The upgrades at the Strathmore Wastewater Treatment Plant were completed under a design/build contract, including team members from the Town of Strathmore, Epcor Water, Maple Reinders, AECOM Canada, and J.R Huggetco. Maple was contracted to increase the capacity of the existing wastewater treatment plant as well as convert the entire treatment process to a conventional continuous flow BNR configuration, and effectively retrofit the two existing SBR reactors into BNR reactors.
The scope of work included a new 4,000 square foot solids and sludge handling building, consisting of influent flow metering, fine screens and screenings compaction, vortex grit removal and classification, dissolved air floatation thickening, polymer injection systems, centrifuge and sludge conveyance, indoor grit/screenings/sludge containers, new main electrical room, and housing the majority of process pumping units and piping systems.
Outside the solids building new construction and equipment included 410 meters of 900 mm diameter reinforced concrete pipe influent sewer and collection box structure, raw sewage lift station and dual pumping units, and 35m diameter Combined Treatment Unit (CTU) consisting of a central primary clarifier/fermenter surrounded by a BNR reactor. Further, two 21m diameter secondary clarifier units, return activated sludge (RAS) tanks and pumping units, flow splitting concrete structures and a tertiary treatment structure housing cloth media filtration, UV disinfection, and effluent reuse and chlorination water systems were constructed. An elaborate underground piping network provided flow direction between all structures.
Upon completion of the above construction, the new facility was brought online. Within a single week timeframe, influent flows were redirected to the new works in 3 equal increments. Treatment quality of the sewage was immediately within specifications. Once stabilized, the existing 2 sequential batch reactors (SBR’s) were decommissioned by operations, and Maple Reinders proceeded to retrofit these concrete tanks to provide an additional 14ML of BNR reactor treatment capacity.
Aside from the treatment process, Maple Reinders undertook the decommissioning of the existing screenings and solids systems, removing them entirely and converting the space to a workshop/storage area. Concurrently, the existing administration facilities were renovated and the laboratory was completely reconstructed to provide modern analysis and testing capabilities to match this state of the art treatment process.
With the new facility, treatment capacity of the Town of Strathmore’s wastewater infrastructure was increased from 6ML/day to 20ML/day, allowing for 25 year growth from a population of currently 12,000 to 30,000 citizens. Further expansion and growth potential is afforded by the modular design of the facility.