An all ready delayed $7 million project intended to prevent the invasive sea lamprey from migrating further up into the Grand River and its tributaries has encountered another snag.
Harpersfield dam is part of Ashtabula County Metroparks’ 53-acre Harpersfield Covered Bridge Park. It is located off Route 534 and just south of I-90 in Ashtabula County’s Harpersfield Township. It is an enormously popular steelhead fishing spot and an upstream jumping off place for canoeists and kayakers.
And the dam serves as an effective barrier against supplemental upstream intrusion by sea lampreys. If the 117-year-old dam were to fail this action would allow the invasive species nearly 1,300 additional miles of main stem and tributary spawning grounds.
Thus a joint, local, state and federal project began to work on preventing the aged structure from experiencing a catastrophic failure. Project partners include the U.S. Army Corps of Engineers, U.S. Fish and Wildlife Service, The Great Lakes Fishery Commission, the Ohio Deaprtment of Natural Resources, the Ohio EPA, and the county parks system.
A moderately heavy rain event December 21st saw the dislodging of two expensive coffer dam bladders at the fabled Harpersfield dam. These bladders were installed in early November above the dam and its adjacent iconic covered bridge.
The two heavy-duty synthetic fabric multi-chambered water-inflatable devices – each costing upwards of $30,000 - were sent over the dam as a result of the rain-induced high water. One of the bladders became deflated and wrapped itself around a cover bridge support. Meanwhile, the other bladder scooted about 150 to 170 yards downstream where it came to rest in the middle of the Grand River, stuck on the stream bed.
A third coffer dam bladder remained in place above the dam and situated extending from near the north bank.
As a result of the two coffer dams’ departure, water began shooting out in a cavity of the dam that had been demolished along the stream’s north bank. The plume of water started eating away at the soft bank where it lips around a part of the structure that remains in place.
Project engineering firm Eclipse Company of Chagrin Falls immediately began establishing a temporary fix – a detail that included working through Christmas Day - dumping concrete dam remnants in the gaping maw; some of the material still eqipped with protruding strands of rebar steel.
By December 26th the breech largely was plugged though water still continued to stream through the cracks and crevices formed by the placement of the slabs of concrete and rock. A pair of earth-moving equipment were employed just downstream of the dam, scooping up more rock and wayward rebar-reinforced concrete plates in order to reinforce the enlarging hollow below the temporary stone dam edifice.
Officials with the U.S. Army Corps of Engineers, Eclipse and others met December 26th to discuss the best way to fix the problem, remove the two dislodged water-inflatable bladders and proceed with the anticipated two-year-long project that was to have begun in 2017.
This was the second delay for the project. However, a dispute over a privately owned 0.3-acre parcel on the south bank held up the affair, the county park district weary of going to court with an eminent domain claim, said an official with that agency.
This delay helped stall the project’s start, and also almost certainly became a contributing factor in its cost rising from an original price tag of about $6 million to close to $7 million, a Corps official said.
The Corps project manager for the site – Gabriel Schmidbauer – said his agency would have preferred that the bladders been anchored with the use of large rock or concrete blocks than by using rigging and driven posts. That was not the case, and the resulting loss of the two bladders and subsequent emergency response meant that the project is requiring revision “to ensure that this won’t happen again,” Schmidbauer said.
“There’s going to be close scrutiny with any plan by my team, and the placement of the bladders must be rock steady,” Schmidbauer said. “Any plan that comes about must be the right plan and executed properly.”
Schmidbauer says also the two dislodged bladders appear to be salvageable and if so, they will be moved back above the dam and reused. A key is to make certain this work is done safely for Eclipse crews sake as the Grand River’s current is tricky, especially when rain events or snow melt dumps large volumes of water into the stream, rising its level quickly and swiftly.
The same safety concern applies to any loosened rock and chunks of rebar-fitted concrete that have made their way downstream. These pieces could prove hazardous to workers as well as anyone wading the stream or navigating it in paddle-sport vessels such as canoes and kayaks.
“Safety is our priority,” Schmidbauer says.
In that regard as well the Ashtabula County Engineer’s office made a visual inspection of the covered bridge. The county agency was said to have found that the dislodged bladder hung up on the bridge piling did not threaten the integrity of the structure.
“I’m not an engineer but that’s always a big concern,” said Larry Frimerman, the metroparks’ executive director. “And I want to stress to anglers to stay out of the river near the dam, especially since there could be debris still there.”
Schmidbauer did add that any additional cost resulting in the bladders dislodging, their possible removal and reuse, the building of the temporary dam patch, and other resulting extra project costs will likely be borne by Eclipse.
“We did tell Eclipse that it was their responsibility, but we do have some contingency money and I still expect that the project will be completed by late 2020 with possibly even some savings,” Schimbauer said.
- Jeffrey L. Frischkorn