STREATOR -- A popular white-water stretch of the Vermilion River northwest of Streator has been closed by a cement company's owners, who said they will begin enforcing a trespassing ban on the part they own.

"We've had people pretty upset" about cancelling rafting plans, said Pat Semmler, who helps her father, Bob Horbst, operate Vermilion River Rafting in Lowell, between Streator and the river's end at the Illinois River in Oglesby.

The river was down to 1½ feet before the Independence Day weekend, well below the four feet considered ideal for the nine miles of rapids, she said. People, however, still wanted to make the trip, she said.

Last week, Buzzi Unicem Co., formerly Lone Star Co., a large cement firm that owns both banks of the river as it flows northwest through Wildcat Rapids, announced it would enforce its trespass ban after two people drowned in separate, recent incidents.

Under Illinois law, non-navigable rivers and its banks can be owned privately, said Chris McCloud of the Department of Natural Resources. A company is within its right if it wants to ban trespassing.

A river is non-navigable if commercial traffic cannot use it.

"They own the river," he said. If landowners contact DNR about enforcing the ban, the agency can make arrests.

Semmler said she hopes her father is able "to work something out" with the cement company to allow the rafts to pass by. The rafts are put in and taken out on their own property, though about a third of the rafting trip is on Buzzi property, she said.