20180765 Ver 2_Year 2 Monitoring Report_20201124

Staff Review
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20180765
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Reviewer List:* Kaylie Yankura:eads\kyankura
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Project Information
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Project Name: High Hampton Golf Resort, LLC Holes 7 and 8 Culvert Removal and Restoration
Site
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918_Monitoring_Report_MY2.pdf 5.09MB
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This Year 2 Monitoring (MY2) Report is being submitted in order to satisfy the conditions of the NWP 27 (SAW
2017-02281) issued on April 25, 2019 and DWR 401 Water Quality Certification (DWR# 18-0765-V2) issued
on March 22, 2019.
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W By checking the box and signing box below, I certify that:
■ I, the project proponent, hereby certifies that all information contained herein is true, accurate, and complete to
the best of my knowledge and belief.
■ I, the project proponent, hereby requests that the certifying authority review and take action on this CWA 401
certification request within the applicable reasonable period of time.
■ I agree that submission of this online form is a "transaction" subject to Chapter 66, Article 40 of the NC General
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Submittal Date: Is filled in autorratically.

CiLearWater
C1earWater Environmental Consultants, Inc.
www cwenv corn
November 24, 2020
Mr. David Brown
US Army Corps of Engineers
Asheville Regulatory Field Office
151 Patton Avenue, Room 208
Asheville, North Carolina 28801
Ms. Kaylie Yankura
NC Division of Water Resources
2090 US Highway 70
Swannanoa, North Carolina 28778
RE: High Hampton Golf Resort, LLC Holes 7 and 8
Culvert Removal and Stream Restoration Site
Annual Monitoring Report — MY2
Henderson County, North Carolina
USACE Action ID No. SAW 2017-02281
DWR Project No.18-0765-V2
Dear Mr. Brown and Ms. Yankura,
High Hampton Resort, LLC received after -the -fact authorization for 880 if of stream impacts
associated with removal of a culvert and stream restoration activities at a tract of land (PIN 7571-
96-2363) known as the High Hampton Resort at 1525 NC Highway 107 South in Cashiers,
Jackson County, North Carolina. This Year 2 Monitoring (MY2) Report is being submitted in
order to satisfy the conditions of the NWP 27 (SAW 2017-02281) issued on April 25, 2019 and
DWR 401 Water Quality Certification (DWR# 18-0765-V2) issued on March 22, 2019.
Please do not hesitate to contact me at 828-698-9800 if you have any questions or comments.
Sincerely,
F`
Alea K. Tuttle, P.W.S.
Biologist
32 Clayton Street
Asheville, NC 28801.
828-698-9800 Tel
IRe'Clement Riddle, P.W.S.
Principal

High Hampton Golf Resort, LLC Golf Course
Holes 7 and 8 Culvert Removal and Stream Restoration Site
Annual Monitoring Report
Monitoring Year 2 of 3
USACE Action ID No. SAW 2017-02281
N.C. DWR Project No. 18-0765-V2
November 2020
Prepared By:
CLearWaLer
32 Clayton Street
Asheville, North Carolina 28801

Table of Contents
1.0 PROJECT SUMMARY..........................................................................................1
2.0 METHODS.............................................................................................................. 2
3.0 GEOMORPHIC MONITORING RESULTS ...................................................... 2
4.0 VISUAL MONITORING RESULTS.................................................................... 9
5.0 MONITORING SUMMARY...............................................................................11
6.0 REFERENCES......................................................................................................11
Monitoring Data
Figures
Geomorphic Assessment:
Table 1: Cross -Section Dimensions- Low Bank Stage
Table 2: Cross -Section Dimensions- "Bankfull" Stage
Cross -Sections 1-4 Photographs and Survey Plots
Visual Assessment:
Photographic Reference Photos (Photo Points 1-5)
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Attachment A:
Vicinity Map
USGS Topographic Map
Watershed Aerial Photograph
USDA Soils Map
Monitoring Features Map
Memo from Andrew Bick, PE, Headwaters Engineering
to David Brown, USACE and Kevin Mitchell, NCDWR
RE: Stability Assessment and Stream Enhancements UTs to Fowler Creek
High Hampton Resort, Cashiers, Jackson County, NC

1.0 PROJECT SUMMARY
High Hampton Resort, LLC received after -the -fact authorization for 880 if of stream
impacts associated with removal of a culvert and stream restoration activities at a tract of
land (PIN 7571-96-2363) known as the High Hampton Resort at 1525 NC Highway 107
South in Cashiers, Jackson County, North Carolina. This Year 2 Monitoring (MY2) Report
is being submitted in order to satisfy the conditions of the NWP 27 (SAW 2017-02281)
issued on April 25, 2019 and DWR 401 Water Quality Certification (DWR# 18-0765-V2)
issued on March 22, 2019.
Approximately 880 linear feet (LF) of culvert was removed from an unnamed tributary to
Fowler Creek (referred to in the attached plans as UT1) at the High Hampton Resort golf
course, which is currently undergoing a renovation. The banks of the daylighted channel
were sloped and large stone was placed in the bed and on the banks. Fowler Creek is in the
Savannah River basin (HUC 03060102). The site is located in Jackson County, North
Carolina and is accessed from Route 107, just to the south of the town of Cashiers. A site
vicinity map and USGS topographic map are included as Figures 1 and 2. An As -Built
survey documenting baseline conditions was completed on February 25, 2019, and
summarized in a memo to the USACE and NCDWR in a memo dated March 5, 2019 from
Andrew Bick, PE of Headwaters Engineering (Attachment A). Monitoring Year 1 efforts
were conducted on November 14, 2019. Monitoring Year 2 efforts were conducted on
October 26, 2019.
A digitized watershed boundary of the drainage area at the end of the 700 ft monitoring
reach shows a drainage area of 14 acres (ac), or approximately 0.02 square miles (mil)
(Figure 3). USGS web -based hydrology tool StreamStats to estimates the drainage area of
UT1 to be 22 acres, or approximately 0.03 mil. The High Hampton project site is located
in the southern Blue Ridge physiographic province (NCGS 2004) in the Blue Ridge Belt
in the Dqd (quartz diorite to granodiorite) rock unit formation, dating to the Devonian
period (359-419 million years ago) (NCGS 1985). Soils within the project area consist of
Udorthents and Edneyville-Chestnut Complex (USDA Web Soil Survey, Figure 4).
The performance of the project will be evaluated for geomorphic and
visual components. The following are specific performance standards:
• Geomorphic Stability — Channel dimension, and profile, remains within the range
of natural variability.
• Visual Assessment — Minimal bed or bank erosion/scour from natural channel
adjustment.
High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 1 of 11

2.0 METHODS
Clearwater Environmental Consultants (CEC) conducted geomorphic monitoring and
visual documentation of a 700 LF reach UT1 to Fowler Creek (hereafter referred to as
UT I) as shown in the Project Vicinity Map (Figure 1). Geomorphic monitoring of stream
dimension included a survey of four (4) stream cross -sections. The cross-section surveys
are located as indicated on the Monitoring Features Map (Figure 5), with three
representative "riffle" cross sections (XS1-3) and one representative "run" cross-section
(XS4). The cross -sections were monumented with permanent capped rebar pins and a
wooden stake on each bank to serve as a spatially referenced control. The cross-section
surveys were performed using a laser -level, reel tape, and stadia rod. Photographs of each
cross section facing downstream were taken on the day of monitoring. The locations of
these control pins were recorded with a sub -meter accuracy Global Positioning System
(GPS) device. Geomorphic data was analyzed using the Reference Reach Spreadsheet for
Channel Survey Data Management Version 4.2L. (Dan Mecklenburg, Ohio Department of
Natural Resources).
Photographic reference points (photo -points) were used to visually document stream
conditions and include both a downstream facing photo and an upstream facing photo at
each photo reference point. Photo -points were established at five (5) stations along the
length of the 700 ft UT1 reach. The photo -points were recorded with a sub -meter accuracy
GPS and monumented with a wooden stake. The photographer will make a reasonable
attempt to capture the same perspective in each photo -point location annually. Please refer
to Figure 2 for the proposed locations of all monitoring features.
The bankfull stage was determined using the North Carolina Mountain Regional Curve
(Harmon et al. 2000). Using a drainage area of 0.03 mil, the regional curve predicts
bankfull cross -sectional area at approximately 2.0 square feet (ft2) with a bankfull
discharge of 7 cubic feet per second (cfs), mean depth of 0.4 ft and bankfull width of 5.2
ft. Regional curve prediction at the extremely low end of the range of data for streams, as
in this case, is not as reliable as predictions for those in the middle of the range (between
2-30 mi2). Local streams with similar watershed size under reference conditions serve as a
better comparison in this lower range.
3.0 GEOMORPHIC MONITORING RESULTS
Based on the comparison to a local reference reach and regional curve data, it appears that
the daylighted channel was constructed with low bank heights and channel widths
exceeding the corresponding theoretical bankfull stage predicted by the North Carolina
Mountain Regional Curve. Therefore, floodwaters from the majority of rain events are
expected to remain contained by the channel. Geomorphic monitoring results are analyzed
below at the low bank stage (Table 1) as well as at bankfull stage estimated based on
regional curve data (Table 2).
High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 2 of 11

Low Bank Height
Due to the 0.03 mil contributing area of the watershed, flood events reaching the
low bank stage should be infrequent and exceptional.
Analysis of the MY2 surveyed riffle cross -sections corresponding to the low bank
height indicates an average cross -sectional area of 21.8 ft2 average width of 13.3 ft
and average mean depth of 1.6 ft. Cross section XS4 is a run located in a flatter
section of the reach with a slope of approximately 0.5% slope. Using corresponding
riffle facet slopes and an estimate of flow resistance coefficient of 0.05, average
discharge rate was estimated to be 261.9 cfs at low bank stage. Shear stresses in the
riffles at low bank stage were calculated to be approximately 8.4 pounds per square
foot (psf) on average. With reference to Shield's equation, the predicted grain size
for threshold of motion (stream competence) was 414.6 mm, or roughly 16.3
inches, at the low bank stage. This corresponds to the "small boulder" particle size
which could be mobilized at the low bank stage.
Table 1. Cross -Section Dimensions with parameters calculated at low bank stage
Units
Parameter
Riffle
Run
XS1
XS2
XS3
XS4
MY1
MY2
MY1
MY2
MY1
MY2
MY1
MY2
ft2
Cross Sectional Area
17.5
16.4
35.9
35.2
13.9
13.8
28.0
26.8
ft
Width
12.7
12.5
16.9
17.5
8.9
10.0
12.8
12.8
ft
Mean Depth
1.4
1.3
2.1
2.0
1.6
1.4
2.2
2.1
ft
Max depth
1.8
1.7
2.9
2.9
2.2
2.2
3.0
2.9
ft/s
velocity
11.1
10.6
14.4
13.4
11.3
10.3
3.1
2.9
cfs
discharge rate
195.3
173.1
516.8
470.5
156.4
142.1
86.0
76.9
Ibs/ft2
shear stress
8.1
7.5
11.9
10.7
8.2
7.1
0.6
0.5
mm
threshold grain size
399.0
1 369.5
584.2
1 523.6
401.4
1 350.5
27.0
24.4
facet sloe
15%
15%
13%
2%
channel sloe
6.2%
High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 3 of 11

Bankfull Stage
Using the hydrologic definition of "bankfull stage," flood events reaching the
bankfull stage should happen with relative frequency, with a recurrence interval of
approximately 1.5 years. The bankfull elevation was calculated based on a mean
depth of 0.4 ft predicted by the contributing watershed area of 0.03 mil. The
resulting bankfull elevations were below the observed low bank height, with bank
height ratios ranging from 3.4 to 4.4. The stream is considered moderately
entrenched, with entrenchment ratios ranging from 1.3-2.0.
Cross section dimensions corresponding to the bankfull stage resulted in average
cross -sectional area of 2.6 ff and average width of 7.7 ft. Using the estimated
bankfull stream dimensions, stream competence at this stage was calculated at
102.7 (approximately 4 inches) and appears to match the observed median grain
size. While quantitative analysis of streambed sediment size (i.e. Wolman pebble
count) was not performed, the observational estimate of average streambed particle
size is medium cobble, which ranges from 90-128 mm.
Table 2. Cross -Section
Dimensions with parameters set at bankfull stage
Units
Parameter
Riffle
Run
XS1
XS2
XS3
XS4
MY1
MY2
MY1
MY2
MY1
MY2
MY1
MY2
ft2
Cross Sectional Area
4.0
2.9
2.9
3.1
2.1
1.8
3.2
2.8
ft
Width
10.0
10.2
7.6
7.3
5.2
5.4
8.8
7.5
ft
Mean Depth*
0.4
0.3
0.4
0.4
0.4
0.3
0.4
0.4
ft
Max depth
0.6
0.5
0.7
0.7
0.5
0.6
0.8
0.7
entrenchment ratio
1.2
1.1
2.0
2.0
1.3
1.3
1.2
1.4
bank height ratio
3.0
3.4
4.3
4.4
4.0
3.7
4.0
4.4
ft/s
velocity
5.1
4.1
4.9
5.1
4.9
4.4
1.0
1.0
cfs
discharge rate
20.7
11.9
14.1
15.7
10.4
8.0
3.3
2.8
Ibs/ft2
shear stress
2.5
1.8
2.4
2.5
2.4
2.0
0.11
0.1
mm
threshold grain size
125.0
89.0
117.0
123.0
116.0
96.0
5.0
5.0
facet sloe
15%
15%
13%
2%
channel sloe
6.2%
*Mean depth set at 0.4ft based on the Mountain Rural Regional Curve for 0.03 sgmi watershed
High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 4 of 11

993
991
0 989
w
w 987
985
983
Cross Section 1
0 5 10 15 20
Station (ft)
-41-- MY2 10.26.2020 --G--MY111. 14.2019
High Hampton Golf Resort, LLC Golf Course
Holes 7 and 8 Culvert Removal and Stream Restoration Site
USACE Action ID No. SAW-2017-02281
25 30
Monitoring Year 2 of 3
October 2020
Page 5 of 11

994
992
0 990
w
988
986
984
Cross Section 2
0 5 10 15 20 25
station (ft)
�— MY2 10.26.2020 MY1 11.14.2019
30
High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 6 of 11

High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 7 of 11

High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 8 of 11

4.0 VISUAL MONITORING RESULTS
Visual monitoring data indicated that the stream is stable and performing well with no
significant bank erosion or bed scour. No aggradation or degradation was observed within
the project reach. A wooden footbridge was added since MY1, located near cross-section
4. The new bridge is visible in photo -point 5 facing upstream.
High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 9 of 11

High Hampton Golf Resort, LLC Golf Course
Holes 7 and 8 Culvert Removal and Stream Restoration Site
USACE Action ID No. SAW-2017-02281
Monitoring Year 2 of 3
October 2020
Page 10 of 11

5.0 MONITORING SUMMARY
This report represents the second of three annual monitoring reports, as required in the
permit conditions for USACE NWP 29 (SAW-2017-02281) Issued May 6, 2019 and
NCDWR Water Quality Certification Number 4134 issued March 22, 2019, "ensuring that
no streambank and/or streamed destabilization is occurring within the restored reach." CEC
concludes that the geomorphic and visual monitoring data collected for MY2 indicate that
the performance standards for stability are being met.
6.0 REFERENCES
Harman, W.H. et al. 2000. Bankfull Regional Curves for North Carolina Mountain
Streams. In: Kane, D.L. (Ed.). Proc. AWRA Conf. Water Resources in Extreme
Environments, Anchorage, AK. Pp. 185-190.
NCGS (North Carolina Geological Survey). 2004. Physiography of North Carolina.
Map compiled by the Division of Land Resources. Raleigh.
NCGS 1985. Geologic map of North Carolina: North Carolina Geological Survey,
General Geologic Map, scale 1:500000.
Rosgen, D. 1996. Applied River Morphology. Wildland Hydrology. Pagosa Springs,
Colorado.
High Hampton Golf Resort, LLC Golf Course Monitoring Year 2 of 3
Holes 7 and 8 Culvert Removal and Stream Restoration Site October 2020
USACE Action ID No. SAW-2017-02281 Page 11 of 11

FIGURES

High Hampton Golf Course Culvert Removal and Stream Restoration

High Hampton Golf Course Culvert Removal and Stream Restoration
Legend f��:,,� •
0 0.25 0.5 1 -
�_ _ Permitted Project Boundary — l Miles
Drawn by: AKT, 12.13.2019; CEC Project# 918 — F
Jackson County, CLearWaker USGS Topographic Map
North Carolina Cashiers Quad
32 Clayton Street Figure 2
Asheville, North Carolina 28801

High Hampton Golf Course Culvert Removal and Stream Restoration
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Legend
I r
rOrr
,
i
Permitted Project Boundar,.. ;.;: If ., ,; ,?;`
,
' I
,
I'
UT1 to Fowlers Creek Watershed (14 AC)
0 100 200 400
Monitoring Reach
Feet
Jackson County, CLear\Nater Aerial Photography
North Carolina NCCGIA (2019
32 Clayton Street Figure 3
Asheville, North Carolina 28801

High Hampton Golf Course Culvert Removal and Stream Restoration

High Hampton Golf Course Culvert Removal and Stream Restoration
PP3
O,
XS2
PP2/ 0
.,.PP5
XS4
XS3
PP4
j XS1
N
PP1 — —
0 50 100 200
r _V r� i Feet
i"
�4 Legend
/ r Permitted Project Boundary
Monitoring Reach (UT1 to Fowlers Creek) '
Cross -Section (XS)
Photgraphic Referece Point (PP)
Drawn by: AKT, 12.13.2019; CEC Project# 918 i.
Jackson County, CLear\Nater Monitoring Features Map
North Carolina Figure 5
32 Clayton Street
Asheville, North Carolina 28801

ATTACHMENT A:
Memo from Andrew Bick, PE, Headwaters Engineering
to David Brown, USACE and
Kevin Mitchell, NCDWR
RE: Stability Assessment and Stream Enhancements UTs to
Fowler Creek High Hampton Resort, Cashiers, Jackson County, NC

Headwaters Engineering, PC
NCBELS Lic. No. C-4500
MEMORANDUM
TO: David Brown, US Army Corps of Engineers
Kevin Mitchell, NC Division of Water Resources
FROM: Andrew Bick, PE
DATE: March 5, 2019
RE: Stability Assessment and Stream Enhancements
UTs to Fowler Creek
High Hampton Resort, Cashiers, Jackson County, NC
Approximately 880 linear feet (LF) of culvert was removed from an unnamed tributary to Fowler
Creek (referred to in the attached plans as UT 1) at the High Hampton Resort golf course, which
is currently undergoing a renovation. The banks of the daylighted channel were sloped and large
stone was placed in the bed and on the banks. A subsequent sediment removal effort was
completed at the request of DWR.
UT2 is located about 1,700 LF east of UT1 in the #2 fairway. The Corps and DWR expressed
concern with the height of the drop at the beginning of the UT2 channel at a headwall where two
culverts discharge, specifically with regard to stability and aquatic organism passage.
The purpose of this memo is to document as -built surveys completed by C1earWater
Environmental Consultants (CEC), to summarize our analysis of channel stability based on this
survey and our observations of the site, and to present proposed stream enhancements.
As -Built Surveys
In February 2019, CEC staff completed total station surveys of the daylighted UT channel and
UT2 near the headwall. The surveys were based on a local datum. The UT survey included
points along the top of both banks, the thalweg and water surface, four cross sections and several
ground points. The UT2 survey collected points along the thalweg of the channel and at a
transect immediately downstream of the headwall. The attached plans show the results of the
surveys superimposed on 2015 aerial imagery, which was collected prior to the stream
daylighting.
The plan view of UT 1 indicates a relatively straight alignment through roughly the low point of
the valley between a culvert under a cart path at the upstream end and a sediment trap at the
downstream end. The profile data indicate a slope of approximately 6 percent; the relatively
straight alignment would be expected for a slope in this range. The slope over the downstream
200 LF is noticeably flatter than the upstream 500 LF, apparently in response to the effects of the
sediment trap, which is currently a 3-foot tall riprap check dam. (In late January 2019,
Headwaters Engineering completed a laser level reference reach survey of UT1 downstream of

the sediment trap in order to support a design to remove the trap and create a stable transition to
a bedrock slide immediately downstream of the trap.)
Cross section surveys through the daylighted reach of UT indicate a relatively narrow and deep
channel, with width -depth ratios of 10 or less. Bank heights range from 2.4 to 3.2 feet and top
widths range from 11 to 20 feet. Cross section plots with dimension parameters are attached. As
shown on the attached photos, the bed and banks contain abundant riprap, generally ranging in
median size from 8 inches to more than 24 inches.
The UT2 survey indicates a drop of 1.8 feet from the invert of the north culvert to the thalweg
and a relatively flat slope of 1.8 percent from this point downstream. The cross-section survey
shows a relatively large channel with 3.4:1 side slopes and a maximum depth of 3.7 feet.
UT1 Stability Analysis
We used the USGS web -based hydrology tool StreamStats to estimate the drainage area above
the subject reach of UT and found it to be 22 acres. A digitized watershed boundary using the
Jackson County contours indicated a slightly smaller drainage area. Land use in the watershed
includes forest, the golf course and low density residential.
The North Carolina Mountain regional curve predicts a bankfull discharge of about 8 cubic feet
per second (cfs) for a 22-acre watershed. Previous experience indicates that regional curve
predictions at the extreme low end of the drainage area range such as this are not as reliable as
those in the middle of the range (between 2 and 30 square miles). Analysis of the surveyed riffle
cross sections indicates the discharge corresponding to the low bank stage is on the order of 140
to 200 cfs. The reference cross section survey by Headwaters in the relatively undisturbed
reference reach indicates a bankfull discharge of about 60 cfs.
Based primarily on a comparison to the reference reach cross section, it appears that the
daylighted channel was constructed deeper and wider than would have been designed based on a
natural channel design approach. Analyses of the as -built cross sections indicate shear stresses
in the riffles on the order of 5 to 6 pounds per square foot (psf). With reference to Shield's
equation, the predicted grain size for threshold of motion ranges from 240 to 300 mm, or 9 to 12
inches. Analysis of the reference cross section flowing full at a discharge of about 150 cfs
indicates a shear stress and threshold grain size similar to those of the constructed channel (4.8
psf and 230 mm, respectively).
We are aware of the daylighted channel being subjected to multiple flood events since it was
constructed and there does not appear to be bank erosion or bed scour. In our experience,
constructed streams are typically weakest immediately after construction and become more
resilient with time. The large stone in the channel and on the banks does not appear to have been
mobilized during any of these recent storms, and calculations indicate that even when flowing
full (well above the predicted "bankfull" discharge), the majority of the bed and bank materials
would not be mobilized. The proposed boulder steps at the downstream end of UT 1 will provide
additional grade control. A visual monitoring program over the next two to three years will
likely provide the data necessary to evaluate long term stream stability.
UT2 Perched Conditions
The concern expressed for UT2 is the high drop from the culverts to the receiving channel. The
proposed boulder step downstream of the headwall will reduce the drop height to about 9 inches,
and the proposed pool between the step and the headwall will help dissipate energy and promote

better aquatic organism habitat. As with UTl, the UT2 channel has been subjected to multiple
large floods and we have not observed stability issues even without the energy dissipation effects
of the proposed pool and step. A visual monitoring program seems appropriate for UT2 as well.
Closure
Based on our review of the data and our calculations, we do not recommend any repairs or
modifications to UTI at this time beyond the sediment trap removal and boulder steps at the
downstream end. For UT2, the proposed boulder step and pool should address energy
dissipation and aquatic organism passage concerns.
If you have any questions. please tail me at 828.606.0306.
Attachments:
Stream Enhancement Plans
Cross Section Plots and Shear Stress Calculations
Photos
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