The Brief

Considering the broader environment is the first step to truly effective engineering designs. We worked with the Regional Municipality of Halton to create a watermain solution that would transform water supply while respecting the land around it.

Project Overview

Nurture nature to fuel innovative design

Environmental considerations must figure prominently at the heart of infrastructure design. When the Regional Municipality of Halton set out to increase water supply to its growing neighbourhoods, our team committed to designing with the broader environment in mind.

This area is criss-crossed by a rich network of creeks and escarpments. It’s also home to the Bronte Creek Provincial Park. For us, the engagement wasn’t simply about securing the water supply for North Oakville and Milton. It had to mean doing so in harmony with the unique nature of the land itself.

Geotechnical field investigations were integral to our design process. A large-diameter watermain connecting the Burloak Water Purification Plant with the Kitchen Reservoir would get the job done. The challenge, though, was to create a design that didn’t disturb environmentally sensitive areas, the at-risk species that live there, or existing rail, highway, and hydro facilities. From the earliest days of this consulting engineering services engagement, the geotechnical insight we uncovered became our guide and single source of truth. With that insight in hand, we landed on a tunnelled watermain solution as the best possible route forward.

How did we bridge the unique geotechnical findings with innovative design features? The 6.7 km long tunnelled watermain was conceived with only four shaft sites. This allowed general contractors to minimize impacts on the highly sensitive Bronte Creek , as well as several other at-grade features they would need to cross. By creating a permanent shaft and service building to house the watermain as it rose to grade, our design allowed most of the construction to take place without disturbing local residents.

This award-winning design also included what was then a region first: zero-leakage pressure testing. This is the most challenging test of its kind in the industry. This future-forward assessment saw the watermain hold a pressure of 150 psi for three hours straight—with zero leakage. At points plunging 60 m deep, the tunnelled watermain was built to perform efficiently, while integrating naturally into the surrounding environment.

Fast-forward to now, and Halton can rest assured: we’ve prepared the region for future growth, all while respecting nature, and the environmental features, that make this part of Ontario so very special.