Called the Frankenmuth Fish Passage Project at the Cass River Dam, the project has been in the making for over 13 years. Watching it finally in construction has been mesmerizing, amazing and inspiring! Frankenmuth’s Dam project will be one awesome sight when it is done. It’s already having an impact now and will for the next few hundred years, so it’s certainly worth all the dam effort it took to get it here.

Constructed before the Civil War, the Cass River Dam has been a community workhorse and landmark for more than 160 years.

Now part of the river system itself, the dam structure supports the south bank of the River, as well as providing the needed water depth upstream supporting local commercial boating and maintaining the river profile as we see today. Forecasting a minimum investment of $350,000 to repair the dam for the short term back in 2002, the City looked for an alternative to make its investment go farther.

Before you read much further, you should know a little bit about the Cass River. The Cass River is part of the Saginaw Bay Watershed, Michigan’s largest watershed and America’s largest freshwater coastal wetland system. With all or part of 22 counties, the area is home to 1.4 million people and includes diverse industries and is an agricultural center. It provides habitat for large populations of waterfowl, birds and more than 90 fish species. Of course, the area is also home to Frankenmuth, Michigan’s Little Bavaria!

Where once the Saginaw Bay was teaming with millions of walleye and lake sturgeon, by the 1960’s and 70’s, the great fishery was nearly lost. As it turns out, dams, like the one in Frankenmuth, are a contributing factor to the loss of habitat for fish reproduction. However, continual improvements have helped the Saginaw Bay repopulate its fishery and this project is a good example of that ongoing work. Efforts to support natural fish reproduction – such as restoring fish passage – rebuilds the Saginaw Bay and Lake Huron fishery. This project enables sustainability by taking away obstacles and allowing for a natural cycle. That would be a very good thing.

Understanding the desirability of creating a fish passage at our dam and wanting to keep the river profile as is, we looked for an opportunity to explore new recreational options for the Cass River. With tourism the bread and butter for Frankenmuth’s economy, we sought a solution good for the environment and for tourism. An emerging tourism product – eco-tourism is defined as responsible travel to a natural environment. Eco-tourism is an excellent complement to the natural resource for eco-tourists bring in only what they need and leave only footprints! Eco-tourism activities such as fishing, bird watching, kayaking, and other river recreation round out our well-developed lodging, retail and restaurant offerings.

With a dam in need of repair, fish wanting to swim up stream and a town ready to host a new kind of tourism – we had the right blend of motivation to make the project happen.

The fish passage project is a constructed rapids, also known as a rock ramp. As its name implies, a 300-foot long ramp uses rocks in a wedge-like shape downstream of the dam to imitate a natural rapids. A series of 14 weirs or arches spaced about 20 feet apart, form the ramp. The existing dam will remain in place, covered in rock, maintaining water depth upstream of the dam supporting local commercial boating.

Fish can move through the weirs in both low and high water conditions, accommodating more diverse fish species. Once they reach the peak of the wedge (or the dam which is no longer visible,) fish swim over and off to find the love of their life and have many little fishes. Once the little ones are born upstream, they are imprinted with God’s magic GPS system, and return to spawn (or reproduce) during their life cycles. While the constructed rapids is man-made, the opportunity to imitate nature will create a sustainable system for the fish, helping to rebuild the Saginaw Bay Fishery.

The project is built of a variety of stone sizes, with a total stone weight of about 25,000 ton or 49,000,000 pounds. The large stones are limestone from quarries in Alpena, Michigan. The smaller stones are primarily from Bay Port, Michigan. Surely, you now know why “Frankenmuth Rocks.”

Construction of the project will continue actively until mid-August 2015 with most of the downstream work completed by then. Work upstream and on the dam itself will proceed after Labor Day, when the water levels will be lowered. Once work is completed, water levels will return to current levels. All construction schedules are weather-dependent. The City’s contractor is planning to be fully completed by the end of September 2015.

The City had very specific reasons for doing this project. As a community and region, we will benefit economically and environmentally. But, in the end, the presence of a healthy fishery means the presence of good water. This is good for all of us living and working in the Saginaw Bay Watershed.

If you want to know more about the project, visit

Our guest blogger is Sheila Stamiris, Former Director of the Frankenmuth Downtown Development Authority. She has been around to see the dam project come to fruition and has great knowledge about the development of Frankenmuth in general.

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