Comox Valley Water Treatment Plant

The Comox Valley Water Treatment Plant was completed in October 2022, marking the largest infrastructure initiative undertaken by the Comox Valley Regional District (CVRD) to date. The new system provides a vital source of clean drinking water for the communities of Courtenay, Comox and K'ómoks First Nation in British Columbia.

Stantec, as prime consultant to Aecon’s design-build team, worked with CVRD and the community to deliver a new water treatment plant and conveyance system, which supplies 75 million L per day (MLD) of treated water from Comox Lake. The firm also worked with the K'ómoks First Nation (KFN) community to design the facility, which resides on KFN territory.

CVRD provides water to 50,000 residents. Since 2014, the unfiltered system had suffered through boilwater advisories relating to turbidity issues. To resolve concerns from the public and the provincial ministry of health, including meeting surface water treatment guidelines, CVRD planned for the design and construction of new facilities.

Built with future regional growth in mind, the new system provides flexibility to address raw water quality variations caused by climate change. Comox Valley communities now have access to a secure supply of reliable, high-quality drinking water for generations to come.

Multiple improvements

Improvements were made to components of the water treatment sy stem with a multi-barrier approach from source to tap, which involved source protection, monitoring, reducing turbidity and removing the risk of viruses and bacteria, with three levels of tr eatment—filtration, ultraviolet (UV) and chlorination. This included a new lake intake (to access cooler water), lakeshore raw water pump station and transmission main, direct filtration water treatment plant and treated water transmission main.

To preserve the beauty of the surrounding area and mitigate noise concerns for residents, an underground pump station was built at Comox Lake. An intake tunnel was constructed to reduce impacts to the lakebed and fisheries. Energy conservation features were incorporated, including natural and LED lighting, energy-efficient residuals dewatering and high-rate filters to reduce the footprint needed for the facility. All process water is recycled, including spent filter backwash water, enabling 99% of water coming into the plant to be processed with minimal wastage.

The new treatment facilities were delivered in 30 months from design to completion of construction, through the COVID-19 pandemic disruptions and hyper-inflation.

An accelerated schedule

The key challenge with this $126-million project was the accelerated schedule to meet deadlines set by key stakeholders. When the province declared a state of emergency due to the pandemic, it presented restrictions that affected pr oject completion, heavily impacting the labour force and the supply chain for major equipment and materials.

Deep collaboration and support from CVRD made the 30-month schedule achievable. The Stantec/ Aecon integrated design-build team also worked closely with operations and maintenance (O&M) staff, KFN, BC Hydro and Island Health.

The design was completed six months after the notice to proceed through four formal stage gate reviews at 30%, 60%, 90% and 100% of design. Early work packages and major equipment procurement were issued concurrent with the design package to facilitate the start of construction. Stantec’s multidisciplinary team fasttracked design management, scheduling and risk and cost management.

Showcasing local talent

In addition to clean drinking water, the project provides access to community facilities, ar t, trails with potable water taps and lake water supply for a new hatchery project.

The project was 100% designed by local technical experts and employed a workforce almost entirely (99%) local to Vancouver Island. Employment opportunity goals for First Nations people, apprentices and underrepresented people were far exceeded, in most cases doubling, tripling or quadr upling the targeted hours.

Environmental integration

The architectural design incorporates a glue-laminated (glulam) wood roof structure and beams in the operations building. The result is an esthetically pleasing facility that integrates with the natural environment.

The site incorporates landscaping, porous pavers to control runoff. Water from the plant is supplied to a local trailhead interpretive centre for public use.

L ow-carbon concrete was used to reduce the project’s environmental impact. Natural light with light tubes and LEDs r educes the need for electricity. Energy efficiency was also emphasized in the selection of process equipment, including the low-energy pr ess dewatering system, which reduced energy needs by 96% in comparison to other dewatering options, such as centrifuges.

All process water is recycled from the treatment system. The process design was also optimized to reduce the need for chemicals for water coagu- lation. Heat recovery was incorporated into the HVAC systems, to reduce both operating costs and emissions.

Comox Valley Water Treatment

Plant, Courtenay, B.C.

Award-winning firm (prime consultant): Stantec, Burnaby, B.C. (Reno Fiorante, P.Eng., P.E.; Miles Yi, Ph.D. P.Eng.; Tony Brcic, P.Eng.; Shaun Gill, P.Eng.; Steven Cho, P.Eng.; David Harding, Architect AIBC, OAA; John Netzel, P.Eng.; David Law, P.Eng.; Al Ghanam, P.Eng.; Shaun Swarbrick, P. Eng.).

Owner: Comox Valley Regional District (CVRD).

Other key players: Aecon Water Infrastructure (client), Anthratech Western (filter underdrain system), Trojan Technologies (UV disinfection system), FKC (screw press dewatering system).