Acres of mud strewn with dead fish greeted hundreds of eastern Iowa residents Monday after a weekend dam break left their lakefront properties overlooking little more than a small stream.

The Lake Delhi dam in Delaware County gave way under the rapidly rising Maquoketa River on Saturday, decimating the nine-mile-long lake and adjacent property values.

"The water's gone, dead fish are laying there on the bottom — it's a pretty nasty looking scene," said Irv Janey of Marion, who owns a condominium on Lake Delhi. "It was a beautiful recreation area and to see it drained, it just makes you sick."

Heavy rains last week forced the river to unprecedented levels, causing earthen portions of the dam to collapse and sending a torrent of water rushing downstream. The concrete section of the dam remained intact, but the swollen river damaged about half the 1,000 homes and cabins above it. The lake quickly emptied.

"We have over $100 million in homes on the lake and none of them are worth what they were when they had water in front of them," said Jim Willey, director of the Lake Delhi Recreation Association. "You have a home with a lake or a home with a mud flat.

"What might have been a $500,000 house is probably worth only a quarter of what it once was."

Property owners clearly hope the lake will be restored. But it is up to the association to decide whether to rebuild the dam, built in 1927 to produce hydroelectricity. The lake is now used solely for recreation and the association members pay dues to maintain it.

Board members were meeting with local, state and federal officials Monday, Willey said. He said the group is committed to recovering the lake, but acknowledged funding could be a major obstacle and any plan would be on hold until officials know whether a federal disaster declaration will be granted.

Iowa Homeland Security and Emergency Management Director David Miller said the Lake Delhi dam likely will be eligible for federal assistance because it received aid after major flooding in 2008. If approved, the Federal Emergency Management Agency would pay 75 percent of dam's costs. The state would pay 10 percent and local government would have to pay the 15 percent balance, Miller said.

Miller said any publicly funded efforts would receive close scrutiny.

"When we do repair projects, they are often subject to environmental reviews and maybe a historic review and maybe other regulatory reviews depending on where they get their funding," he said.

Work to refurbish the dam, damaged by flooding in 2008, actually was under way when it collapsed, Willey said.

"More water came down than ever had been planned before," he said. "Things were different when it was built, the watersheds were different, field drainage was different, we're working with a situation that the designers of the dam couldn't have foreseen."

Downstream in Monticello, the water from the Maquoketa River was receding Monday. About 50 homes and 20 businesses took on water over the weekend after the dam collapsed.

Water remained in some flooded areas but had fallen dramatically from reaching the eaves of at least one business Saturday, said Brenda Leonard, the Jones County emergency management coordinator.

Leonard said the county relies on the Lake Delhi dam for river level measurements and were isolated after the dam broke. There are no river gauges between Manchester to the north and Maquoketa to the south, she said.

"We had no idea what was coming," she said. The state patrol had to fly over the area to alert officials what was headed their way, she added.

Back at the now-barren lake, residents were left with little to do but wait.

"We only have a summer cabin, but for people who built those beautiful homes up there, the lake, the beautiful view, that's why they built up there," said Judy Leeper of Clarence. "It left everyone heartsick."