The City of London retained Dillon to design plant upgrades for the Vauxhall Pollution Control Plant (PCP), which treats municipal wastewater. As a result of the combined sewer system, the Vauxhall PCP experienced periodic combined sewer overflow (CSO) by-pass events during wet weather conditions, where flows to the plant could exceed 100 000 m3/d.
Dillon’s preliminary work identified a preferred solution for handling wet weather flows at the Vauxhall PCP to meet Ministry of the Environment (MOE) Procedure F-5-5. The preferred solution was a chemically enhanced primary treatment (CEPT), in combination with upgrade or replacement of the inlet works, chemically enhanced secondary clarification and in-plant flow diversion. This solution can accommodate total flows up to 200 000 m3/d.
Dillon completed the detailed design of all the outlined plant upgrades, obtained permits and approvals and provided construction administration services, which included ongoing support and site services during commissioning and start-up.
The $5.6M PCP upgrades included:
- Inlet works designed to handle peak flows including:
- Fine step screens in oversized inlet channels
- Vortex grit removal system
- Ozonation for odour control
- Flow control weir gates to allow for staged flow control and diversion within the plant
- Iron salt and anionic polymer chemical systems for CEPT
- Iron salt and cationic polymer chemical systems for chemically enhanced secondary clarification
- Waste and return activated sludge pumps.
Dillon was recognized by the Consulting Engineers of Ontario with a 2014 Award of Merit in the Environment category. Click here to view the award video.