Standish dam rehabilitation under consideration

TECUMSEH — The city of Tecumseh is looking to begin much-needed repair work to Standish Dam.

The Tecumseh City Council discussed a proposal from Walker-based Land and Resource Engineering (LRE) to evaluate and design the rehabilitation of the dam and associated spillway during a study session Sept. 21 prior to its regular meeting.

The dam and its associated spillway and earthen embankment received two inspections from the Michigan Department of Natural Resources (DNR) — the first time in 2013 and again in 2017 — that recommended the city rehabilitate the dam and spillway water control structures, according to a summary presented by city manager Dan Swallow.

The city applied to the DNR’s Dam Management Grant Program but was rejected, since the grant is mostly focused on dam removal.

Pursuing a grant from the Federal Emergency Management Agency would also be difficult since the dam is not a safety risk, since it is unlikely to cause property damage if it burst, like what happened earlier this year in Sanford and Midland.

With funding low due to the Great Recession, the structure continued to deteriorate. The city began setting aside funding for the project in its capital improvement program over the past few years. The funding set aside is not enough to pay for the entire rehabilitation, but enough to cover initial engineering analysis costs. For the project, the city could later look into financing options such as a capital improvement bond and potentially asking owners of property abutting the waterfront to participate in an assessment district, while the city continues to cover the majority of the costs.

With another state inspection approaching, city officials felt that it is time to look seriously at rehabilitating the dam and, through the recommendation from the Lenawee County Drain Commission, contacted LRE to come up with a proposal for assessment, design and to bid out work on the project.

According to Swallow, Dan Fredricks, vice president of LRE, visited the dam and spillway with DNR dam management staff and reviewed historical drawings and structures to prepare a proposal for the city.

The proposal brought to the city council estimated the cost of the evaluation, design and bidding out process for rehabilitation to be $64,740. Swallow wrote that this is more than expected, but it is based on good understanding of what will be required and will result in a well thought out analysis and design.

One example is the firm’s recommendation to eliminate the dam’s concrete spillway along the dam’s raceway, rather than rehabilitate it. This would cut down on the the cost of rehabilitation without compromising the function and safety of the system.

“If the engineering analysis holds true, this would be a long term savings cost savings for the City and one less structure to maintain,” Swallow wrote. “It is also likely less expensive to eliminate the spillway, versus rehabilitate the structure as part of the initial construction project.”

Fredricks presented LRE’s proposal at Monday’s study session through video conference, describing the processes in LRE’s proposal, which includes getting federal and state authorization and permits.

“Basically what we're seeing is more cracking in the concrete, particularly in that spillway structure. And then he mentions that the H-pillars, those are the steel pillars that help support the dam structure as well as the catwalk, those are continuing to rust,” Swallow said, describing the deterioration at the dam. “And so they've been repaired a few times already where we've welded in steel plate to help repair them. … Probably at this point, the whole pillars need to be replaced because they've been repaired too many times.”

The dam is not in as bad condition as the concrete spillway, which is only reachable by foot, and repairing it would be very difficult.

Removing the spillway, according to Fredricks would cause only negligible rise in water levels only during the worst rainfall.

Rising water levels were not a concern for residents who live along the raceway who attended the meeting. During drought conditions, the raceway is too dry.

“My concern is the water level going down. It’s not going up. You get to the point where I don’t have any water behind my house at all. … I’ve lived there 33 years and all of a sudden i don't have any water,” one resident said. “And another thing is in the summer when it's hot and humid, there ain't no water back there, the muck smells.”

The residents described the beauty of living on the raceway, which the city said it aims to preserve by rehabilitating the dam.

“I think that's the No. 1 priority. (Making) sure those dams are safe. We’ve seen what happened up in the middle of the state a few months ago and we do not want that to happen here,” Mayor Jack Baker said. “At the same time, we would like to hopefully help out the residents who live on that raceway to be able to have enough water to be able to look and feel good about it and not having to look at a swamp, but rather look at a nice, watery area that they can draw from to water their yards and things like that.”

The city council expects to vote to approve or reject a contract with LRE for evaluation and project design at its Oct. 5 meeting.