Fighting fire with forest: Saint John plants trees to safeguard drinking water supply

CBC

14-06-2025

As wildfire risk grows with hotter, drier summers, Saint John is turning to trees to provide frontline protection for its drinking water — by cutting down trees in high-risk areas and planting more resilient native species.
The goal is to prevent the spread of wildfires in the Loch Lomond watershed, said Dean Price, manager of source water protection for the City of Saint John.
"It's more than just the water, we want to have a healthy forest that surrounds those lakes," Price said.
The watershed supplies clean water for most Saint John residents and businesses.
Some areas around the Loch Lomond water supply are at a higher risk of wildfires during the often dry and scorching summer months. As a proactive measure, the city has been planting more trees in high-risk areas to protect the water supply from possible contamination.
After a wildfire, the debris from burned trees and erosion caused by the damage contaminates the water and makes it harder to treat.
"We're doing restorative forestry," Price said. "So we're actually cutting down trees in high-risk areas, and then we're going to be replanting with a better mix of trees."
The trees they are cutting away are dry and more susceptible to fire.
Price said that the goal is to replace the old trees, primarily balsam firs, with a variety of other species, such as oak, red spruce and maple.
"Ideally, you want to have a forest that's a mixture of hardwoods and softwoods. It's more resilient, better for biodiversity and also for the overall health of the forest."
Price said his department has been working with ACAP Saint John to plant the new trees in the Loch Lomond area.
Roxanne MacKinnon, ACAP's executive director, said the species of trees being planted are all native to the area, which means their survival rates will be better.
"We've been doing water-quality monitoring," MacKinnon said, "to also get a sense of what the water quality is looking like in-flowing into the lake."
The City of Saint John looks after the water-quality tests in the Loch Lomond lakes, but ACAP uses them to monitor the tributaries to the water supply.
MacKinnon said this process ensures there's nothing "coming off the land" that could impact water quality.
Forest health refers to the diversity of species occupying certain areas of the forest. Keeping a forest healthy also requires future planning to maintain and preserve the vegetation, MacKinnon said.
She said ACAP will be tracking which trees do well in a changing climate to preserve the lifespan of the forest and protect the watershed.