The Dakota Fire is burning near the Dakota Point Recreation Area at Sheridan Lake, about 15 miles southwest of Rapid City.
Authorities say it has reached about 300 acres in size, with 30 percent containment.
Some 60 firefighters are battling it on the ground and in the air. The cause is being investigated by the U.S. Forest Service.
RAPID CITY, S.D. (AP) - People in 18 homes near Rapid City have been told they might have to evacuate due to a forest fire that continues to grow.
Authorities say it reached about 200 acres in size Wednesday afternoon, with no containment.
Sheridan Lake Road has been closed from the Spring Creek Picnic Area to the North Boat Launch Area.
Fire Planning Chief Chris Stover says that crews are trying to keep the fire contained to the boxes on the map, and so far their lines are holding.
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