Custer State Park
According to the Custer State Park Superintendent the Legion Lake fire was started by a power line that was knocked down by a falling tree.
It's not an uncommon problem in the forest.
With a dry ground and strong winds, conditions were just right to fuel the flames.
But KELOLAND's Angela Kennecke has uncovered the owner of those power lines, Black Hills Energy, previously known as Black Hills Power, was the same company whose power lines sparked another massive wildfire in western South Dakota, not that long ago.
87 landowners accused Black Hills Energy of causing a massive 2013 wildfire called the Oil Creek Fire and claimed the company hid crucial evidence in the case. The State of Wyoming also demanded the power company pay for the costs to battle the fire and for damage to public lands.
The lawsuits were settled last year out of court. Details of the settlement are not public.
Now a Black Hills Energy line is the likely culprit of the latest devastation in the Black Hills.
Investigators have no doubt about what started the fire in Custer State Park.
"Somebody actually saw the tree come down. He said instantly the fire was the size of a Volkswagen and took off from there," State Wildland Fire Suppression Director Jay Esperance said.
Utility companies are required to keep the right of way around their power lines clear to prevent trees from falling on them, but this tree spanned a good distance according to the fire investigator.
"He identified the tree, he identified it was 54 feet from the tree is where it struck the line," Esperance said.
Other trees also fell in the wind causing power lines like this one, which has been patched, to go down as well.
South Dakota state law says utility companies can be held accountable if they are negligent in maintaining those lines, but that can be tough to prove.
However in 2013, investigators in the Oil Creek Fire determined a damaged power pole owned by Black Hills Energy fell on a tree igniting the wildfire.
It spread over 100 square miles of forest and ranch land in Wyoming, just west of the Black Hills,
Nationwide, power lines also often cause fires.
In California authorities determined that the 2015 Butte fire that killed two people and destroyed more than 500 homes was caused by Pacific Gas & Electric improperly maintaining its power lines.
In Washington State wildfires are often caused by downed power lines. In 2010, officials held the utility company liable after a tree fell on one of its power lines.
And In Texas, more than 4,000 fires were caused by power lines over a three and a half year period, costing hundreds of millions of dollars.
KELOLAND's Angela Kennecke spoke with a representative from Black Hills Energy who said they are unable to comment on the cause of the fire saying it is only speculation that it was caused by one of its power lines going down.
Black Hills Energy says it has a comprehensive vegetation management program around its power lines and does weekly line patrolling.
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