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Table of Contents
1.0 Introduction
2.0 Project Goals
3.0 Existing Conditions
3.1 Watershed
3.2 Site Description
3.3 Channel Description
3.3.1 Channel Banks and Riparian zones
3.3.2 Riffle-Pool Complexes
3.4 Hydrology
4.0 Conc ept Plan
4.1 Planform
4.2 Cross Section
4.3 Bank Stabilization
4.4 Riparian Buffer
4.5 Park Features
List of Figures
Figure 1 Restoration Concept Plan
List of Photos
Photo A - Nested Channel downstream of Holden Road.
Photo B - Eroded bank on the south side of the upstream section.
Photo C - Eroded section along the south side of the upstream section.
Photo D - Downstream reach exhibiting bank erosion.
Photo E - Future site of the educational wetland.

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1.0 INTRODUCTION
KCI Associates of North Carolina, under contract to the North Carolina Department of
Transportation, has prepared this Conceptual Stream Restoration Plan for the tributary of
North Buffalo Creek in Starmount Park, Greensboro, Guilford County, North Carolina.
This plan serves as a working document, outlining the proposed stream
restoration/enhancement improvements as progress is made toward a final design that
will ultimately fulfill the project goals and specifications. The preliminary stream
restoration feasibility analysis conducted on this project identified sufficient deficiencies
on this reach to warrant restoration. These deficiencies included: 1. presence of bank
erosion and sloughing due to a lack of bank vegetation, encroachment, and disturbances
caused by "flashy" urban drainage, 2. widening of the channel in the upper reaches
prompting deposition of sediment load and loss of riffle complexes and 3. the need for
improved water quality and aquatic habitat. The potential to correct these deficiencies
was viewed as favorable due to several existing conditions: stable watershed hydrology
(due to minimal new development), bed lowering has ceased in most sections, stable
cross sections are developing, adjacent soils are supporting vigorous vegetation growth,
and adjacent forest areas add to the habitat value.
2.0 PROJECT GOALS
With an initial consensus that the subject tributary has both degraded functions and good
potential for restoration, the following set of goals and objectives were established to
guide the development of the conceptual restoration plan.
• Establish a stable channel geometry for low and high flows.
• Enhance warm water fisheries habitat.
• Enhance water quality and reduce localized erosion.
• Stabilize eroded banks.
• Protect adjacent structures/utilities from damage.
• Maintain and promote efficient sediment transport.
• Promote environmental awareness.
• Establish improved recreation access.
3.0 EXISTING CONDITIONS
3.1 Watershed
The subject watershed is located in the Piedmont physiographic region of central North
Carolina and drains a tributary to North Buffalo Creek. This watershed is approximately
769 hectares (1900 acres) and is predominantly sub-urban with significant drainage
occurring from the Starmount Forest Country Club (golf course) upstream of the site.
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The topographic relief of the watershed is 46 meters (150 feet) ranging from 286 meters
(940 feet) above mean sea level (MSL) in the northwest portion of the watershed and
declining to 240 meters (790 feet) above MSL at the confluence with North Buffalo
Creek. The landuses in the watershed are a combination of residential, institutional,
recreational, and open park, with single family homes comprising the majority of the
' residential areas in the immediate vicinity of the project site.
3.2 Site Description
' The section of stream under consideration for restoration/enhancement is an unnamed
tributary to North Buffalo Creek, in particular the section running through Starmount
' Park beginning at Holden Road and ending at the confluence with North Buffalo Creek
compromising approximately 1,555 meters (5,100 feet). Starmount Park is located in the
western portion of Greensboro, southeast of Hamilton Lakes and due north of Lindley
Park. The park is bisected by U.S. Route 421 (Market Street) at its approximate
midpoint. Starmount Park exhibits a typical park landscape including a baseball field and
' an all-purpose playing field with maintained turf and several areas of forest cover. In
addition an arboretum has been established on the western side of the stream in the lower
half of the study area.
3.3 Channel Description
' North Buffalo Creek in the project area is categorized as Class "C", "NSW" (Nutrient
Sensitive Waters) according to the Department of Environment, Health and Natural
Resources (DEHNR), Division of Water Quality (DWQ). The upstream section is
' approximately 701 meters (2,300 feet) from Holden Road to West Market Street. The
downstream section is approximately 853 meters (2,800 feet) from West Market Street to
the confluence with North Buffalo Creek. Channel slope throughout the study area is
fairly consistent (approximately 0.5 percent) with localized changes due to bedrock
outcrops, sewer crossings and culverts. In the upstream segment, at relatively stable
reaches, the channel geometry is represented by a nested channel with a low flow channel
inside in a higher flood flow channel (Photo A). The low flow channel width is .9-1.5
meters with depths of .45 meters; the high flow channel is approximately 7.6- 9.1 meters
wide with depths of .15-.45 meters above the low flow channel. Though less pronounced,
the downstream section also exhibits a nested channel with low flow (.9-1.2 meters wide;
.3-.6 meters deep) and high flow (4.6-6.1 meters wide; .3-.9 meters deep) surfaces. The
' floodplain areas, though fully vegetated, appear to be very active fluvial surface. Channel
substrate is variable, with frequently exposed sections of bedrock (felsic intrusive
complex) and regolith, as well as areas of sand and gravel. The combination of the large,
' residual cobbles and finer sediments produces a typical bi-modal distribution of sediment
throughout the system.
3.3.1 Channel Banks and Riparian Zones

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The riparian area of the stream, i.e. those areas in the 2 year floodplain, is primarily
mowed turf with some small areas of forest. Bank erosion is a significant problem within
the system with numerous areas being compromised for a variety of reasons.
Bank erosion in the upstream section is prevalent along sections of the right bank (south
side) with bank heights averaging 4-6 feet (Photos B & C). This erosion may be
attributable to a sanitary sewer which runs parallel to the stream along this section
restricting access to the floodplain on this side of the stream and the absence of well
rooted vegetation.
The downstream section, below West Market Street, is characterized by isolated reaches
of bank erosion, with the most significant section (approximately 500 linear feet)
occurring along the right bank of the park pedestrian trail system. Increased flows and
erosive capacity of the stream due to the upstream widening are likely contributing to this
erosion. A lack of bank vegetation, channel encroachment, and a "flashy" flow regime
tax the banks in these sections as well (Photo D).
3.3.2 Riffle-Pool Complexes
Riffle-Pool complexes are important features for the development of in-stream aquatic
habitats. For example, in some reaches, particularly in the upstream section, large deep
pools have formed near bedrock outcrops and are currently used by sunfish for spawning
beds. Riffle-Pool complexes generally establish (on average) at reoccurrence intervals
approximately six times the bankfull width. The estimated bankfull width (based on
visual observations and preliminary cross-section data) in this project area is
approximately 1.5-2.1 meters (5-7 feet), therefore, pools and riffles can be expected at 9-
13 meter (30-42 feet) intervals. This ratio is observed in the stable reaches but becomes
less pronounced in the sections which have been widened.
3.4 Site Hydrology
Preliminary existing hydrology for the Starmount Park site was established based on the
discharge estimates from Standard USGS Regional Regression Equations for North
Carolina (Blue Ridge Piedmont Region) and verified with field measurements. The
regression equations estimated discharges ranging from 8.66 cubic meters/second (305.8
cubic feet/second) for the two year storm event to 41.04 cubic meters/second (1449.1
cubic feet/second) for the one hundred year storm. This estimated data is not conclusive
and more detailed modeling must be conducted as progress is made toward the final
design. This may involve the implementation of a fully automatic flow monitoring
program through the installation of pressure transducers and data loggers. This specific
data will be used to refine the design and determine more accurate tractive forces on the
proposed bed and bank materials.
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4.0 CONCEPT PLAN
The Concept Plan ( Figure 1) for the restoration for this unnamed tributary of North
Buffalo Creek in Starmount Park illustrates a general breakdown of proposed changes in
planform, cross-section, bank stabilization, outfall features and educational value of the
project area. This proposal attempts to satiate the needs for improvements to in-stream
and riparian conditions, as well as creating new educational and recreational opportunities
for Starmount Park. This plan was prepared with the expectation that watershed
conditions are relatively static with only insignificant changes anticipated with respect to
watershed hydrology and sediment loading. A review of ultimate zoning, if available for
the watershed, will be conducted in the final design phase.
4.1 Planform
The majority of the current planform of the North Buffalo Creek project area is stable and
will not be adjusted from its present location. Several minimal adjustments may be
required in the section immediately upstream and downstream of West Market Street in
order to maintain a sediment transport reach. These alterations intend to reduce erosive
forces in the stream system and assist in re-establishing riffle-pool sequences.
4.2 Cross-section
In general, sections of this stream system exhibit a stable cross-section, however, several
modifications to over widened and degraded reaches are proposed in the plan. Minimal
adjustments to the cross-section in the vicinity of where the stream enters Starmount Park
and at the farthest reaches downstream before the stream exits the park at the confluence
with North Buffalo Creek are prescribed in the plan. The stable sections of the stream
will be used as a guide to effectively modify undersized or oversized sections. These
adjustments serve to reduce the existing steep channel banks while creating a stable
channel geometry that will be suitable for the accompanying bank stabilization
techniques.
4.3 Bank Stabilization
Four types of bank stabilization and combinations of techniques are proposed to stabilize
the banks. The following provides a brief description for each:
1) Brush layering - Brush layering is a technique where tightly configured rows of live
cuttings often black willow (Salix nigra) are placed perpendicular into the bank with the
growing tips oriented stream-ward. This technique produces a thick zone of vegetation
along the bank and is often used in areas of high potential velocities and tractive forces.
2) Fiber Rolls - Fiber rolls are manufactured rolls of fiber (often coconut) and
impregnated with various seed mixtures. Fiber rolls are generally staked into the channel
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banks and are excellent for protecting bank toes in the lower tractive force environments
such as in cross-over reaches.
' 3) Rock Toe/Joint Planting - This technique involves the use of a combination of bank
protection using rocks and vegetation. The bank face and bank toe are stabilized with
' appropriate sized rock material and selected vegetation (containerized or posts) are
interspersed between the rocks and into the bank substrate. This technique is used
typically along banks receiving potentially high velocities and tractive forces, such as at
' sharp stream bends and adjacent to roadway culverts.
4) Fiber Matting with Rock Toe and Fiber Roll - This technique is a combination
bank protection with fiber matting and toe protection using either a rock toe or fiber roll.
After the bank is graded, fiber matting is fastened down over exposed surfaces and
planted with stakes, posts, or rooted vegetative material. This technique has wide
applications and can be used in along most re-graded streambanks.
4.4 Riparian Buffer
An intrinsic part of the restoration plan is the establishment of a riparian buffer along the
' entire stream reach. Buffers increase the habitat value of the stream and protect the banks
from erosion. The proposed buffer will vary in width from 10 to 30 meters and will be a
combination of woody vegetation, trees and or unmowed turf areas. Specific areas will
' be incorporated into the buffer to allow stream access for educational or recreational
activities.
' 4.5 Park Features
In an attempt to increase public interest and enhance educational opportunities provided
' by the park, the restoration plan includes the development of a wetland adjacent to the
stream near a drainage from the adjacent activity fields. This feature will be
supplemented by a hiking trail that will span from the confluence area on the north side
' of the downstream section, upstream around the wetland area, continuing along the
outside of the riparian buffer, concluding before the junction with West Market Street.
' Educational signage will be incorporated into the trail to aid in an understanding of the
restored ecosystem. Several access points will also be provided in the section above
West Market Street to allow continued use of the warm water fishery that has developed
in this section. These areas will be stabilized in a manner that prevents degradation of the
stream and buffer by recreational activities.
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Tributary to North Buffalo Creek in Starmount Park
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Photo A - "Nested Channel" downstream of Holden Road.
Photo B - Eroded bank on the south side of the upsteam section.

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Photo C - Eroded section along the south side of the upstream section.
Photo D - Downstream reach exhibiting bank erosion.

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Photo E - Future site of the Educational Wetland.