Goodrich-For the past 100 years the Goodrich dam at Hegel Road has successfully held back the Kearsley Creek, creating a 240-acre mill pond.
However, a series of reports indicate the dam and pond could be jeopardized.
The future of the century-old structure was the subject of debate on Jan. 30 during a special meeting at the village offices.
Engineers from WadeTrim and Stantec prepared a proposal, at the village council’s request, to provide an engineering evaluation and feasibility study to explore alternatives for modifying the current structure, which needs extensive repairs.
According to the Michigan Department of Environmental Quality Dam Safety Inspection Report issued in April 2012 that evaluated the structural condition and hydraulic capacity, the dam is currently in fair condition, although a number of remedial actions were outlined. The 15-foot high head dam is an at-risk dam, rated by the MDEQ as a significant hazard potential dam that could cause catastrophic damage if it were to fail. Both recent and past inspections of the dam show voids in the dam’s embankments indicating groundwater seepage around the dam which ultimately can lead to structural failure of the dam over time.
‘The report will help answer questions and produce a long range plan,? said Jakki Sidge, village administrator. ‘Right now two of the five gates in the dam don’t open to let water go out. We have been babying the dam along forever. We need to make sure the dam is safe.?
The initial report from WadeTrim and project partner Stantec included engineering evaluation of the existing dam, design alternatives, hydrology and hydraulics, estimated the project cost to be about $100,000. However, the council will now only consider less extensive repairs of the dam. The scope of the upcoming project, which village officials say is due to the MDEQ by May 2013, will include only the engineering evaluation and hydrology and hydraulics study and cost about $50,000.
Jason Kenyon, vice-president of WadeTrim who made the presentation last month, said a few ideas will be presented to the public to deliberate.
‘The next step will be to help the village respond to the MDEQ,? he said. ‘A scaled down version of the project will be discussed on Monday night.?
While evaluations of the dam and mill pond will be ongoing, no report has been issued to determine the extent of the damage potential if the dam were to break, added Kenyon.
‘The Atlas Country Club (golf course) has reported floods,? he said. ‘Regarding a liability perspective’it’s not for me to answer.?
While dams often differ in size, water volume and structure characteristics, they can breach.
Such was the case in northern Michigan this past fall. According to the Traverse City Record Eagle, on Oct. 6, 2012 an assistant director of Traverse City’s Department of Public Services called 9-1-1 dispatchers to report that a pond was dumping its contents into the Boardman River during construction on the Brown Bridge Dam. The resulting flooding raised the river 5 feet and caused damage to at least 53 properties downstream. The breach occurred as Molon Excavating and an engineering firm, AMEC, worked to remove the dam ? part of a long-term project to remove three Boardman River dams.
An investigation into what caused the pond to release into the river appears focused on the failure of a dewatering structure built adjacent to the dam. The structure was supposed to slowly release water into the river over a period of weeks. Instead, the pond breached the structure and raced into the river in a matter of hours.