Lake Darling dam project about 30 days from completion
BRIGHTON (GTNS) — After falling a year behind on the Lake Darling project due to weather, workers constructing the new dam for Lake Darling are within a week of completing the main structure and about 30 days from completion of the total dam project.
Vance Polton, an Iowa Department of Natural Resources fisheries management technician, said for this year the project has been running ahead of schedule with dry weather over the last week.
“When you rebuild a dam, you also have to put in an emergency spillway, and you have to grass everything,” Polton said. “Obviously the seeding won’t be done this year, but as far as making everything neat and tidy, with some good weather, within four weeks they could have everything buttoned up.”
He said the grass seeding to seal the project and keep the soil from eroding would be done in the spring. He said this late in the year, the seed wouldn’t have a chance to grow.
Polton said the progress of the work depends on the amount of rain the area gets as to how quickly it can be done. He said the contractors hope to get the dam work done before the ground freezes this year. He hopes the project will be complete so the lake can be refilled next spring.
The dam, Polton said, is made of red clay with a bit of sand in it. The top is about 12 feet across by about 500 feet long by 40 feet high. Most of the dam will be under water, he said. The dam is located on the far northerly end of the park.
After the dam is completed, Polton said the other part of the $4 million project, which removes silt from the lake — about 293,000 cubic yards — also is ongoing. The contractors have about 65,000 yards out already, much of which is from the campground area. After that area is done, the contractors will begin working on the main area of the lake. This will be done in the spring.
Polton said a boat ramp would also be built next spring before the lake fills.
“Right now if everything goes well and the weather doesn’t give us a wet early winter, we’re hoping to have everything done and catch the June rains to fill the lake,” he said. “Maybe, if we are lucky some of the May rains. If everything went really well, we may even be looking at catching the spring snow melt.”
The lake was drained in November 2008 for the project. He said the problem with the dam, and the main reason the lake was drained in the first place, dealt with the old concrete spillway — a low spot in the dam to allow water to run over the top of the dam — leaking about 3 million gallons of water a day. He said this is the equivalent of a one-acre farm pond. He also said during a dry spell the lake would go down quickly. He said in 2002 the dam failed an inspection.
“Our main hassle getting this started in 2009 is that we had two very wet years,” Polton said. “Our average rain fall is about 34 inches. In 2009 we had 54 inches of rain. Last year, we had right around 56. When you have 20 inches of rain over average, you have what we had — the lake filled up 10 times between 2009 and February. It slows down work when you are trying to put a hole through the dam and the lake is full of water.”
The project included removing the old spillway and extending the dam across the lake. Polton said when the spillway had been constructed on limestone, which eroded and allowed water to get out. He said in modern times such spillways aren’t made anymore. The new clay spillway won’t erode, he said.
Fay Vittetoe, president of Friends of Lake Darling, said she is happy with the progress that has been made. She said local people are regularly driving through the park to see the progress being made on the lake.
“Its amazing to see that amount of earth moving equipment,” she said. “I think this is the point we want to be at. We hoped we had been there a few years ago, but it is finally happening. We are going to have a premiere fishing lake back.”