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Tributary to Little
Bennett Creek
Damascus, Maryland
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The Use of
Native Materials for River Restoration
in a Rural Watershed Project Constructed
Fall of 1999.
Sponsor
The project was funded by the
Montgomery County Department of Public
Works & Transportation.
Project Description
The existing channel was located in a
cattle pasture where grazing and hoof
impacts resulted in an extremely
degraded stream channel, which in turn
impaired existing wetlands and water
quality. A design was prepared to raise
the invert of the existing stream to
allow it to communicate with the
surrounding floodplain, and to create
and restore forested wetlands throughout
the surrounding floodplain areas.
Wetland sod along with river gravel and
cobble were used to stabilize the
restored channel. A diversity of bed
material sizes was imported to provide a
natural particle size distribution in
the restored channel. The design profile
included the creation of naturally
sloping riffles and pools to mimic the
profile undulations of a natural stream. |
Construction
The stream restoration portion of the
project was designed by Scott McGill,
and the wetland construction was
designed by Jim Morris, both principals
of Ecotone, Inc. Both project components
were constructed by C.D. Davis
Excavating.
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Cost
Costs associated with the stream
restoration component of the project
averaged $30.00 per linear foot of
stream restored. |
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Phases of
the Project |
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Stream Prior To
Construction. |
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Cattle pasture prior to
wetland construction project. This area
is now wetland cells 2 and 3. Photo
taken 1998. |
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Cattle which are allowed
access to the stream contribute to
problems. |
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Years of exposure to
grazing cattle have led to an ecosystem
in poor health. |
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The stream experienced
high bank erodibility as a result of
hoof impact. |
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A stable stream channel
was created by raising the invert of the
channel. |
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Once native sod is placed
along the banks the stream will be
complete. |
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A crossing was installed
so that cattle would have access to the
stream. |
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On site wetland sod was
placed along the stream banks. |
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Immediately Following
Stabilization. |
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The new channel is
stable; the sod mats provide good
initial bank stability. |
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The new channel several
days after construction is complete. |
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Soft brush was used
adjacent to the low flow channel to
provide deep rooting stability. |
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Cattle explore the new
stream crossing. |
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Looking upvalley in
October of 1999. Cell 5 is in
foreground. |
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Looking upvalley during
construction, October 1999. |
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Nine months post
construction vegetation is taking a
strong hold along the stream banks. |
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Eleven months post
construction lush vegetation makes it
hard to see the stream channel in this
photo. |
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The stream creeps its way
through the wetland plants. |
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Restored stream looking
upstream. |
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Wetland Cell number 5,
summer of 2001. |