The Brief

Working closely with Durham Region over a 12-year lifecycle, RVA delivered a cost-effective solution to extend the service life of one of its largest wastewater treatment facilities by 15 to 20 years.

Project Overview

Building liveable communities for the long-term

Nestled between lakes Ontario, Simcoe, and Scugog lies Durham Region. The appeal of its diverse landscape has made it one of the fastest growing municipalities in Canada, with a population base that is projected to grow to 1.3 residents million by 2051. However, its booming growth also means added pressure on the Region’s 11 wastewater treatment facilities, and ensuring the long-term viability of its existing infrastructure has become imperative to sustaining Durham Region as a thriving community now and in the future.

One of the Region’s larger facilities, the Harmony Creek Water Pollution Control Plant (WPCP), is an activated sludge treatment facility with a rated capacity of 68,100 m3/d that services the communities of Courtice and Oshawa. As the current site was insufficient to accommodate the planned growth in the area, the Region looked to RVA to complete the detailed design and construction administration for major maintenance works and upgrades at the Harmony Creek over three phases from 2009 and 2021. The major components of the maintenance program included: upgrades of primary treatment system, replacement of primary and secondary clarifier mechanisms, upgrades of blowers and aeration system, addition of new disinfection facility, and upgrades to the solids handling and thickening systems. The work also included the construction of a new administrative building and a plant-wide SCADA network.

Delivering innovation at speed

Harmony Creek’s maintenance program was approved under the Government of Canada’s Clean Water and Wastewater Fund, which placed stringent deadlines on the overall project. As the existing plant had to remain operational during construction, our team developed a project management plan in line with PMI’s PMBOK® standards. To minimize impacts on the local community and plant operators, our team implemented precise constructability measures throughout the project lifecycle to keep systems online during major upgrades:

  • Phase 1 (2009 – 2013):  We took proactive steps to pre-purchase several major pieces of equipment with long delivery timelines. An alternate power supply configuration was also developed to power critical plant loads, which avoided provision of a temporary standby generator.
  • Phase 2 (2013 – 2016): RVA developed a unique methodology for replacing the facility’s blower building MCC to reduce downtime and allow the plant to operate with minimal process disruption.
  • Phase 3 (2016 – 2020): A detailed plan and procedure for blower piping modifications was developed to facilitate blower replacement. In addition, a detailed step-by-step plan was developed to commission various upgraded components of the plant. Phase 3 was completed in just five months to meet the funding deadline.

Designing for facility and site renewal

The existing administration building at Harmony Creek was originally constructed in 1952 and no longer met the needs of plant operators. Through our stakeholder engagement process, our team identified areas for improvement and designed a new single-storey 385m2 administration building that would support the broadest range of potential users. The administration building was constructed to be fully accessible as a staging area for visitors to the site and for potential tours. The building was also outfitted with new staff amenities for operating staff, such as new restroom facilities, locker rooms, meeting rooms, a lunch room, and a laboratory. In addition, we designed three new offices for plant management and SCADA personnel, who are now able to access SCADA servers in a dedicated room in the new building.

In addition, several environmental protection plans had to be considered during construction, one of which was necessitated by the presence of impacted soil in the proposed location for the disinfection system. Our team made a collaborative decision with the Region to have the impacted soils stored onsite and repurposed as a berm to prevent negative impacts to the environment. Other onsite measures included the installation of a heavy-duty silt fence barrier, straw bale barrier, and an excavated sediment trap.

Driving operational efficiencies

Known as the “Clean Energy Capital of Canada,” Durham Region maintains a proud reputation as a leader in industry transformation and energy innovation. Similarly, we wanted to maximize the service potential of Harmony Creek across the full spectrum of its operations by developing a number of innovative, yet practical solutions for Harmony Creek that would deliver significant savings in cost and time. We replaced existing centrifugal blowers with high efficiency turbo blowers, which utilize less power to supply the given volume of air for biological treatment. We also converted the coarse bubble aeration system to fine bubble aeration to help the facility realize significant savings operating costs. Finally, our team developed a new gravity sludge thickening system to aid with polymer dosing at the plant, an addition that reduced costs and time during construction and is expected to yield approximately $340,000 in savings related to biosolids haulage every year.

Smart growth requires complex planning to realize a long-term vision. The careful phasing this project, as well as our close collaboration with Durham Region stakeholders – from weekly health and safety consultations to daily site inspections – led to the extension of Harmony Creek’s service life by another 15 to 20 years. The new-and-improved plant is a key component of Durham Region’s modern infrastructure that upholds the reputation of its home city for leading the way in technology and innovation. More than just a plant upgrade, the culmination of our team’s efforts is a technical achievement that will safeguard the health and well-being of Durham residents, improve long-term water quality, preserve local ecosystems, and lay the foundation for new growth across the region for future generations.