Telling the tunnel story
Watch the documentary to learn more about how FortisBC progressed the tunnelling solution beneath the Skwelwil'em Squamish Estuary to address concerns raised by Sḵwx̱wú7mesh Úxwumixw. It highlights how shared values – respect for the environment, Indigenous rights, and culture shaped one of the project’s most important decisions.
Protecting what matters
For Sḵwx̱wú7mesh Úxwumixw, the Skwelwil’em Squamish Estuary is more than a stretch of land and water — it’s a living part of their culture. When the EGP Project was first proposed, Sḵwx̱wú7mesh Úxwumixw expressed the importance of protecting the estuary.
The Skwelwil’em Squamish Estuary plays a vital ecological role serving as a habitat for sensitive plants, fish and wildlife. As a condition of regulatory approvals from the BC Environmental Assessment Office (EAO) and Sḵwx̱wú7mesh Úxwumixw, the project must utilize an underground trenchless construction method and avoid industrial impacts to the 673-hectare area. Sḵwx̱wú7mesh Úxwumixw is not just an interest holder on the project – they are also a regulator, with the authority to set and enforce its own independent set of conditions.
“It’s really important that we maintain two-way dialogue with the Nation to ensure that Squamish Nation conditions are being met, and that the Nation’s interests are being heard,” shares EGP Indigenous Relationship Manager Agatha Ho.
Engineering with respect
Recognizing the importance of the estuary, FortisBC engaged directly with Sḵwx̱wú7mesh Úxwumixw to determine a solution to protect it. Instead of building a more conventional overland route, FortisBC developed an innovative solution: tunnelling beneath the Skwelwil’em Squamish Estuary using two specialized tunnel boring machines. This approach avoids surface impacts to the estuary and helps preserve its integrity, while still allowing the project to move forward.
“Now we’re integrating an Indigenous perspective and an industry perspective in regards to how we do this to make sure it’s done right,” explains Wilson.
While most tunnelling projects focus on transportation or water systems, this one is unique: the tunnel boring machines were designed specifically to carry a natural gas pipeline, while avoiding any surface impacts to the Skwelwil’em Squamish Estuary.
“Very rarely do you actually build tunnels for natural gas pipelines. Further complicating [the project] is that you’re going through two distinctive subsurface conditions, which really drives the need for two tunnel boring machines that would work towards each other, which again, is unusual,” noted FortisBC Project Director Darrin Marshall.
A tailor-made design
The nine-kilometre tunnel will extend from the Woodfibre LNG site to the BC Rail site in Squamish, passing under Monmouth Mountain and approximately 25 metres below the Skwelwil'em Squamish Estuary.
The ground conditions are dramatically different along the tunnel route with hard rock under Monmouth Mountain and soft ground beneath the estuary. These conditions required entirely different engineering solutions. Each tunnel boring machine was custom-built for its section of the tunnel, with specific designs for excavation, support, and stability. Crews spent approximately eight weeks assembling each tunnel boring machine and preparing for the full-scale tunnelling operation.
“This is a tailor-made design. This is a machine designed for this specific project,” said Tunnel Senior Project Manager Ignacio Calvo González.
A meaningful path forward
This tunnel isn’t just an engineering achievement – it shows what’s possible when engagement, collaboration, and shared values guide complex decisions. The ongoing dialogue between FortisBC and Sḵwx̱wú7mesh Úxwumixw is building more than a tunnel; it’s helping build trust, mutual understanding and a collaborative way of working together.
