Sunday, October 05, 2014

Next steps Shiatown Dam Removal

Shiatown Dam Removal
Project Next Steps
By Graham Sturgeon, staff writer

PLANNING – Stakeholder panel met Wednesday, Sept. 24, to
discuss planning for the ongoing removal of the Shiatown Dam on the
Shiawassee River just upstream of the Bennington Road bridge.
They included the Shiawassee Township Supervisor (STS), members
of the Michigan Department of Natural Resources (MDNR) and
members of the Friends of the Shiawassee River (FOSR).
Phil Hathaway (FOSR),
Kevin Smith (FOSR),
Chris Freiberger (MDNR),
Joe Leonardi (MDNR),
Anthony Karhoff (STS)
Gary Burk (FOSR)
Tom Cook (FOSR)

An update on the continuing removal of the Shiatown
Dam, on the Shiawassee River just upstream of
the Bennington Road bridge, was Wednesday night
by the Friends of the Shiawassee River (FOSR) at the
Shiawassee Township Hall in Bancroft. Members of the
Michigan Department of Natural Resources (MDNR)
and Shiawassee Township officials heard engineering
consultant Scott Dierks’ three-phased plan to gradually
remove what has been termed the dangerous and outdated
dam from the Shiawassee River, and to restore the
river’s flow and functionality.

The process began two years ago with the impoundment
drawdown and this group is planning the next two phases
of the plan, set throughout 2015. Partial dam removal began
in the fall of 2012 after a 12-year-old girl drowned
at the dam in May of that year. The next phase of the
removal calls for the elimination of the piers, retaining
walls and the powerhouse, along with filling in of the approximately
12-foot-deep scour hole just downstream of
the dam, using the concrete rubble created by demolition
of the structure.

Phase III will include channel restoration, stabilization
and habitat improvements. The group hopes to create a
safe atmosphere that can be enjoyed by the community,
and to create a viable aquatic habitat for the river’s wildlife
and vegetation.

The FOSR has sought and received a number of grants;
organizing those plans will aid the group in obtaining future
grants. They have already received a $162,700 grant
from the MDNR, and a $62,500 grant from the Saginaw
Bay Watershed Initiative Network (SBWIN). Both of
these grants were earmarked for Phase II of the project,
and the group has applied for several other grants that will
aid in the restoration of the river, including a $30,000 Fish
and Wildlife grant. The group plans to create bid documents
by the start of the year, with construction beginning
by mid-summer.

The plan for now appears to involve a gradual removal
of the existing structure, as the group wants to retain the
sediments that have accumulated on the upstream side
of the dam to maintain the river’s shape and integrity.
Removing the dam all at once would have the effect of
widening and deepening the river due to the immediate
loss of most of the collected sediment. For this reason,
the dam’s skirting will initially be left in its place to promote
a gradual dispersal of the sediment in question. The
gradual removal option should have the effect of lowering
the floodplain, therefore reducing the risk of flooding for
those in the river’s contiguous vicinity.

After the panel concluded their demonstration they then
opened the floor to the audience for questioning. Some
of the better questions asked were concerning the matter
of flood insurance and the issue of the dreaded sea lampreys.
A local resident asked if those living in the floodplain
would see a decrease in their flood insurance if the
floodplain were lowered, to which FOSR member Gary
Burk replied that he was not sure.
“If anything it will reduce flood risks downstream
because there will not be the threat of dam failures,”
Burk said. “We have already taken flood risks out of the
equation upstream by controlling the flow of water into
the dam.”

On the issue of sea lamprey, MDNR representative Joe
Leonardi dispelled the fear of an infestation should the
dam be removed. “As it is currently, the dam is not a barrier
that is keeping the sea lamprey out. But there is not
as large of a population as people would think.” He also
noted that the state plans to use TFM, or 3-triflouromenthyl-
4-nitrophenol, to treat the entire river to eliminate
the dangerous aquatic predator.

For more information, persons may check the Friends of
the Shiawassee River website,