Rain still brings trouble to burn scar areas: "There's a new emergency every time it rains really hard"
As rain fell in Colorado's mountains Friday, concerns were renewed that it might bring a gush of mud, ash and debris-filled water downstream from the headwaters of the Cache La Poudre and Big Thompson Rivers as they ran out of the burn scars of Colorado's two largest fires in recorded history.
"There's a new emergency every time it rains really hard," said Sean Chambers, director of water utilities for Greeley. "There are still areas that were really severely burned both in Cameron Peak and East Troublesome. They're just having a hard time recovering," said Chambers.
Greeley has joined with other communities and with state and federal help has worked to mitigate some of the worst of the fire's damage to keep the water the city draws from both rivers for its water supply from getting too contaminated to draw and filter.
11 times so far in 2023, Greeley has had to shut down its draw of water intakes. It does have backup water in reserve, but the long-term problem continues.
There have been efforts to protect lives and property and to mulch moderate slopes to spawn regrowth, but some of the soil was so baked by the heat of the fire, it is considered hydrophobic, or mostly impervious to water.
"The areas that are still challenged as the areas that were really severely burned. And so there hasn't been any regenerative growth on those hill slopes," he said.
Forestry experts have looked at what happened, determining some of it might be expected as fire is natural process in Colorado's forests. But not entirely.
"The extent and the time frame was way out of the range of natural variation," said Daniel Bowker, forest program manager for coalition for the Poudre River Watershed. "Some of the areas once you get up into the sub alpine like lodgepole pines, spruce fir, they do burn at high intensity and will. That's not really something we're going to change."
But other forest areas can and do burn with lower intensity and with lower flame height, leaving the soil more intact for regrowth.
About $35 million has done toward projects to protect and restore areas burned in the Cameron Peak and East Troublesome Fires. But estimates of the overall cost go beyond $100 million.
"But it covers a relatively small number of acres and a relatively small amount of projects," said Chambers.
With over 400,000 acres damaged by the two fires, they can make efforts in one area, but heavy rain will fall in another drainage and bring down debris. There's even difficulty getting the work done.
"We just don't have the capacity all the way through the kind of supply chain the work force, the contracting, it's been a real struggle to get recovery out on the ground," said Chambers.
Work is shifting from the mulching done the first two years to the installation of things like post assisted log structures, in which locally sourced wood is driven into the ground or stream beds, then willows or other wood is weaved through it to create a barrier, like a strainer.
"Structures that function a lot like a beaver dam and they slow the water," explained Chambers. "They allow the sediment to drop out ,the water passes through and then the water comes down to us much cleaner than it would if these logs and wood structures weren't in the treatment."
There is less ash coming down now, but it can still be too much for water systems to process still. The work and the problems from two fires so large will likely go on for years into the future and as memories of the fires fade, sourcing the money to help could get harder.
