Potagannissing River Dam

Photo of the Potagannissing River Dam before it was removedSituated on state-owned land on Drummond Island in northern Lake Huron, the Potagannissing Dam impoundment has been managed as a wildlife flooding for waterfowl for the past 60 years by the Michigan Department of Natural Resources.

Built in 1947, the dam, unintentionally, also blocked fish, northern pike in particular, from migrating upstream for spawning.

In an attempt to undo this circumstance, the DNR constructed a fish ladder at the dam in 1989 that they hoped would allow various game fishes to pass into the high-quality spawning and nursery habitat that existed in the vast shallow marshes upstream of the dam.

"Unfortunately, migrating pike from Lake Huron and the St. Marys River had a difficult time getting through the fish ladder or through the weir," said DNR Fisheries Biologist Tim Cwalinski.

The situation at the Potagannissing Dam impoundment remained unchanged until several years ago when DNR wildlife biologists, who manage the dam, became concerned that the aging structure would require substantial financial investment in the future in order to keep it functioning properly.

Photo of the dam during the removal projectTo address long-term operation and maintenance of the structure, DNR officials explored several options, ranging from the dam's complete removal to a complete overhaul.

In 2004, members of the Drummond Island Sportsman's Club (DISC) proposed a plan to increase passage of northern pike at the weir.

"Club members told us that northern pike abundance had declined in the entire St. Marys River system and Potagannissing Bay in recent years," Cwalinski said, "and this was confirmed by the catch of pike during our own surveys of the river system over the past decade."

DNR fisheries biologists concurred with the primary goal of the proposal and but wanted to further examine two additional elements at the site: removal of the non-functioning fish ladder and partial removal of the dam headwall.

In their ongoing discussions with DISC, DNR personnel proposed a compromise that would best address the various biological, social and economic factors -- the three pillars of the DNR's holistic approach to ecosystem management.

The DNR's plan called for removing three feet from the top of the dam and then building a series of four rock-ramp fishways at the site to reduce the slope and provide resting areas for non-leaping fishes.

The project would reconnect upstream and downstream habitat for improvement of the wild spawning pike population that sustains a popular fishery in the area but also would provide passage for all fish species.

"Although the club members' main interest was the northern pike, they eventually were receptive to the plan designed by Chris Freiburger that would provide passage for all fish species over the dam," Cwalinski said. "This was a major change from the original proposal, but both groups worked through the issues to an agreement."

Photo of the headwall being removedFreiburger is the supervisor of the DNR's FERC program, which oversees the licensing of hydropower plants throughout the state that fall under the jurisdiction of the Federal Energy Regulatory Commission (FERC).

He said the project planning began in 2005 and moved very quickly to implementation largely because of the local sportsman's club's dedication and commitment of resources.

All labor and equipment to the project were donated by DISC, while DNR fisheries biologists provided onsite supervision. Dam modifications were completed in September 2006.

"The efforts of DISC allowed the department to complete this project within a limited time and under difficult budget constraints," Freiburger said.

The project costs were close to $50,000; with nearly half of that provided by DISC. Photo after the dam was removed Additional financial assistance was provided by the U.S. Fish and Wildlife Service's National Fish Passage Program.

Cwalinski said the project will help to improve the status of the northern pike as an important game fish in the lower St. Marys River and Potagannissing Bay.

But he cautioned that it will take some time to rebuild stocks.

"Good habitat is the key to producing northern pike," Cwalinski said, "but ensuring that these fish and other species now have access to the high-quality spawning and rearing areas that exist upstream of this dam is a good beginning."

In addition to this project, DISC is an active collaborator in other efforts in this part of the state. Members operate a walleye rearing pond to help the DNR achieve stocking targets and assist the federal government with the control of double-crested cormorants in the area, as well as continuing to maintain the Potagannissing River Dam site.

"Working with DISC exemplifies the notion that agencies and local groups can work together in harmony to improve the aquatic resources of the state of Michigan," Cwalinski said. "More and more the DNR is seeking to build cooperative relationships with local constituents to protect and manage our natural resources."

Photo of the Potagannissing River Dam after it was removed and the final produce