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BRASSTOWN CREEK WATERSHED
RESTORATION
MONITORING REPORT,
EVALUATION & ACTION PLAN
JANUARY 2008
EXECUTIVE SUMMARY
Between 1999
and 2004, the Hiwassee River Watershed Coalition (HRWC) used funds
granted by the North Carolina Clean Water Management Trust Fund to
restore more than 30,000 linear feet (approximately 5.7 miles) of stream
in the Brasstown Creek watershed. Restoration work was conducted on 14
separate stream reaches. Each project involved extensive planting of
native vegetation in 30 to 50-foot wide strips along stream banks, and a
total of 121 in-stream structures were built to reduce erosion and
improve the geomorphology of the stream.
HRWC was
granted additional funds in 2004 to monitor and evaluate its restoration
work in the Brasstown Creek watershed over a 2-3 year period. Staff and
students of the North Carolina State University (NCSU), Department of
Biological and Agricultural Engineering conducted comprehensive
monitoring at 10 of the 14 individual restoration sites. Monitored
projects included four sites on Brasstown Creek, four on Little
Brasstown Creek, and two on smaller tributaries to Brasstown Creek. They
represent a wide range of drainage sizes and channel types and range
from recently constructed to seven years old. Additionally, they
represent the work of several different design teams and construction
contractors. Each project was monitored with regard to channel
stability, riparian vegetation, macroinvertebrate populations, and
suspended sediment.
Restoration
efforts at nine of the monitored locations have been highly successful
in terms of improving habitat, re-vegetating the riparian area and
improving the physical condition of the stream channel. Most banks are
now stabilized and erosion has been greatly reduced. In-stream
structures installed during restoration work have held up well and
maintained their intended function throughout the monitoring period.
Planted and naturally recruited vegetation is thriving and
macroinvertebrate populations appear to be stable. The substrate
throughout most of the reaches improved over time, providing better
habitat for both invertebrate and vertebrate life.
One restored
site was not as successful in terms of improving stream conditions; this
area provides lessons for future restoration projects. While all other
sites contained structures made of rock, this site utilized log
structures and nearly all of them failed. Bank erosion continues to be
a problem and negatively affects the macroinvertebrate populations in
that reach, but conditions have improved since restoration was
conducted.
Restoration
efforts in the Brasstown Creek watershed resulted in many improvements
in terms of both the biological and physical health of the watershed.
All of the sites require ongoing observation to ensure that the efforts
made to restore the watershed continue to improve water quality. There
is still work to be done at each of the sites, including removing
invasive species, planting some remaining bare areas, and continuing to
monitor both biological and physical parameters of stream health. |
