City of Sturgis electric department received a formal extension of time for the drawdown of its dam on the St. Joseph River near Covered Bridge in Centreville.
The drawdown of the reservoir area of the river upstream of the dam must be completed by Sept. 15, with anticipated start date of Sept. 8. Previously, the process was expected to begin July 6, with completion deadline July 15.
According to city manager Andrew Kuk, the drawdown project is in response to Federal Energy Regulatory Commission’s recent evaluation of conditions of the left embankment of the dam.
Conditions related to the left embankment have been noted and monitored for several years as part of the city’s continued am safety reporting through FERC, but as of May 5, FERC requested the drawdown as an “interim reduce risk measure.”
The drawdown required is three feet and is expected to affect the river by lowering water levels in an area from the dam about five miles upstream, just east of Mendon.
Following a request for extension, FERC completed an additional inspection and determined that, based on that review and some continued and additional monitoring measures, an extension could be granted.
At an informational meeting held in June, Chris Jeter, a lead engineer with Lawson Fisher Associates, said the embankment has had issues since 2016, when emergency grouting was done to address seepage concerns. That type of condition still exists through the earthen embankment.
Jeter said a preliminary engineering report was developed in 2021 to identify ways to flatten the slope and address seepage. An initial plan was submitted in 2022, then finalized in 2023. But Jeter and Chris McArthur, electric department superintendent for the city of Sturgis, said that design was not approved by FERC. So the city had to conduct analysis session with FERC to refine the design.
The city of Sturgis monitors the dam on a daily basis to ensure that it is operating properly and that there are no conditions that would result in failure of the embankment, according to officials. The city also monitors specific wells that are within the earthen embankment every few weeks to ensure the water surface within the area is not showing a trend indicating an issue.
You say nothing about how long Drawdown. Till 2027 that is what was said at the meeting