GHD and the Regional Municipality of York receive OPWA award for technical innovation

The Ontario Public Works Association (OPWA) awarded GHD and the Regional Municipality of York (York Region) the 2017 Technical Innovation Award at its annual conference and award luncheon in January, 2018. This award recognizes the development, management, and implementation of a creative idea, device, process, or system that enhances the goals of public works in serving the public and protecting the environment.

The new 84-million-litre-per-day (MLD) pumping station is one of the largest in the Region, and the re-chloramination facility is part of a unique and expanding network of similar facilities in the area. These facilities enable the Region to distribute treated water from Lake Ontario, 50 kilometres north, to the Towns of Newmarket and East Gwillimbury, while maintaining excellent water quality.

Several advanced and unusual design features and construction techniques were used to ensure success during construction, mitigate environmental impacts on sensitive habitats, and minimize disruption to the public. These features included the use of sophisticated caisson shoring systems to reduce groundwater discharges, tunnelling using earth pressure balance methods, and the installation a 1,050-millimetre pipeline under an existing reservoir.

The new re-chloramination facility was designed to provide robust water quality monitoring, manage nitrification risk, and control secondary disinfection residuals in the existing South Richmond Hill reservoir. A key feature was the inclusion of a sophisticated control scheme that adjusts chlorine and ammonia as required, boosting the disinfection residual while binding up free ammonia as monochloramines.

Enhanced water quality provided by the new re-chloramination facility will ensure the continued provision of safe, reliable drinking water in the Region for many years.