Coralville Lake is beginning to disappear as sedimentation builds up next to the dam. The lake has been vital to the Coralville community and its surrounding areas for more than 60 years.
A local nonprofit and the U.S. Army Corps of Engineers have determined that the man-made Coralville Lake may soon be disappearing due to sediment build-up along its dam and basin.
Friends of Coralville Lake, founded in 2016, help improve the lake together with the nearby neighborhoods. According to its website, the lake contributes more than $ 75 million to the local economy.
“The Friends of Coralville Lake were formed at the request of the Army Corps of Engineers to meet the challenges of funding and maintaining all activities in the area. One of those challenges involves recreation, ”said John Kounkel, president of Friends of Coralville Lake.
The lake is known for its campsite and recreational activities such as fishing, hiking trails, and boat ramps. Coralville Lake was founded in 1958 and has been essential to game and fishery management ever since.
Jon Kounkel, president of Friends of Coralville Lake, said the group is proposing three phases to preserve Coralville Lake.
The phases proposed for the recovery plan are:
- Make the community aware of the situation.
- Start a formal campaign to save the lake
- Execute the proposal to stop the degradation of the lake
Kounkel said the watershed around the lake needs to be addressed through the establishment of a watershed management authority.
“There are many different techniques you can use to reduce sediment load, such as silting basins or buffer strips, but it all starts with setting up a watershed management authority,” he said.
Coralville Lake could have an impact on Iowa City and the surrounding area, Kounkel said.
“If we can significantly reduce the lake’s sediment load and bring it back to its original state, we could provide better drought resistance to Iowa City and other downstream communities,” he said.
One method of reducing sedimentation is through mud traps. Kounkel said the lake has been muddy for the past few decades, creating a backlog of the water flow and dam of the lake and that no one has looked into the issue.
“Basically, a mud trap is just one way of stopping sedimentation before it continues flowing into the lake,” said Kounkel.
The Friends of Coralville Lake website states that if no precautions are taken to help the lake, the lake may become unusable in the next 10 to 20 years. The estimated cost of the plan is currently unknown.
Jonathan Wuebker, assistant operations manager for the Army Corps of Engineers, said the group is tasked with managing funds for Coralville Lake. He said the program was testing sedimentation in the lake. Every type of water column study is measured in parts per million for things like microcystins, E. coli, and sediments, he said.
“We are an agency that has a certain amount of dollars approved by Congress to administer certain aspects of the mission. Flood risk reduction, natural resource management and water supply are specific tasks for which we are authorized to manage the water level, ”said Wuebker.
Howard Goldman, operations project manager for the Army Corps of Engineers, said the lake’s problem is that the 3,000 square miles of Iowa River water goes to Coralville Lake and Dam, causing flooding and sediment buildup.
The first phase of the lake’s recovery is public awareness of its excess sediments, he said.
Goldman said the real key is to slow the Iowa River watershed so it can get into an aquifer rather than the lake.
“But that’s not an efficient way of dealing with growth and things like that. You have to build this stuff and get the water out, ”Goldman said.
Goldman said another challenge is finding a balance within the community to repair the lake.
“Every city wants to grow and see its community thrive,” Goldman said. “It’s a recreational problem, it can be a problem for the local economy and housing.”