Floodwaters slowly subsided in several northeastern Oklahoma communities early Wednesday, but weather forecasters predicted more flooding problems as swollen lakes and reservoirs reached capacity.

The worst flood damage Wednesday was in Miami, where the Neosho River crested at about 29 feet, its highest stage since 1951.

"We're starting to see an average drop of about a half-inch every hour," City Manager Mike Spurgeon said early Wednesday.

A shelter set up in the city housed about 55 people Tuesday night, and flood damage was expected to impact about 600 homes, Spurgeon said.

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"We started giving notification to people early Monday morning, so we are really fortunate it wasn't a flash-flood situation and we had time to warn people," Spurgeon said.

Rescuers used boats to rescue about a dozen residents, but most of those were people who waited too long after being warned to evacuate, Spurgeon said.

About 50 Oklahoma Army National Guard troops worked 12-hour shifts providing security in flood-ravaged neighborhoods.

Floodwaters continued to recede Wednesday near Bartlesville, where hundreds of residents were evacuated earlier in the week when the Caney River flooded its banks. But further downstream, near Collinsville, the river level continued to rise and more flooding was expected to impact a handful of homes there.

"It does look like the worst is over, but we're still keeping an eye on Collinsville," said Al Hong, a hydrologist with the National Weather Service in Tulsa.

A 42,000-gallon crude oil slick that spilled into the Verdigris River during flash flood that hit a refinery in Coffeyville, Kan. late Sunday had mostly dissipated, and there was no indication the oil went into Lake Oologah, a water source for the City of Tulsa, officials said Wednesday.

Aerial assessments Tuesday showed no signs of the slick, and experts believe the oil was filtered by trees and vegetation upstream from the lake, said Skylar McElhaney, a spokeswoman for the Department of Environmental Quality.

Meanwhile, creeks and rivers swollen from recent rains continued to flow into state lakes, more than a dozen of which continued to rise Wednesday and were expected to crest within the next few days, the U.S. Army Corps of Engineers reported.

The biggest concern was at Lake Texoma along the Oklahoma-Texas border, where water was projected to spill over the Denison Dam on Thursday, said Bryan County Emergency Management Director James Dalton.

"(We're) warning residents along the Red River to move all livestock, equipment and other necessary belongings to higher ground," Dalton said. "We are also urging residents to have an initial evacuation plan, should conditions threaten homes in the area."

It will be the third time in the history of the lake that the spillway overflowed. It also occurred in 1957 and 1990, although Dalton said this year's crest projection is 640 1/2 feet, about 4 feet less than in 1990, when major flooding occurred.

More than two weeks of soaking weather has caused widespread flooding in Texas, Oklahoma and Kansas. The weather has been blamed for 11 deaths in Texas in the past two weeks and two people are missing.

While the rain had moved out of Oklahoma, rain fell along much of the Texas Gulf Coast during the morning and the weather service said more was likely from South Texas north to the Dallas-Fort Worth area.

"We're going to see one of our heavier rain days of this event," meteorologist Monte Oaks said Wednesday morning in the weather service's Austin-San Antonio office.

At least 1,000 people were out of their homes throughout southeast Kansas, said Sharon Watson, spokeswoman for the Kansas adjutant general.

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