As part of their modernization program, the Canada Post Corporation planned the construction of a new 6550 sq.m. state of the art letter carrier depot at the site of an existing Canada Post truck repair facility located in the waterfront area of Toronto. The project included for an architectural design in keeping with this politically sensitive area of Toronto including an exterior “nautical theme’. The project was targeted to achieve LEED Gold accreditation.
MGM Consulting provided the project architects with the preliminary and detailed design of storm, sanitary and water servicing for the site, site grading design, parking layout, and stormwater management design as required to achieve the Wet Weather Flow Management objectives as established by the City of Toronto, and as required to achieve LEED credits for rate and quanity control, and quality control.
Site grading was designed to the specific requirements of Canada Post as required to provide vehicular and pedestrian access to the site. Site grading also needed to take into account the high ground water table and flooding potential as a result of the low site elevation relative to Lake Ontario, and as required to accommodate on-site ponding to achieve SWM objectives.
The site storm servicing was integral to the SWM design as it provided opportunities for the underground storage of stormwater during major storm events. The storm servicing design also incorporated on-site infiltration beds designed to infiltration clean roof drainage into the ground as required to achieve water balance objectives, and a combination of bio-treatment areas and a package water treatment unit to achieve City of Toronto, and LEED, water quality objectives. Given the close proximity to the groundwater (< 2.0 metres from the surface), the bio-treatment area design incorporated an impermeable liner which prevented contaminants from being transported directly to the groundwater system.