About the Project
Like many major urban streams, Bowker Creek in the District of Saanich is partially contained within pipes and culverts with numerous open stream stretches confined within banks to accommodate residential and commercial development. At Richmond Road the in-growth of invasive species trees and root systems resulted in a redirection of flows against steep banks downstream of a large, long culvert. The erosion and undermining nearest the culvert discharge threatened the only access to a parking lot for a large multi-storey apartment building and, if unabated, possibly the building itself.
The project involved a review of both hardscape and softscape options, detailed design of the preferred solution and oversight of Saanich forces during construction. Typical textbook approaches would not fit with the constrained footprint of the site. The recommended approach, using sound engineering principles, was a hybrid solution with vegetated geo-modular wall system combined with a rip-rap energy dissipation apron and toe protection to optimize stream hydraulics, protect against high 20-year design flow velocities and assist long term stabilizing vegetative growth.
Implementation by Saanich staff and a team approach to construction provided the highest level of quality control and adaptability to resolving site issues. Public outreach by Saanich and an appearance suiting the urban greenway ensured positive public acceptance and support.
Following removal of invasive species new native trees and shrubs were planted to provide protective canopy for the stream as they mature.