The state is taking applications for permits for river shacks. After Aug. 22, those without a sticker can be taken away and destroyed.
River shacks are floating abodes, often old campers or garden sheds, tied to trees or other objects in the rivers and lakes.
Little Pee Dee River on Horry County's border had among the worst infestations of the shacks.
A law passed in May allows river shack owners to get a $50 permit if the structure complies with the law and then keep it for five years.
After Aug. 22, any river shack without a permit is subject to being removed.
After Aug. 22, 2012, no river shacks will be allowed.
As of Monday afternoon, no permit requests had come in.
"If we get 100, I will be astonished," said Brett Witt, a spokesman for the state Department of Natural Resources.
A survey in 2005 found 135 river shacks, but a followup earlier this year found at least 30 more, with more moving in weekly as the law was under consideration.
Some of the shacks are hazards to navigation, and discharge raw sewage and dump ntetrash into the water. But until the law passed, there was no specific prohibition against them.
Permit applications must show the latitude and longitude of the structure or include a map of its location.
DNR law enforcement officers will inspect a river shack before approving it for a permit.
It must not be a hazard to navigation, or encroach on private property or a wildlife management area.
The law also requires river shacks to have marine toilets with a holding tank.
"Just because you apply for a permit does not mean you necessarily get one," Witt said.
Applicants can call DNR at 803-734-3857 or download a form at www.dnr.sc.gov/boating/waterstruct.html.