Town of Arnprior Water Pollution Control Plant Class Environmental Assessment
- Project Management
- Location: Arnprior, Ontario
- JLR Contact: Mike Duivenvoorden
- Related Projects: Trenton WWTP Class EA, Cornwall WWTP Class EA Amendment, Ravensview WWTP Class EA Amendment, Kirkland Lake WWTP Class EA, Callander Communal Sewage System Class EA, Lively Walden Wastewater System Class EA
JLR designed the town’s original primary treatment plant in the 1960s. In later years, the plant was expanded and secondary treatment was added. As the Town of Arnprior continued to grow, capacity and other issues at the plant required attention. JLR carried out an update to the Class EA to identify and address these needs. The public consultation process with the MOE, MNR, and OPG was supplemented by a Project Liaison Committee including senior town Management and Operations Staff, Council representation, and the MOE.
Notwithstanding complex geotechnical conditions, the EA analysis concluded that an expanded plant on the current site offered superior cost benefits over a new plant on a new site. The site’s geotechnical challenges, including karstic features and limited bearing capacities, steep bedrock, and significant dewatering requirements dictated customized solutions for each new plant component location. Other constraints requiring innovative solutions included a confined site, no buffer zone to neighbouring residential areas, a prominent location within the community, and several species at risk.
The level of detail included in Phase 3 of the Class EA allowed the project to be considered “shovel ready” for funding initiatives. The ESR’s recommendations included expansion for a build-out population of 11,000, nitrification, upgraded screening, elimination of hydraulic bottlenecks, reduction of primary bypassing, capturing most wet weather flows (up to 59,000 m3/day), secondary bypass flow, a central odour control system, disinfection upgrades, anaerobic digestion, and extension of the outfall sewer to the Ottawa River.
JLR subsequently prepared the detailed design and contract documents for a multi-million dollar construction contract for all of these upgrades. The project has now been successfully implemented and will provide Arnprior with safe and reliable wastewater treatment for many years to come.