 hectares and located on the north east side of the City servicing a population of about 18,000 mainly residential with portions of commercial, community services and industrial. A storm model was developed using DHI’s Mike Urban and Mike Flood to represent roughly 69 km of 1,200 pipes and 370 sub-basins within the study boundary. Pipe diameters vary from 200 mm to 2250 mm. The model also includes a pump station, five stormwater detention facilities and a number of flow diversion control structures. The objectives of the study include background data review and collection, field reconnaissance, development of model parameters and the drainage network, analysis of rainfall and flow monitoring data, calibration and verification of the model, assessment of the capacity constraints of the existing system under various storm events, evaluation of the performance of the stormwater detention facilities under severe storm events, determining system upgrade alternatives and the requirement for servicing the ultimate development stage/land use. The analysis also included a fully integrated and automated two-dimensional surface flooding model that connects the minor system (storm sewer network) with the major system (overland flow routes). Animation of the two-dimensional model simulation results were used to illustrate the extent of surface flooding within the study area.