A storm-weakened 14-mile sand levee that was partially breached by floodwaters, turning one rural Wisconsin neighborhood into a virtual island, held overnight, an emergency official said Tuesday.

Greg Matthews, spokesman for the Wisconsin Department of Natural Resources, said Monday night he was "cautiously optimistic" the levee protecting Blackhawk Park would hold. Still, he said it would likely be at least another day before the water level drops.

Columbia County Emergency Management director Pat Beghin said DNR inspectors did not discover any new breaches of the levee overnight and that they would continue to monitor it Tuesday.

The century-old earthen dike, part of a 14-mile berm, separates Blackhawk Park and the city of Portage from the Wisconsin River. But it rose so high and so forcefully following days of heavy rain last week that it surged around the dike and poured into the bottom lands around the neighborhood, said Steve Miller, director of the DNS Bureau of Facilities and Lands.

The flooding enclosed Blackhawk Park and engulfed the only access road into the neighborhood in Caledonia just southeast of Portage. A few homes in low-lying areas were surrounded by water, but most of the houses stood on high ground and were not affected.

On Sunday, emergency workers asked the approximately 300 people living in the neighborhood to evacuate their homes, warning that they could be cut off by the burgeoning river. Beghin said about 25 homes in Blackhawk Park remained occupied Monday.

Gov. Jim Doyle declared a state of emergency for Columbia County Monday after the Wisconsin River reached a record high level. The declaration directs state agencies to assist in recovery efforts.

Much of the levee protects forest and farmland, but a breach in the Blackhawk Park portion could wash away the access road altogether. Beghin said that under that worst-case scenario, remaining residents could be stranded for up to a week.

DNR workers were using sandbags to control the seepage, and Matthews said the effort seemed to be working.

Forrest Travis, a 53-year-old part-time construction worker, said he spent Sunday night at his fishing camp and didn't have any plans to go anywhere, even as water rushed across the gravel service road a few steps away.

"I'm not worried about it," Travis said. "It would have to get a lot higher to get where we're standing."

Diana O'Neill, 56, a retired De Forest police officer, evacuated Sunday. On Monday, she inched her truck along the access road, creating a wake, to get back to her house.

Her place was still dry when she arrived. She grabbed three dozen eggs and her Chicago Bears shirt for the Green Bay Packers-Chicago Bears game Monday night and inched her way back out. The water was easily an inch higher than when she drove in.

"I'm kind of a risk-taker," she said. "If it wasn't for the road being overrun I would have stayed here. I've got stuff to get done."

The Wisconsin River runs along the outskirts of Portage, a city of about 10,000 people some 40 miles north of Madison that touts itself as "Where the North Begins." The river had overflowed its banks by dozens of feet, pouring onto low-lying roads.

Residents ventured to the water's edge to watch as the river surged by.

Staring at the churning water, Shawn Schweitzer, 39, of Portage, said that usually at this time of the year the water is so low you can nearly drive across the river bottom.

"Now it would be bye, bye," he said as he watched the current swirl and eddy. "I've never seen it move this fast."

State and local officials were so concerned about the integrity of the 14-mile levee system homeowners built in the 1890s, a group was established to study it.

The group recommended in 2007 that because the levee was so unsafe and unable to protect against flooding, property owners should be offered incentives to move.

Miller said little has been done to make changes since the report came out.

National Weather Service hydrologist Bryan Hahn says the Wisconsin River reached a record level of 20.59 feet Monday at 6 a.m. That breaks a previous record of 20.50 set back in 1938.

The river was expected to hold steady through Tuesday, Hahn said, then slowly decline over the next seven days.

In South Dakota, water levels in the storm-bloated Big Sioux River were stable Monday after up to 4 inches of rain last week pushed the waterway over its banks along a 50-mile stretch from Brookings to Sioux Falls. About two dozen homes in Renner, the worst-hit town, were affected, Renner Fire Chief Mike Schmitz said.

Separately, Minnesota Gov. Tim Pawlenty reached an agreement with legislators on a special one-day session next month to approve relief money for people affected by floods after heavy rain last week caused serious flooding in that state.


Associated Press Writers Jeff Baenen in Minneapolis and Scott Bauer in Madison, Wis., contributed to this report.