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
JFrischk@Ameritech.net
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