Report: 52% of 138 dams are in fair or better condition
The majority of Oakland County’s regulated dams are in fair or better condition with only a small number showing signs of significant structural decline, according to a new report.
In July, the county board of commissioners’ requested that the county water resources commissioners office compile a report of the status of the county’s 138 dams following the breaking of the Sanford and Edenville dams in midMichigan, which caused historic flooding and displaced over 10,000 residents in May. The report is based on information obtained from the Michigan Department of Environment, Great Lakes, and Energy (EGLE), as well as field work undertaken by the WRC staff.
According to the report, 73 of Oakland County’s 92 regulated lake level dams (46 are unregulated) are characterized as being in fair or better condition. 32 of those regulated dams are owned, operated, and maintained by the WRC under Part 307 of the Natural Resources and Environmental Protection Act of 1994 with the others being privately (58) or publiclyowned (48).
“Even among those that did not meet this threshold, there were no structures identified that appear to pose an immediate or significant threat to the environment or to the downstream property owners,” read the report. “WRC staff will make the effort to follow up with owners of lake level control structures that need a current inspection and/or repairs and will
provide information to the State to update their database.”
Of the county’s 92 regulated dams reviewed for structural condition, six were found to have been in poor condition (Pettibone Pond Dam, Bevins Lake Dam, Vhay Lake Dam. Haven Hill Lake Dam, Holly Dam, and Erity Dam). The Fenton Dam in Rose Township was the only regulated dam in unsatisfactory condition.
Jim Nash, county water resources commissioner, said issues discovered with some the county’s dams are “inconsequential” based on the potential of what happened in mid-Michigan.
“Overall, we found that the dams in Oakland County are in pretty good shape,” he said. “The ones that have issues are not going to be very impactful from what I understand. Our county- owned dams are extremely well maintained.”
71 of the county’s 92 regu
lated dams are classified as a low hazard potential. The remaining 21 dams were given a significant (13) or high hazard classification (8) with each of them having an emergency action plan in place as required by EGLE. 17 of the 21 high and significant hazard dams were found to be in satisfactory condition.
According to the report, 16 of these high hazard dams are owned by a governmental agency, suggesting that most of these dams have a funding source for required repairs.
The other five dams are privately- owned. Of the county’s 92 regulated dams, 66 are publicly- owned (71.7%) while nearly 70% of the county’s unregulated dams are privately- owned. At least 55% of the county’s 138 dams are 50 years of age or older with at least 9% being over 100 years old.
Of the county’s 60 regulated dams not owned by WRC, 23 either had no inspection report on file with
EGLE (9) or were overdue for inspection (14). As a courtesy, WRC staff performed a visual inspection of these nine dams with at least three appearing to need significant repairs – Petrauskas Pond Dam, the Secord Lake Dam and the Lake Araho Dam.
Even though all nine dams are rated as low hazard potential, the county is recommending that all be inspected as soon as possible and be put on a regular inspection schedule. The other six regulated dams without inspection reports on file include: Spring Lake Dam, Renchik Dam, Lower Hatchery Dams, Tull Lake Dam, Troy Lake Estates Dam, and Pebble Creek Detention Basin Dam.
The WRC report focused on the following information for each of the documented dams: Number of control structures, EGLE ID, ownership, party responsible, hazard classification, condition rating, last inspection date, frequency of inspection, and emergency action plan.
For the review process, WRC staff utilized data from the EGLE geographical information system (GIS). This data set was then divided into three categories for review including:
• Regulated structures not owned by WRC: In total, there are 60 structures in this category. Nine structures in this category did not have inspection reports on file with EGLE, so WRC staff visited each one to inspect them in person.
• Regulated structures owned and maintained by WRC: In total, there are 32 structures in this category. Although all of these structures have inspection reports on file with EGLE, WRC staff reviewed the inspection reports for the purpose of compiling this new report.
• Unregulated or inventoried structures: In total, there are a total of 46 structures in this category. These structures do not have an inspection report on file with EGLE since they are not regulated and, therefore, are not required to submit inspection reports. WRC staff visited these dams in person to conduct high-level visual inspections.
In- depth inspections of the 32 county-owned dams are completed once every three years, but are visually observed on a regular basis by WRC staff. Costs to operate and maintain these dams are paid for by property owners located in special assessment districts.
In 2019, the total assessment for lake levels was $819,000.
The assessment fees vary from year-to-year based on the need for dam-related projects.