Penticton Creek is an urban waterway running through the City of Penticton, BC that historically supported native fish species including Rainbow Trout, and Kokanee and Sockeye Salmon. After flooding in the 1950s that devastated the downtown, the creek was channelized and lined with concrete. While the channels serve its purpose for flood control, the concrete works negatively impacted the fish habitat in the creek.

A City initiative to prioritize the downtown core recognized Penticton Creek as a significant natural and cultural resource. Overwhelming support for its revitalization led to a master plan to restore the creek in several phases over many years. In 2018 City Council approved the plan.

Between 2019 and 2023, work was undertaken to restore a 320-metre section of the creek known as Reach 3A Upper and 3B to create a high-quality fish habitat while maintaining flood protection. Prior to the works, the concrete lining of the 7-metre-wide channel with an average slope steepness of 2.1% was showing its age and the aquatic habitat in this reach was of low quality with limited areas for spawning and numerous fish passage barriers.

The restoration involved the demolition and removal of the concrete lining, removal of a bridge, and re-grading to create a rehabilitated riffle-pool channel with 10 riffles and 11 pools. Riprap and boulders were placed at the side slopes and bottom of the channel and spawning gravel added. The riprap and boulders provide robust and resilient erosion protection. Together with the gravel and riffle-pools, a natural water course with a mix of fast shallow and slow deep flows and meandering runs that provide important areas for fish food production, spawning and migration was created.

Native trees and other vegetation were also planted along the creek banks to restore the waterway to its natural habitat. Days after in-creek work was completed, fish were observed utilizing the newly constructed spawning pools.

Knowing that Penticton Creek is a core part of the City’s safety infrastructure while also an important natural and cultural amenity, our team approached the project mindful of the diverse needs of the Penticton Creek Restoration Committee. The Committee included City staff, provincial ministries, and members of the Okanagan Nation Alliance, Penticton Indian Band, local fly-fishing community, downtown business improvement association, and general community residents who live near the project.

The project team completed an analysis that included the use of 1- and 2-dimensional modeling, application of natural channel design principles, bio-engineering strategies, optimum spawning gravel distribution for fish habitat and flood resiliency, incorporation of climate change impacts on peak flows, and consideration of groundwater impacts to the proposed works. An environmental assessment characterized and mapped existing vegetation, wildlife and wildlife habitat, fish and fish habitat, defined regulatory permits and approvals required, and recommended mitigation measures and controls for potential project related environmental impacts in both the design and construction phases.

Throughout the project, extensive engagement and consultation with the Committee provided a forum to share ideas, explore options, and receive feedback. This alliance approach was integral to the delivery of a good design to restore Penticton Creek to meet the distinct needs of the Committee members.

Restoration of this reach was completed December 2023. It led to a 270% increase in pool habitat within the reach, 0.6-metre-deep pools capable of preventing loss of spawning gravel up to and including a 2-yr flood event, riparian vegetation for additional fish habitat and cover, and resiliency for a 200-yr instantaneous flood event (including climate change). The naturalized creek provides increased fish habitat, an attractive space for the community, and supports vital ecosystem functions.