Effects of wilfire on landscape, wildlife go beyond the flames
The potential impacts of the fires currently sweeping through parts of the state — and forecast throughout this hot, dry summer — will not end when the flames go out. And, ironically, the water on which humans and wildlife depend may be one of the key resources at risk.
After a burned hillside is left denuded of trees and brush, it becomes a potential ground zero for mudslides and other forms of erosion once rains begin later in the summer.
That erosion can deposit large amounts of ash and what was once a forest floor into rivers and streams, potentially suffocating fish populations and hampering drinking water supplies.
Outside Glenwood Springs, for instance, large flows of debris sloughed off burned slopes following major fires in 2002 and — covering some of I-70 and damming part of the Colorado River — in 1994.
For Colorado’s fish, wildfires and any resulting impacts are nothing new, of course, but sediment can become just another hazard for the endangered and threatened fish that call the state’s streams home.
In New Mexico, officials were working to move threatened Gila trout out of streams that could be impacted by fires burning in that state this week.
Currently, none of the fires burning in Colorado are impacting streams where similarly imperiled fish live, said Randy Hampton, spokesman for Colorado Parks and Wildlife. But 10 years later his agency is still working to fully bring back fisheries in areas impacted by 2002’s Hayman fire, south of Denver.
“Wildfire is both good and bad for wildlife,” he said, noting that, for the most part, it creates better habitat for forest animals. “But most of the negative impacts will be on fish.”
For three years following that blaze, ash- and sediment-laden runoff would wash off the burned area following every rain, potentially clogging the gills of and suffocating fish in the South Platte and other rivers, he said.
That slurry and ash creates short-term problems for fish.
“That’s because it’s not water. Anything in a large quantity where there’s not enough water to thin it out would have an impact” — even, say, iced tea — Hampton said.
The only thing that can be done is to work with the U.S. Forest Service and other groups to revegetate the burned areas and quickly and effectively as possible.
That also is the primary tactic for preventing fires’ posthumous impacts on the water humans need.
Once a fire is put out, acres of ash remain on the ground. If that fire is in a watershed, such as Grand Junction’s along Kannah Creek or Palisade’s watershed just north of that, rains can wash that ash and mud all the way down to the intake pump that funnels the water into the pipelines that bring it to reservoirs.
In July 2011, a small fire burned 40 acres of watershed land not far from that intake. In the weeks that followed, Slade Connell, Grand Junction’s water supply supervisor and the man responsible for ensuring water continues to flow, clean and unimpeded, through the watershed, checked the burned area every day for runoff of ash and other debris.
If runoff had started heading toward Kannah Creek or its tributaries, he would have temporarily shut off the intake, allowing the runoff to continue downstream rather than through the pipes to the reservoirs—not too difficult of a solution, but one that requires frequent monitoring.
Grand Junction also is lucky in that its water comes from three basins — Kannah Creek, the north fork of Kannah Creek and Whitewater Creek — so “if we have a disaster in one of these basins, we can rely on the others,” according to the Greg Trainor, the city’s utilities director.
But the potential still exists for a massive, watershed-wide fire. As the Daily Sentinel reported in April, conditions could be just right for catastrophic fires this year, though utilities officials are confident that they can cope with even massive fires by relying on the different basins or shutting off the intake.
Trainor said in April that, in theory, they could shut off all water into Juniata Reservoir, the city’s largest, for a year and still have enough in that reservoir alone to meet the city’s needs.
But management efforts have tried to reduce the need for those last-resort measures.
In July 2008, the Grand Complex fire burned about 1,500 acres of watershed land along Coal Creek. That fire coincidentally took care of a portion of the prescribed burns that had been slated for the watershed in order to limit the potential of a much bigger fire. Crews worked daily to herd the blaze away from tributaries to Kannah Creek and to carve the nearly impassable brush into a mosaic intended to slow and direct the fire to where it would bring the most benefits and lowest impacts.
Most fires in the watershed in recent decades have been small, leaving overgrown stands to gradually get bigger, thicker and potentially more dangerous once they eventually catch fire, so in 2007, the city entered into a fire fuel-management plan with the U.S. Forest Service to control-burn, hydro-ax and hand-thin the areas of most critical concern.
The area impacted by the Grand Complex fire was reseeded as quickly as possible, Trainor said, and, though there were some problems immediately following the blaze, he said that there have been no problems with runoff-impacted water recently.
“We’re very fortunate that we’ve got these three basins and that we haven’t had a fire so catastrophic that we couldn’t overcome it within a few years” he said.
This article is part of a grant-funded project in cooperation with Colorado Mesa University to report on issues of environmental concern.