The fire is being contained near I-10 and Eldridge Parkway, just south of the Bear Creek Park.
Officials said there's no threat of this fire spreading and that it is currently 99% contained.
Authorities said 105 acres of the Addicks Reservoir have burned in this grass fire. HFD said they don't know the cause yet, but that arson investigators will look into this.
HFD Captain Beau Moreno said crews were called out to the area to check for smoke Sunday morning.
"When the units arrived, they saw that they had smoke down here," Cpt. Moreno said.
Cpt. Moreno said because of the cooler temperatures, the smoke was lying low, so they could not immediately find the fire. When they eventually found it later that morning, Cpt. Moreno said it was 100 yards into the wooded area.
"There's no way to drive a vehicle, and there was no way to get hoses up into that," Cpt. Moreno said.
So, he said crews tackled this differently and let the fire come to them instead.
"We light smaller fires that we know we can control and burn out everything that's going to be burning," Cpt. Moreno said. "That way, when the fire, the large bulk of the fire gets to us, there's nothing left to burn."
HFD said crews will be monitoring the fire until it's completely out, which could be another day or two.
"That smoke is lifted out of here now. The air quality has improved," Cpt. Moreno said. "There's no threat to the citizens. There's no threat of this extending."
Cpt. Moreno wanted to stress this was not a controlled burn.
On Monday morning, ABC13's SkyEye flew over the area, where fog blanketed the flames.
The U.S. Army Corps of Engineers manages the property, Houston fire officials said.
Officials reported no injuries or deaths and said they will continue to monitor air quality.
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