By Sterling McGinn

A dam situated more than a mile west of the source of the Manistique River controls the water level on Big Manistique Lake. When the lake level recently dropped to the lowest point in roughly a decade, property owners had questions. Who controls the dam? How deep should Big Manistique Lake be?

“People can’t get their boats off their lifts,” said lake resident Jim Mattson. “If you go to all the boat landings, they are all low—if you have a good 18-foot fiberglass boat and a higher trailer with rollers, you are not going to get it off at some of the launches.”

Big Manistique Lake covers 10,130 acres and is shared by Luce and Mackinac counties. Its lake level has been the subject of recurrent controversy. The discussion renewed in recent weeks after some residents took to social media to discuss the lake’s low level this summer. Some residents say the lake is currently the lowest they’ve ever seen; others can remember years when it was even lower.

The dam was built out of wood in 1948 and was replaced in 1978. The base of the dam is built at 681 feet above sea level, with five feet of boards that are removed in the spring and replaced in the fall.

The dam is overseen by both the Luce and Mackinac County board of commissioners with one commissioner from each board representing the Manistique Lakes Citizens Advisory Committee. The commissioner from Mackinac County usually resides in Portage Township, while the Luce County commissioner lives in Lakefield Township.

Three citizen members from each county are appointed to serve under the commissioners to ensure the dam is operating correctly and that there is no leakage. Mattson serves on the committee.

Members of the committee are the only authorized personnel permitted access to the dam site. Those committee members are appointed yearly at the Luce County and Mackinac County board’s organizational meeting held in January. Tampering with or trespassing at the dam may be considered a felony and violators will be prosecuted.

The U.S. Army Corps of Engineers set the lake level at 686.0 feet long ago, and a court order in 1948 holds that the Big Manistique Lake should be kept at 686 feet above sea level.

Another order was filed on June 5, 1978, reading: “It is ordered that the normal height and level of the waters of said Manistique Lake being fixed at 686.0 feet above sea level.” The court order was filed by Circuit Judge William Hood.

This spring’s rapid thaw caused considerably high water levels, causing erosion to the shoreline.

“I don’t think anybody was happy with the water level this spring,” said John Bergh, who also serves on the dam committee. “There was so much runoff—my front yard was wet, and it kills trees when the roots are buried in water.”

Spring water levels aren’t easily controlled by the dam, and because all Manistique lakes flow into the Manistique River sometimes river levels are so high that the river flows backwards into the big lake.

“There is nothing we can do about the spring level,” Mattson said. “This dam only controls the summer level.”

In the fall, committee members remove the top row of boards from all bays and two boards from the second row of boards. The boards are replaced in the spring.

During the summer, the level management is maintained by removing boards to bring the water level to the prescribed level if the lake is high.  If the lake level drops, boards are added above the top row to hold more water to bring it up to the prescribed level.

Portage Township Supervisor Don Reed said the lake was kept at artificially high levels for the past 7-10 years.

“By court order, 686 feet is the set level of the lake,” Reed said. “That is elevation…some think the elevation of 686 at the lake is different from the elevation of 686 at the dam…elevation is elevation,” he said.

Mattson feels that the boards were incorrectly pulled this spring, resulting in the low water level on the lake this summer.

“When we put the boards back in the way they should have been, it stabilized it,” Bergh said. “Now it [the lake level] is finally coming back to where it should be.”

Reed feels the lake is near what it should be now. “It is going to fluctuate with rain or with a drought,” he said.

Mattson and his fellow committee members are hoping that people understand how the dam works and what the process is to maintain the set water levels. “All we want to do is get on the same page with everybody,” said Mattson.