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The Sam Livingston Fish Hatchery is Canada’s largest indoor trout hatchery, producing approximately three million trout for release each year into publicly accessible water bodies throughout the province of Alberta. The hatchery wastewater contains elevated levels of nitrogen and phosphorus and must be treated before release into the Bow River.
Earth Tech was retained by Alberta Environment to provide complete engineering and construction services for the interpretive wetlands and biofilter backwash waste treatment system to treat the hatchery effluent.
The concept for the Pearce Estates Park Interpretive Wetland included a subsurface flow treatment wetland, a backwater pond, sandstone pool, floating bog, marsh and backwash water pumping system. Hydraulics proved a major challenge for the project, with cells at different levels and often sloping in the opposite direction of the required flow. A series of standpipes weirs were designed to control the hydraulic grade line for these cells. Pumps were carefully selected to handle the flows and to provide the required head to effective transfer the wastewater.
The Pearce Estate Interpretive Wetland project not only provides natural treatment of hatchery wastewater, including removal of approximately 84% of the total phosphorus, but also serves as a unique educational facility, providing information about aquatic ecosystems to park and hatchery visitors.
