Black Hollow Flood : Fire Burn Scar Creates Perfect Conditions for Disaster
On July 20 , 2021 , Todd Boldt was fly fishing with a friend on the Poudre Canyon when he started to see lightning
in the distance . Soon after , it began sprinkling .
“ I had just snapped off a fly from my rod , when I looked at my friend and said , ‘ Hey , let ’ s get out of here ,’” said Boldt , who leads the Emergency Watershed Protection Program for the Natural Resources Conservation Service and is currently assisting the City of Greeley with is fire mitigation work . “ Honestly I was more worried about getting struck by lightning than the drops of rain .”
“ There was this guy who comes flying
down the road and he stops and says , ‘ It ’ s flooding up there . Houses and cars are in the river .’” Boldt recounted . “ I looked over at my friend and said , ‘ We ’ ve got to get up there ,’ and he said , ‘ Are you nuts ?’”
Understanding the danger and likelihood of flash floods following a forest fire , Boldt immediately knew the situation was serious . But even for him , this knowledge did nothing to prepare him for what he was to soon witness .
On their rush up the canyon , Boldt and his friend recall the river looking like a sea of black sludge with logs and trees . “ Then we got to Black Hollow , and it was unbelievable what we saw ,” he said .
What they saw was the immediate aftermath of debris flow so forceful it pushed entire homes into the river . Rainfall on the burnt mountainside eroded steep slopes and began picking up sand , gravel , trees , and boulders , gaining energy and power as it moved into small channels before eventually transforming into a debris flow in Black Hollow Creek .
“ That would never have happened if the land wasn ’ t burnt ,” said Chelsey Heiden , a water resources engineer with Ayres , who has been working on the post-fire mitigation efforts .
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