IN ACTION
48
MAY-JUNE 2014
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&
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Breaking under water
R
emediation of the Cuyahoga River
in Ohio, USA, to return it to its
pre-industrial condition required
the removal of two dams across its flow.
RiverReach Construction, a specialist
in environmental stream and wetland
restoration, was brought in to remove the
structures. The first to go was the Sheraton
Mill dam, a 12 m (40 ft) long and 3 m (10ft)
high structure. However, access to this
dam was only possible from upstream so
RiverReach had to adopt an unusual approach.
A 4.8 tonne Komatsu PC45MR zero tail
swing excavator equipped with an Atlas
Copco SB 552 breaker was floated into place
on a modular barge and moored above the
dam and the breaker was then used to open
‘windows’ in the dam structure to allow the
water level behind the dam to fall. An Atlas
Copco XAS 185 compressor supplied a flow
of air to prevent the water from entering the
percussion mechanism of the breaker during
the work. Once the level had fallen sufficiently,
a 39 tonne Komatsu PC360 equipped with
an Atlas Copco HB 3100 breaker, again
supplied with air by the compressor, was used
to remove the rest of the dam structure. It
took just one day to complete the work. The
PC360 with the HB 3100 then moved on to
remove the second dam, the Lefever Dam,
a 27.4 m (90 ft) long and almost 4 m (13 ft)
high structure. This time access was possible
from the downstream riverbank, allowing
the PC360/HB 3100 combination to quickly
remove the structure.
Once demolition was complete, RiverReach
cleaned up accumulated debris and remnants
of the concrete and rebar. Concrete support
walls were then built to support the old
powerhouses to protect these historic
structures from variations in river flow and
the debris that comes down the river during
high water events.
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A Komatsu 4.8 tonne PC45MR teamed with an
Atlas Copco SB 552 breaker was used during
the initial demolition of the Sheraton Mill dam
on the Cuyahoga River
