As part of Edmonton’s City-Wide Flood Protection Mitigation Assessment, AE created and modelled the storm and sanitary components of approximately 8,800 ha of residential developments located in North Edmonton. The model contained approximately 115,000 links (representing 3,000 km) including overland flow channels, storm, sanitary and combined pipes, ditches, culverts, natural watercourses, and catch basin leads.
Associated Engineering (AE) conducted a dual drainage study of the major and minor storm and sanitary system using a 1D-1D and a 1D 2D computer model to determine flood hazard areas, corresponding cost of flood damages, and design system upgrades to prevent future flooding.
Approximately 80,000 nodes were modelled consisting of storm, sanitary, and combined manholes, overland flow nodes, and catch basins. Additionally, about 14,000 catchments were delineated at a catch basin scale. The overland flow component was connected to the minor system and modelled in 2D using Mike-21. The improvement options were assessed using the City’s Level of Service (LOS) criteria based on using Hydraulic Condition Ratings and LOS objectives. Improvements to the system included upgrades to storage and conveyance systems supplemented by Low Impact Development techniques.
AE used proprietary topographical analysis and techniques in GIS to delineate the catchments to aid in building the large scale hydraulic model.