Large-scale wildfires that have ravaged Australia and the USA can cause a lot of water contamination. Contamination is especially true when heavy rains follow the fires, washing contaminants such as ash, toxins, and other metallic sediments into the nearby natural waterways.
These contaminants don’t just affect the water supply during the months surrounding the fire but have a long-term impact and make water harder to treat.
Mercury contamination is common, and many areas in Canada and the United States need to watch out for this.
Contaminated water from singed forests takes many years and is very expensive to treat. For example, water from a 2003 Hayman fire in Colorado took 15 years to treat, and issues in water quality can persist for many years.
The Western News reports that burn scars from the Colorado wildfires in 2020 have threatened its water supplies. According to the news, it was not until the following year, in July 2021, that the residents felt the impacts of the forest fires.
When heavy rains poured on recently singed Colorado forest – all 600,000 acres of it, it pushed sediments to nearby rivers and streams.
Water from the burnt forest was so murky that the town had to shut their valves that pump waters from these nearby rivers to avoid overwhelming its filtration system.
At the same time, city managers sent alerts to the towns 10,000 residents to minimize their water uses until sediments flowed downstream.
Extensive and severe wildfire in Canada and the US can increase drinking water production between ten to hundreds of millions of dollars.
The burden of paying for these costs is eventually passed on to taxpayers. In many rural small towns, the costs of paying for these municipality utility systems can be immense.
Residents are faced with either spending millions of dollars to filter these murky and toxin-laden water or shutting off their water supplies.
The Conversation weighs in on the topic with some suggestions on how to manage these risks:
“Therefore, governments need to seize existing opportunities, such as leveraging existing data and taking advantage of growing computing power, to measure wildfire risk to water supplies. A tailored wildfire-water risk reduction strategy can help achieve better source water protection, improve infrastructure and foster preventive disaster planning.
We will undoubtedly learn more as our knowledge of indigenous forest management practices improves. Instead of reinventing the wheel, we must try to keep water in the landscape by restoring wetlands and accept a helping hand when offered.”
As noted, indigenous practices to avoid large-scale wildfires such as controlled burn-offs and other strategies should be on the radar of the government agencies managing areas prone to catching fire.
Adopting environmentally-friendly practices like this can reduce severe wildfire incidents, especially in upstream forested areas, lower the water treatment bills, and better protect water services and infrastructures.
Collaboration and careful resilience planning will play an essential role in future forest watershed management.
Taking a much more comprehensive view of integrated resilience planning will assist in both improving resilience and in managing the longer-term costs of municipal water supply provision.