As the oldest city in Canada, founded in 1785, Saint John is rich with Victorian architecture, unique landmarks and historical treasures, like the City Market. But not all of Saint John’s history is on the surface. Buried beneath the streets of this storied city lies an important piece of the past: a water pipeline that is more than a century old.

Developed in 1837, Saint John’s water system is the lifeblood of the community, delivering running water to nearly 70,000 homes and hundreds of businesses. With some of the city’s most critical piping dating to 1874, aging infrastructure has led to frequent watermain breaks, disrupting and contaminating Saint John’s water supply.

Poor water quality further challenged the availability of clean water in the community. Unfiltered surface water from the city’s system contained significant amounts of disinfection by-products at levels that often exceeded those prescribed by current standards, posing a potential risk to public health. As a result, Saint John has routinely imposed boil water orders, requiring residents to use bottled or boiled water for drinking, and to prepare and cook food.

With a vision to improve the community’s most critical infrastructure, deliver safer drinking water, and reduce water disruptions for residents, the city embarked on a quest to develop a new drinking water treatment facility and storage reservoirs. Saint John used a public-private partnership model to develop the single largest municipal infrastructure project undertaken in New Brunswick’s history, and they selected us to partner with them as lead designer.

Powered by our passion to build more resilient water infrastructure that meets current and future demands, we pursued sustainable and affordable solutions to design:  a new 75,000-cubic-meter per day surface water treatment plant; 33,000 cubic meters of new storage reservoirs; and, a 18,000-cubic-meter per day groundwater wellfield.

To further overhaul crucial aging assets, our team designed improvements to the water transmission system, several pumping stations and 16 km of water pipes that were replaced.

A critical part of the design included ensuring the facility had minimal impact on the environment. The water treatment process uses chemicals which can pose environmental risks. Chemical containment is required in the event of accidental spills during chemical delivery. So, we pioneered the design of a chemical containment area and associated drain collection structure with a unique three-way valve system to ensure the containment of any chemical spill during bulk chemical offloading.

Our team also eliminated the use of settling ponds for the storage and dewater of solids removed from the treatment process. This protected five hectares of trees on the property and provided an essential buffer between the facility and the nearby Little River Reservoir. This helped minimise the environmental footprint of the plant’s operations.

Meeting both Canadian and New Brunswick water quality standards, the Loch Lomond Drinking Water Treatment Facility officially opened in 2019. In the first few months following commissioning, the facility removed 15 tonnes of organic matter from Saint John’s drinking water. The removal of solid material improves the health of the entire water system and ensures a reliable supply of clean, safe water is delivered not only to the current community today, but also the generations to come.

Note: This work was initiated under Wood’s E&I, who joined WSP in an acquisition completed in 2022.