Quarry Fire investigated as arson as Chatfield Reservoir reopens to Colorado boaters

The Quarry Fire burning in Jefferson County is being investigated as arson. The fire is 431 acres in size and was 4% contained as of Friday morning. 

The fire started near the intersection of West Deer Creek Canyon Road and Grizzly Drive on Tuesday night. According to the Jefferson County Sheriff's Office, the fire grew slightly overnight Thursday into Friday in an open meadow that needed to undergo fire mitigation. 

Investigators are now conducting an arson investigation on the Quarry Fire. 

"The point of origin is on Deer Creek. It's just up above Grizzly Drive and those switchback areas. From there. I can share that right now we are actively conducting what we are calling an arson investigation. And the reason it's an arson investigation is that we preliminarily believe that this fire is human-caused in some manner," said Kevin Bost with the Jefferson County Sheriff's Office Criminal Investigations Division.

Hundreds of families remained out of their homes on Friday. 

The rough and steep terrain makes the Quarry Fire difficult to fight. An additional hotshot crew arrived on Friday to help fight that fire. 

"If you think about just the steepest sort of mountain that you can climb and how it's rocky, very rocky. So trying to dig in that rock, trying to do it on an angle that is so severe, and to try to do it in the heat that we are experiencing right now. These are very, very difficult situations," said Karlyn Tilley with the Jefferson County Sheriff's Office. 

Officials said they are cautiously optimistic in containing the fire. 

After the fire started, Chatfield Reservoir was closed to boating and water recreation to make way for firefighting resources.  

Because of the need for water from aerial teams, Colorado Parks and Wildlife has closed Chatfield Reservoir to boating. That closure was lifted on Friday morning as Quarry Fire operations with the belly planes finished. 

According to CPW, helicopters may still be in the area but are able to work around the boats.