Westbrooke Stormwater Detention Centre Offers Innovative Solution

Langley, BC — Located in Langley’s Willoughby Heights neighbourhood, Westbrooke is a Qualico Community that features one of the largest underground stormwater detention facilities in North America. The sustainable and innovative facility is the first-of-its-kind in the Township of Langley, servicing a 127-acre catchment area.

The facility was a requirement for development approval for Westbrooke I, as the Township of Langley establishes development prerequisites in its neighbourhood plans that must be secured before any development application will go through. One of those prerequisites was to secure the land and construct the stormwater management facility that would service the whole catchment area.

Aerial view of the stormwater detention facility's development

However, the availability of land for a detention pond of this size was limited and the acquisition expensive. The Township of Langley, Qualico, and McElhanney Consulting Engineering Ltd. collaborated on a solution, with sustainability and cost efficiency in mind. It was proposed to combine two municipal facilities into the same footprint: a stormwater detention tank system installed below the sports fields in Yorkson Community Park.

Liz Collins, Senior Development Manager, Qualico Communities BC, said the collaboration between the three parties worked well.

“The Township of Langley had recently secured an additional 20 acres to expand the Yorkson Community Park – an excellent location for our underground storm system,” she said. “The Township was agreeable to the underground storm system, provided we include a community amenity of some kind. The perfect solution was for Qualico to construct the soccer fields that the Township envisaged for the park above the stormwater detention system, resulting in the Dual Use Detention Pond/Sports Field.”

The 21,200-m3-system includes storm sewers, detention tanks, and flow diversion manholes to redirect sediment and debris during heavy rainfall, as well as two natural grass turf fields at surface-level.

McElhanney drew on experience in stormwa­ter detention to develop a non-traditional and innovative solution to achieve the same benefits of conventional stormwater detention, with substantial cost savings for both Qualico and the Township.

The stormwater detention facility's development

Overall, the innovative design resulted in $6 million in land cost savings for Qualico, and the construction of the soccer fields provided a $1 million community benefit for the Township of Langley. As well, in 2019, the Association of Consulting Engineering Companies of BC (ACEC-BC) awarded McElhanney Consulting Engineers the Award of Excellence for the Dual Use Detention Centre/Sports Field.

Liz said Communities BC can face challenges to purchase and develop land such as finding contiguous land parcels for assembly, dealing with the high price of land versus low densities and environmental restrictions. She noted that the Westbrooke challenges provided the team with some valuable insight into approaching future projects.

“Perhaps what was learned, or was reinforced,” she said, “was not to shy away from considering new ideas. An underground storm system was a new learning curve. We were able to get the busy water resources management and parks department teams at the Township excited about this project. Only the City of Abbotsford had an underground storm facility previously. This one was much bigger, one of the largest in North America, and the Township would be one of the leaders in the sustainable use of land and innovation.”

View the showcase project on this website here.