TRAVERSE CITY — A copper-brown sediment plume spews from Hatlem Creek and spreads into Glen Lake whenever several inches of rain fall.
“It’s incredible,” said Peter Anderson, president of the Glen Lake Association, a nonprofit dedicated to protecting and preserving Leelanau County’s Glen Lake area. “There’s nothing bad in it, we’ve had it tested. It’s just good, old-fashioned silt.”
Members of the Glen Lake Association raised nearly $300,000 to dredge Hatlem Pond, through which water flows through before spilling into Glen Lake. The project will remove sediment and water from the pond and keep sediment from flowing into Glen Lake.
“In this dredging process, we’re going to allow the pond to regain its original bottom so it can catch future sediments coming from upstream into the pond and not allow water to transport sediment into Glen Lake,” said Rob Karner, project manager and watershed biologist for the Glen Lake Association.
Dredging is slated for two phases, one this year and one next summer. Phase one is scheduled to start May 27 and should last about two weeks. Failure to dredge the pond could cause the bottom of the larger Glen Lake to soften over several years.
The 7- to 8-foot deep Hatlem Pond is filled with about 6.5 feet of sediment, or enough to fill 950 dump trucks, Anderson said. The man-made pond, located to the south of Big Glen Lake, started to fill with sediment when a dam was put in about 50 years ago.
“Because of an artificial dam that was put in, we get excessive sediment transport during rain events and it’s unnatural to have that sediment transport,” Karner said. “Imagine the dam not being there. The sediment transport would be even and gradual.”
Sediment can carry E. coli and transport phosphorus and nitrogen.
Crews will hydraulically dredge, or suck up, water and sediment from the pond and deposit it into an adjacent holding pond on private property.
The water should absorb into the ground, evaporate from the silt or will be decanted back into the water system, Karner said.