Mid-Halton WWTP – Oakville

The Mid-Halton WWTP Project was a significant expansion to an existing treatment plant located in the Town of Oakville which services portions of the Town of Oakville, Town of Milton, Halton Hills and City of Burlington. The planned Phase IV and V expansion added 50 Megalitres/day (ML/day), increasing the plant rated capacity from 75 Megalitres/day to 125 Megaliters/day. Phase IV and V expansions to the Wastewater Treatment Plant includes work in each the following areas:

• North Pumping Station – Increasing the firm capacity from 100 MLD to 318 MLD. Work included the construction of a new wet well and corresponding dry well to house the installation of four new dry pit submersible pumps. Part of this expansion includes the installations of both a new forcemain to support larger flows and a new bypass pipe rerouting flows to a new UV disinfection facility.
• Influent Flow Splitting – Construction of new Influent Flow Distribution Chamber to receive all (125 MLD) raw sewage from the North and Third Line Pumping Stations and to direct 75 MLD to the existing Headworks and 50 MLD to the expanded facilities.
• Preliminary Treatment – Includes new headworks building, two new mechanically cleaned bar screens and two bypass channels, two new Vortex grit units/ conveyors/ dewatering equipment, and odour control facilities, as well as installation of four new primary clarifiers to accommodate additional wastewater flows.
• Secondary Treatment – Expansion of the secondary treatment process with a conventional activated sludge system including two new aeration tanks and four new secondary clarifiers.
• Phosphorus Removal – Expansion of the existing ferric chloride chemical addition system to accommodate the additional flow.