Tetra Tech Canada has won an award of merit in the natural resource and habitat category in the 2026 Association of Consulting Engineering Companies British Columbia (ACEC-BC) awards for engineering excellence.
The company won for quickly stabilizing the banks of a creek in residential North Vancouver whose banks had eroded due to flooding and were in danger of damaging the foundation of buildings in the area.
“We are truly honoured and proud of this achievement,” says David Moschini, Tetra Tech Canada’s manager – water resources and infrastructure.
Following the October 2024 atmospheric river that dumped days of heavy rain on southwestern B.C., Thain Creek suffered a major slope failure.
The slope eroded until the bank of the creek was within six metres of the foundation of the nearby Cypress Gardens condo complex, creating an immediate public safety hazard.
The slope failure caused severe channel erosion, which led to significant amounts of water flow going underneath the earth and rocks of the surface of the channel, which meant there wasn’t enough water for the fish to swim in.
To help stabilize the banks of Thain Creek and to restore the local ecology, Tetra Tech provided hydrotechnical, geotechnical and environmental engineering services.
Because the situation was so urgent, the design, tendering, permitting and construction were accelerated and completed in only 10 months.
Moschini says the quick completion of the project was made possible by the collaboration of Tetra Tech’s environmental team and the City of North Vancouver.
“We are also grateful for the support and collaboration from the regulatory agencies and the District of North Vancouver, which worked closely with us to meet the demands of the project’s accelerated schedule,” he says.
Moschini says Tetra Tech took an innovative approach to the Thain Creek challenge.
Rather than concentrating all of its efforts by addressing the erosion on only one side of the channel, Tetra Tech raised the entire ravine – both sides and the creek bed.
“The creek bed was raised by up to four metres, which enabled the construction of a stepped series of pools and riffles to restore fish passage and improve habitat quality,” says Moschini. “It provides long term stability along both sides of the creek.”
A vegetated revetment system (to prevent erosion) combining riprap armouring (loose stones to protect creek banks) and riparian planting (natural vegetation to prevent creek bank erosion) was installed to stabilize slopes and re-establish shading and bank structure.
Large woody debris and boulder clusters were installed to increase channel complexity and support aquatic habitat diversity.
To ensure channel stability and to prevent subsurface seepage, Tetra Tech installed non-woven geotextiles (highly permeable synthetic materials), bentonite and fine sands and gravels.
The completed project improved the long-term slope stability of the entire ravine, removed barriers to swimming fish, reduced the risk of erosion, and enhanced habitat connectivity.
“Thanks to integrated engineering and environmental planning – carried out on an emergency timeline – the project restored ecological function and also addressed critical public safety concerns,” says Moschini. “The solution is permanent. There aren’t going be any more problems with the banks of Thain Creek.”
Moschini says “doing the project on an accelerated timeline proved to be a prudent decision.
“During the recent fall and winter seasons, we experienced several intense storm events that could have led to slope failures, had stabilization measures not been implemented.”
Moschini says there isn’t a one-size-fits-all approach to dealing with creek erosion.
“Every creek restoration project is unique, with its own set of site-specific challenges, including channel geometry, surrounding infrastructure, hydrology, sediment conditions, and ecological requirements,” he says. “Because events such as atmospheric rivers can impact each system differently, effective solutions must be tailored to the specific conditions and risks at each site.”
There are, however, some measures that could be standardized as well as ways municipalities can prepare in advance for situations like the Thain Creek emergency.
“For example, municipalities could pre-qualify contractors ahead of time so that, in the event of a storm, they can engage qualified companies without needing to complete procurement processes under emergency conditions,” says Moschini.
“This step could be done proactively before a storm event occurs.”
In addition, municipalities can be proactive and assess the condition of existing infrastructure and prioritize upgrades to facilities that aren’t designed to handle the large storms that can be caused by climate change.
Tetra Tech received its award at the ACEC-BC 2026 Awards for Excellence Gala, which took place May 8 at the Vancouver Playhouse. Some 420 people attended the event.
This year marked a milestone for ACEC-BC, as it celebrated its 50th anniversary.
