With Shaker council approval pending, the quick fix is in at Horseshoe Lake dam - cleveland.com

SHAKER HEIGHTS, Ohio -- A temporary fix on the failing dam and spillway at Horseshoe Lake could take about six weeks to complete, easing flooding concerns downstream during as much as a 100-year rainfall event.

City Council set a special meeting Tuesday night (Oct. 12) to approve the $429,250 contract -- to be reimbursed by the Northeast Ohio Regional Sewer District (NEORSD) -- for the “Interim Risk Reduction Plan.”

The repair features a controlled breach that would channel rising stormwater out of the already-drained lake.

This would eliminate most of the potential for water “overtopping” the toughly 170-year-old earth-and-stone dam, classified by the Ohio Department of Natural Resources as “Class 1.” That means the dam’s failure would result in the loss of life and property.

After heavy rains over the July 17 weekend, the city’s dam tender noticed “additional movement of the spillway structure, a new condition that was a cause for concern, since the city had previously made two repairs, lowering the lake’s water elevation approximately 6 feet,” City Public Works Director Patti Speese noted in an Oct. 8 memo to council.

At the same time, NEORSD officials had already recommended back in June that the dam -- and subsequently Horseshoe Lake itself -- be removed and that two branches of Doan Brook be restored to their earlier natural state. The sewer district would also bear the projected $14.7 million cost there.

But that project could take several years, prompting the city to hire AECOM Technical Services in mid-August to come up with a stopgap measure that cost about $50,000 to design.

Troy Naperala, vice president for AECOM’s Water Resources Division, planned a powerpoint presentation for council on Tuesday to show what was uncovered with further core drilling and partial removal of the walkway on the dam’s stone observation deck, where a nearly 7-foot void was discovered and filled.

That’s in addition to the controlled breach’s partial removal of the stone-and-earth dam to the south of the spillway and observation deck.

As the powerpoint states, “The solution is to eliminate overtopping during frequent events through construction of a temporary, open-channel, rock-lined spillway.”

From there, AECOM further recommended shoring up the tunnel that conveys the flow from the lake to Doan Brook with “sliplining” 20-inch flexible plastic pipe and grout, mitigating the risk of erosion and further voids.

The plans also call for 6,000 cubic yards of excavation, 300 cubic yards of concrete or grout and 2,320 tons of riprap stone reinforcement, about two-thirds of that being reclaimed from onsite sources.

Speese said the best and lowest bid for the work came from Akron Building and Outdoor Maintenance Inc., doing business as River Reach Construction. Three other bids ranged from $439,000 to $702,000.

“Given the gravity of the conditions at Horseshoe Lake, Public Works requests authorization to enter into an emergency contract so we can proceed with the much-needed project without delay,” Speese said, noting that “River Reach understands time is of the essence and is able to start the project as soon as the contract is fully executed.”

Speese added that she will return to council with an agreement from NEORSD to put the money back into the city’s Sewer Fund.

A link to tonight’s meeting can be found here or at https://www.shakeronline.com/AgendaCenter/ViewFile/Agenda/_10122021-722

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With Shaker council approval pending, the quick fix is in at Horseshoe Lake dam - cleveland.com
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