Marshall Dam

An historic postcard showing the Masrhall Dam millpond. Courtesy city of Marshall.

(Courtesy city of Marshall)

MARSHALL, MI -- Marshall officials will be weighing the pros and cons of repairing or removing the city's 124-year-old dam across the Kalamazoo River, a decision that will cost money whichever way it goes.

And because the dam has been a part of the city's history and landscape for so long, there are more than financial considerations involved.

The city announced Thursday it is seeking professional engineering services to help decide the dam's future by determining the costs associated with repairing and maintaining the dam versus costs of removing it entirely.

Both options are complicated -- by the polluted sediments currently held in place by the dam, the long history of the mill pond and the longer history of the free-flowing Kalamazoo River, and the benefits and costs of generating electrical power.

Ed Rice, director of utilities, said the city-owned dam generates less than 1 percent of the total energy requirements for Marshall. The city operates the dam and associated facilities under a permit issued by the Federal Energy Regulatory Commission (FERC), and has used the facility to generate electricity for many years.

As it sits, the sediments that have accumulated behind the dam pose no immediate threat to the river downstream or Lake Michigan, where the Kalamazoo River empties, said Lucus Trumble, a dam safety engineer with the Michigan Department of Environmental Quality.

The trouble is, Rice said, federal inspectors uncovered some deficiencies that need to be addressed, soon, to prevent the dam from being damaged or destroyed during a heavy rain event.

Troubles if the dam fails

The dam is in need of significant construction upgrades which were determined as a result of FERC-required dam structure studies performed in 2012, according to Rice.

If the earthen embankment is washed out or the dam fails entirely, apartment buildings and the downstream boardwalk could be inundated, he said.

In addition, there would be environmental problems. Preliminary tests show the sediments are contaminated with a variety of industrial pollutants.

To avoid the possibility of these woes the city must repair the dam, or take it out entirely if it wishes to avoid the continued cost of upkeep.

"There's a sizable bill whether they maintain the dam or take it out," Trumble said. "The city is seeing which option is best, moving forward, for its constituents."

Marshall officials have released a request for proposal to select engineering firms across the region for recommendations and work plans addressing the future design, according to the news release.

"The City Council has not made any decisions regarding the future of the hydro dam and will thoroughly evaluate each proposal," said City Manager Tom Tarkiewicz."We are taking a proactive approach to this project to learn what needs to be done. We are keeping an open mind and exploring all of our options."

According to city estimates, rehabilitation of the hydroelectric dam could require lowering the water elevation of the city's millpond -- created by the dam's initial construction -- by more than six to eight feet, exposing the river bottom to air.

Preliminary tests show the sediment contains elevated levels of heavy metals and other chemicals, most likely deposited in the river over the course of the dam's long history.

The silt contamination has no connection to the July 2010 Enbridge oil spill in the Kalamazoo River.

City officials have consulted with members of the Calhoun County Health Department and state environmental regulatory agencies, including the Michigan Department of Environmental Quality, the Michigan Department of Natural Resources, and the Michigan Department of Health and Human Services, for guidance as they take their first steps toward reducing the possibility for environmental hazard in the project, whichever way it goes.

Who pays?

The DNR Fisheries Division likes the idea of getting rid of dams on the Kalamazoo River because dams obstruct natural movement of fish.

But 50-60 homeowners with property along the current impoundment would see their landscapes drastically changed if the millpond was gone, and instead the river ran its natural course. The millpond is currently used for kayaking and fishing, Rice said. The impact of that change is one of the costs that will need to be weighed.

Who bears the financial cost of the work is a consideration as well.

Other dams on the stretch of river from Kalamazoo downstream are part of a federal Superfund cleanup site, so the process for cleaning up the contaminated sediments -- in those cases, polychlorinated biphenyls, PCBs, from the paper industry -- is paid for in part by the paper companies potentially responsible for creating the problem.

The Plainwell dams farther downstream on the Kalamazoo River have been removed, the Otsego Township dam is in the process of being removed, and the Trowbridge and Otsego dams are slated for eventual removal.

In the case of the Marshall Dam, the legacy contamination in the sediments behind it could be 100 years old, Trumble said, and the process of determining where they originated would take a long time.

Although the city is not required to clean up sediments where they have settled, if Marshall wants to repair or remove its dam, the city would be on the hook for the cost of preventing contamination from moving downstream, Trumble said.

What next?

City officials promised to keep the people of Marshall informed about any and all dam related information.

Rice said after the various cost estimates are made, public forums will be scheduled in early 2017 to seek public input on the options.

Meanwhile, a complete copy of the city's sediment sampling can be obtained free of charge on the city's website, along with other project related information.

Click here for more information.