In the mountains above Fort Collins, about a two-hour drive from downtown, crews are deep in the woods and hard at work to protect the city鈥檚 water.
A significant portion of Fort Collins鈥� water supply starts as alpine snow, trickling down through forests of tall conifers before joining the Cache la Poudre River. From there, the water flows to the treatment plants where it's cleaned up and pumped to kitchen faucets across town.
So when these notoriously wildfire-prone forests light up, it can deal big consequences to water users far downstream. A coalition of state and local agencies is trying to prevent that.
The work targets the area around Michigan Ditch. It鈥檚 a five-mile canal, built more than 120 years ago, that carries water from the Michigan River to the Poudre. You can trace its route along the hillside while driving over Cameron Pass. If you鈥檝e ever hiked the popular American Lakes trail in State Forest State Park, you鈥檝e likely stepped across it.
The water flowing through Michigan Ditch makes up 11% of Fort Collins鈥� supply. If the steep, densely forested hillsides catch fire, the canal will fill up with ash and sediment, making its water difficult and expensive to treat.
That鈥檚 why hulking yellow trucks are picking through these forests, hacking down burn-prone trees and making it harder for a wildfire to reach this key piece of water infrastructure and pollute the clear mountain snowmelt within it.
鈥淏y mitigating the risk of wildfires and erosion and sedimentation of the ditch, we're building resilience so that these systems and water operators can keep working even when wildfires come,鈥� said Courtney Young, forest health and wildfire mitigation program administrator for the Colorado Department of Natural Resources.
There鈥檚 good reason to believe that wildfires could cause trouble in this area. The state鈥檚 largest-ever wildfire, the Cameron Peak Fire, burned just down the road in 2020, causing lasting harm to water quality in the Poudre River. The second largest, the East Troublesome Fire, burned about a dozen miles away from the ditch in the same year. The 2012 High Park Fire also burned huge swaths of hillsides above the Poudre.
That likelihood is why a coalition of different government entities 鈥� including the City of Fort Collins, the City of Greeley and the Colorado State Forest Service 鈥� is spending nearly $3 million on forest work around Michigan Ditch.
鈥淚t's not if a fire burns, it's when a fire burns,鈥� said Jared Heath, senior watershed specialist with the City of Fort Collins. 鈥淲hen that fire burns through here, we're going to see lower fire burn severity, lower soil burn severity, and ultimately, if we can reduce those impacts, we can reduce the impact of sedimentation and erosion into our drinking water supply.鈥�
That sediment would be harmful to consume, and water treatment plants need to roll out more rigorous treatment to keep it out of the drinking supply. Experts say the cost to do so far outpaces the cost to protect the faraway canal from wildfires.
鈥淎t treatment plants, the cost to remove those pollutants is much higher, through chemical addition or additional treatment processes that are in the millions or sometimes tens of millions of dollars,鈥� said Nicole Poncelet-Johnson, a water specialist with the city of Fort Collins. 鈥淪o this small investment of a couple million dollars prevents those kinds of investments farther downstream.鈥�
This story is part of ongoing coverage of water in the West, produced by 萝莉少女 in Colorado and supported by the Walton Family Foundation. 萝莉少女 is solely responsible for its editorial coverage.
