United States Region 4 EPA 904/9-78-021
Environmental Protection 345 Courtland Street, NE
Agency Atlanta, GA 30308
SEPTEMBER 1978
v>EPA Environmental Draft
Impact Statement
Greensboro-Guilford County,
North Carolina
Horsepen Creek Interceptor
EPA Project No. C37036901
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DRAFT ENVIRONMENTAL IMPACT STATEMENT
GREENSBORO-GUILFORD COUNTY, NORTH CAROLINA
HORSEPEN CREEK INTERCEPTOR
EPA PROJECT NO. C37036901
Prepared by
Environmental Protection Agency
Region IV
345 Courtland Street, N.E.
Atlanta, Georgia 30308
Approved
d.
gional Administrator Date
In cooperation with
the State of North Carolina
Department of Natural Resources
and
Community Development
Raleigh, North Carolina 27611
Approved
DaCte
v/ vi;J:,,
icago, IL cO
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SUMMARY SHEET FOR ENVIRONMENTAL IMPACT STATEMENT
Greensboro-Guilford County, North Carolina
Horsepen Creek Interceptor
Project No. C-37036901
Draft (X)
Final ( )
Environmental Protection Agency
Region IV
345 Courtland Street
Atlanta, Georgia 30308
1. Type of Action: Administrative Action (X)
Legislative ( )
2. Brief Description of Proposed Action:
This Environmental Impact Statement was prepared in response
to the proposed action of awarding grant funds to Guilford County,
North Carolina for the purpose of developing a wastewater treat-
ment system to service the Greensboro-Guilford County area of
which the Horsepen Creek Interceptor is a part. The project con-
sists of the necessary facilities to transport wastewater from
the Horsepen Creek basin to the City of Greensboro wastewater
collection system for treatment. All of the Horsepen Creek
watershed and Lake Brandt, both of which are located entirely in
Guilford County, North Carolina, will be potentially affected by
the proposed action.
Physically, the proposed action consists of abandoning all
lift stations in the Horsepen Creek basin except the Albert Pick
lift station; construction of the Horsepen Creek interceptor and
collectors running to the abandoned lift stations; construction
of a new lift station and force main near U.S. Highway 220 to
transfer Horsepen Creek interceptor wastewater to the North
Buffalo Creek (NBC) collection system, and construction of a
new force main from the Albert Pick lift station to transfer
Deep River tributary wastewater to a new outfall discharging
to the South Buffalo Creek (SBC) collection system. All lines
are sized to serve the existing population in the Horsepen Creek
basin, plus only limited additional capacity.
The proposed action will provide for:
(1) the elimination of the present system of lift
stations and force mains in the area,
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(2) a new collection system providing for transfer
of existing wastewater flows in Horsepen Creek
basin to the City of Greensboro wastewater
collection system,
(3) allowance for controlled growth during urbaniza-
tion of the Horsepen Creek basin, and
(4) sewering of areas with failing septic tanks.
3. Summary of Major Environmental Impacts
Direct adverse impacts associated with the proposed action
are minor. Construction of the interceptor system will cause
short-term, minor stream siltation and increased airborne
particulates. Some natural vegetation will also be destroyed,
continuing a trend to habitat fragmentation. Certain individuals
will be subjected to temporary noise levels that exceed accept-
able thresholds. Urbanization of the Horsepen Creek basin will
probably be accelerated somewhat as a result of this project.
Low density development with widespread septic tank use, as op-
posed to high density development with full sanitary sewerage,
will be promoted. This will tend to minimize the deleterious
effects of urban runoff on Horsepen Creek and ultimately on Lake
Brandt. Likewise, the proposed action will necessitate that
adequate growth management planning measures be adopted and cur-
rent regulations be strictly enforced by local officials. This
is necessary to ensure that contamination of the City of Greens-
boro's water supply in Lake Brandt does not occur as a result
of expected growth in the Horsepen Creek watershed.
Significant adverse secondary impacts include an unavoidable
lowering of water quality in Horsepen Creek due to urbanization.
Land use changes accompanying increased urbanization will vir-
tually eliminate farmland and forested areas in the basin, and re-
duced sediment loads to Horsepen Creek may promote eutrophication
in Lake Brandt. Concentrations of pollutants in stormwater runoff,
especially lead, will increase as urbanization of the basin occurs,
which may result in unacceptably high levels of pollutants in
Lake Brandt. Arsenic levels may increase as well if its concen-
tration in Lake Brandt is dependent on pH of inflowing waters.
Major beneficial impacts include elimination of the present
system of lift stations and force mains in the basin which have
occasionally surcharged in the past. Many poorly designed or
malfunctioning septic tank systems in current use will be eli-
minated. Finally, this project will promote the development of
planning measures for orderly urban growth in the Horsepen Creek
basin which are necessary to protect the City of Greensboro's
water supply in Lake Brandt.
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4. Summary of Alternatives Considered
The EIS process identified six (6) system alternatives for
this project. These alternatives were subjected to a multilevel
evaluation process (involving environmental, engineering, legal
and cost constraints) and inputs from the Greensboro-Horsepen
Creek EIS Advisory Committee. Alternatives 1 through 4 can be
sized to serve either existing or future development.
Alternative 1 - abandon all lift stations in Horsepen Creek
basin except Albert Pick lift station; construction of Horsepen
Creek (HC) interceptor and collection lines to abandoned lift
stations; construction of new lift station and force main near
U.S. Highway 220 to transfer wastewater from HC interceptor to
North Buffalo Creek (NBC) collection system.
Alternative 2 - abandon all lift stations in HC basin except
Albert Pick lift station; construction of HC interceptor and col-
lection lines to abandoned lift stations; construction of a new
force main from Albert Pick lift station to new outfall discharg-
ing to South Buffalo Creek (SBC) collection system; construction
of new lift station and force main near U.S. Highway 220 to trans-
fer HC interceptor wastewater to NBC collection system.
Alternative 3 - abandon all lift stations in the HC basin ex-
cept Stage Coach Trail, Wagon Wheel, and Albert Pick lift sta-
tions; Stage Coach Trail lift station will transfer wastewater to
SBC collection system; construction of HC interceptor from Fleming
Road-New Garden Road intersection to U.S. Highway 220 and collec-
tion lines to abandoned lift stations; construction of new lift
station and force main near U.S. Highway 220 to transfer HC inter-
ceptor wastewater to NBC collection system.
Alternative 4 - abandon all lift stations in HC basin except
Stage Coach Trail, Wagon Wheel, and Albert Pick lift stations;
Stage Coach Trail lift station will transfer wastewater to SBC
collection system; construction of new force main from Albert
Pick lift station to new outfall discharging to SBC collection
system; construction of HC interceptor from Fleming Road-New
Garden Road intersection to U.S. Highway 220 and collection lines
to abandoned lift stations; construction of new lift station and
force main near U.S. Highway 220 to transfer HC interceptor waste-
water to NBC Collection system.
Alternative 5 - No Action - maintain existing HC collection
system; new wastewater sources in excess of capacity must be ac-
commodated by septic tank systems.
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Alternative 6 - Modified No Action - construction of new
force main from Albert Pick lift station to new outfall dis-
charging to SBC collection system; existing HC collection system
will be maintained and operated with the addition of standby
power.
5. Comments on the Draft Statement Have Been Requested from
the Following!
Federal Agencies
Bureau of Outdoor Recreation
U.S. Coast Guard
Corps of Engineers
Council on Environmental
Quality
Department of Commerce
Department of Health,
Education and Welfare
Department of the Interior
Department of Transportation
Department of Housing and
Urban Development
Economic Development Administra-
tion
Federal Highway Administration
Fisheries and Wildlife Service
Food and Drug Administration
Forest Service
Geological Survey
National Park Service
Soil Conservation Service
Department of Energy
Federal Power Commission
Members of Congress
Honorable Robert Morgan
Honorable Jesse A. Helms
Honorable Richardson Pryor
U.S.
U.S.
U.S.
State
Senate
Senate
House of Representatives
James B. Hunt, Governor
Office of Intergovernmental Relations
Council of Governments
Division of Archives and History
Commission of Agriculture
Office of State Planning
North Carolina Wildlife Resources Commission
Local
Mayor, City of Greensboro, North Carolina
Chairman, Guilford County Commission
Chairman, Piedmont Triad Council of Governments
Interested Groups
Greensboro Chamber of Commerce
Board of Realtors
IV
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Interested Groups (Continued)
Greensboro Citizens Association
North Carolina A&T University
Environmental Action Coalition
League of Women Voters
Rural/Suburban Community
The Sierra Club
Guilford County Advisory Board for Environmental Quality
Concerned Citizens of McLeansville
McLeansville Community Council
Piedmont Council of Engineering and Technical Societies
NAACP
GATEWAYS
McLeansville Merchants Association
Greensboro Jaycees
Audubon Society
Homebuilders Association
6. Date Made Available to QFA and the Public
The Draft Statement was made available to OFA and the Public
in October 1978.
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TABLE OF CONTENTS
Page
SUMMARY SHEET FOR ENVIRONMENTAL IMPACT STATEMENT i
EXECUTIVE SUMMARY ix
1.0 INTRODUCTION 1
2 . 0 DESCRIPTION OF THE PROPOSED ACTION 5
3.0 ALTERNATIVES 11
3.1 Description of Alternatives Considered 12
3.1.1 Configuration 12
3.1.1.1 Alternative 1 12
3.1.1.2 Alternative 2 13
3.1.1.3 Alternative 3 13
3.1.1.4 Alternative 4 16
3.1.1.5 Alternative 5 16
3.1.1.6 Alternative 6 20
3.1.2 Collection Line Sizes 20
3.2 Environmental Evaluation of Alternatives 24
3.2.1 Air Quality 26
3.2.2 Land Resources 28
3.2.3 Water Resources 30
3.2.4 Biological Resources 33
3.2.5 Cultural (Man-Made Resources) 35
3.2.5.1 Demography and Economics 35
3.2.5.2 Land Use 36
3.2.5.3 Community Services and
Facilities 37
3.2.5.4 Taxes and Budgeting 37
3.2.5.5 Archaeological, Cultural,
Historical, and Recreational
Resources 38
3.2.6 Summary 38
VI
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TABLE OF CONTENTS (Continued)
Pa?
3 . 3 Cost Analysis of Alternative 39
3.4 Selection of Proposed Action 40
4.0 DESCRIPTION OF THE AFFECTED AREA 42
4 .1 Environmental Context 43
4.2 Areas of Significant Impact 47
4.2.1 Soils 47
4.2.2 Water Quality 53
4.2.2.1 Ground-Water Quality 53
4.2.2.2 Surface-Water Quality 55
4.2.3 Biological Components 68
4.2.3.1 Terrestrial Environment 68
4.2.3.2 Aquatic Environment 75
5 . 0 EFFECTS OF THE PROPOSED ACTION 82
5 .1 The Natural Environment 83
5.1.1 Air Quality 83
5.1.2 Odor 84
5.1.3 Noise 85
5.1.4 Soils 86
5.1.5 Hydrology 88
5.1.5.1 Ground Water 88
5.1.5.2 Surface Water 90
5.1.6 Biological Components 98
5.1.6.1 Land 98
5.1.6.2 Water 99
5.1.6.3 Sensitive Areas 100
5 . 2 The Man-Made Environment 101
5.2.1 Land Use 101
VII
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TABLE OF CONTENTS (Continued
Page
6 . 0 MITIGATING MEASURES 104
6.1 Water Quality 105
6 . 2 Land Use 107
6 . 3 Cultural Resources 110
7 . 0 PUBLIC PARTICIPATION Ill
BIBLIOGRAPHY 114
APPENDIX 118
Vlll
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EXECUTIVE SUMMARY
This Environmental Impact Statement was prepared joint-
ly by the State of North Carolina Department of Natural Resources
and Community Development and the Environmental Protection Agency,
Region IV, in response to legal requirements of the State of North
Carolina and the United States. It addresses those areas stipu-
lated by the National Environmental Policy Act of 1969, the North
Carolina Environmental Policy Act of 1971, and the Council on
Environmental Quality Guidelines of August, 1973.
1. Existing Environment
For the purposes of this Environmental Impact Statement
(EIS), the study area includes all of the Horsepen Creek basin,
as shown in Figure 1. The total environment is divided into
natural and man-made aspects and each, while interactive, is
discussed separately. Supporting documentation is provided in a
Technical Reference Document (RA-R-507) and the Greensboro Draft
EIS (EN-R-618).
a. Natural Environment
The Horsepen Creek basin area has a temperate climate
with short, mild winters and long, hot summers. Precipitation
is abundant.
Air pollutant emissions of the adjacent Greensboro area
are typical of a moderately industrialized urban region, The
general quality of the Greensboro area is good with respect to
criteria pollutants. Guilford County has been designated an Air
Quality Maintenance Area for suspended particulates.
Community-wide odor problems do not exist in the Horse-
pen Creek basin.
The noise climate of the study area is typical of simi-
lar suburban areas in the United States. Residential areas are
characterized by low to moderate levels which, in most cases, do
not intrude upon outdoor activities. Higher noise levels are
present near major traffic arteries and the airport.
The topography of Guilford County is typical of the
Piedmont Plateau physiographic province in that it is gently rol-
ling in the uplands and somewhat more rugged near the major
streams. The bedrock of the county consists of igneous and
metamorphic rocks that are also typical of the Piedmont province.
The bedrock is overlain by a thick mantle of saprolite (soft,
weathered bedrock) in most of the county. The most important
geologic processes are ground-water recharge and flooding.
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ROCKINGHAM CO.
HORSEPEN CREEK BASIN
Figure 1. Location of Horsepen Creek Study Area
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The soils of the Horsepen Creek basin are typical soils
of the Piedmont uplands. Surface horizons are generally less
than one foot in thickness and are composed of brown or sandy
loam. Subsoils consist of red clay and are two to four feet in
thickness. The soils are mostly developed on deeply weathered
saprolite. Most of the Horsepen Creek soil series outside the
floodplain areas have phases that are considered prime farmland
soils. Nearly all of the soils in the study area are poorly
suited to septic tank use, primarily because of low permeability
in the subsoil horizon.
Horsepen Creek is the only stream in the study area.
The 7-day, 10-year low flow is less than 2 cfs, and average flow
is approximately 17 cfs. BOD levels are low and DO levels are
high, indicating the current high water quality in Horsepen Creek.
Some problems exist with high fecal coliform levels due to septic
tank contamination. The stream is presently classified for drink-
ing water use with a class A-II rating by the state of North
Carolina. Horsepen Creek is a major water supply for Lake Brandt,
a municipal water use reservoir for the city of Greensboro. Lake
Brandt is considered moderately eutrophic. High turbidity which
limits light penetration is probably responsible for preventing
the growth of aquatic macrophytes or nuisance algal blooms, since
adequate nutrient concentrations for excessive growth of aquatic
flora are present in the lake. Preservation of Horsepen Creek
water quality is widely perceived as a necessity in order to pro-
tect the Greensboro water supply in Lake Brandt.
Because of the geologic setting of Guilford County,
major regional aquifers do not exist. However, shallow, low-pro-
ductivity water-table aquifers are present and serve as important
water sources in rural areas. The ground water of these aquifers
occurs in pore spaces in the saprolite and in fractures in the
underlying bedrock. Recharge to the aquifers occurs in the up-
lands, and discharge is to wells or as baseflow to the streams.
The total ground water available in the county is estimated to be
about 150 MGD, but only approximately 11 MGD is presently being
used. Ground-water quality is generally good, except for a high
iron content in some areas. Ground-water quality problems from
septic tanks have been reported in the county.
The potential natural vegetation in the Horsepen Creek
area is a climax hardwood forest. Man's use of the area has re-
sulted in the establishment of a mixed oak-hickory-pine forest
type which is now fragmented by cultivated fields, old fields,
and urban areas. No virgin woodlands remain. About 38 percent
of the total land in the study area is forested with second growth
woodlands in various stages of succession.
Because man's use of the study area has fragmented the
natural vegetation, forest species have decreased while species
XI
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preferring disturbed habitats have increased. Small game animals
and game birds have benefitted from fragmentation of the wood-
lands. Other game animals such as whitetail deer and wild turkey
have been practically eliminated. Species tolerant of or espe-
cially adapted to man's alterations in natural conditions are
generally characteristic of the area's fauna.
Sport fishing is restricted to Lake Brandt in the study
area; habitat adequate for game fish in Horsepen Creek is probably
restricted to a few small pools. However, benthic invertebrates
are numerous and diverse in Horsepen Creek. The fresh water marsh
located at the confluence of Horsepen Creek and Lake Brandt rep-
resents a unique habitat in the study area and is considered
particularly sensitive to development.
No virgin woodland i stands remain in the study area.
Three plant species are listed as "threatened" throughout their
range in North Carolina. The southern rain orchid (Habenaria
flava), Nestronia (Nestronia umbellula), and ginseng are all moist
lowland species. 'None of the mammals of Guilford County are con-
sidered endangered. The Bald Eagle once nested in the area and
the Peregrine Falcone migrates through the region. Both are con-
sidered endangered by the U.S. Fish and Wildlife Service. The
sharp-shinned hawk is considered threatened and is reported to
nest near Lake Brandt. Species which are sensitive in the area
because they are relictual populations or occur at the edge of
their range include the white-crowned sparrow, crescent shiner,
and an unidentified species of freshwater clam.
b. Man-Made Environment
The Horsepen Creek study area had 8,080 people in 1975
and is projected to have 18,700 in 2000. The land use pattern is
a mixture of low-density suburban development along the eastern
boundary, commercial and industrial in the southwestern portion,
and agricultural and forest land along the western boundary.
The Greensboro area economy has grown since 1970 with
20,000 jobs created in Guilford County from 1970 to 1974. Unem-
ployment has been low in recent years (normally under four per-
cent) . Manufacturing dominates the employment structure with
textile employment being conspicuously important. Employment in
manufacturing sectors such as wholesale/retail trade and services
has grown in recent years.
Greensboro and Guilford County are providing police
and fire protection, health care, education, waste disposal,
libraries, and other public services that are essential. Greens-
boro and Guilford County are financially sound governments, pay-
ing for their needs with very little bonding required.
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The Guilford County area has a rich cultural heritage
which is being enhanced and protected. National Register his-
toric sites are located in Greensboro and many buildings and
areas of historic value have been identified. Also, the area
may have archaeological resources, but they are not well known
at this time. Recreational resources are scattered throughout
the city and county.
As a focal point of North Carolina highways, Greensboro's
major thoroughfares are heavily used. Thoroughfares are planned
to relieve excess traffic loads as they develop, especially in
peripheral areas.
Duke Power Company will be able to meet the area's
energy requirements through the year 2000 as long as coal and
nuclear fuels are available. No major natural resources are
being extracted in the study area.
2. System Alternatives
All system alternatives were developed with the assump-
tion that an additional 10,620 people will move into the Horsepen
Creek basin over the next 20 years providing sanitary sewerage is
available. A total of six alternatives were considered, including
No Action and a Modified No Action scheme. These alternatives
were tested in a multilevel screening process involving environmen-
tal, engineering, legal and cost constraints, and inputs from the
Greensboro-Horsepen Creek EIS Advisory Committee. A summary of
these alternatives follows. Alternatives 1 through 4 are de-
picted graphically in Figure 2. The linework proposed for the
Modified No Action Alternative is represented graphically in
Alternatives 2 and 4. Alternatives 1 through 4 can be sized to
serve either existing or future development.
Alternative 1 - abandon all lift stations in Horsepen
Creek basin except Albert Pick lift station; construction of
Horsepen Creek (HC) interceptor and collection lines to abandoned
lift stations; construction of new lift station and force main
near U. S. Highway 220 to transfer wastewater from HC interceptor
to North Buffalo Creek (NBC) collection system.
Alternative 2 - abandon all lift stations in HC basin
except Albert Pick lift station; construction of HC interceptor
and collection lines to abandoned lift stations; construction of
a new force main from Albert Pick lift station to new outfall dis-
charging to South Buffalo Creek (SBC) collection system; construc-
tion of new lift station and force main near U. S. Highway 220 to
transfer HC interceptor wastewater to NBC collection system.
Xlll
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"V.J81"
Figure 2. Horsepen Creek Wastewater Interceptor Alternative Numbers 1, 2, 3, & 4
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Alternative 3 - abandon all lift stations in HC basin
except Stage Coach Trail, Wagon Wheel, and Albert Pick lift sta-
tion; Stage Coach Trail lift station will transfer wastewater to
SBC collection system; construction of HC interceptor from'Fleming
Road-New Garden Road intersection to U. S. Highway 220 and collec-
tion lines to abandoned lift stations; construction of new lift
station and force main near U.S. Highway 220 to transfer HC in-
terceptor wastewater to NBC collection system.
Alternative 4 - abandon all lift stations in HC basin
except Stage Coach Trail, Wagon Wheel, and Albert Pick lift sta-
tions; Stage Coach Trail lift station will transfer wastewater to
SBC collection system; construction of new force main from Albert
Pick lift station to new outfall discharging to SBC collection
system; construction of HC interceptor from Fleming Road-New Garden
Road intersection to U.S. Highway 220 and collection lines to
abandoned lift stations; construction of new lift station and
force main near U.S. Highway 220 to transfer HC interceptor waste-
water to NBC collection system.
Alternative 5 - No Action - maintain existing HC col-
lection system; new wastewater sources in excess of capacity must
be accommodated by septic tank systems. x
Alternative 6 - Modified No Action - construction of
new force main from Albert Pick lift station to new outfall dis-
charging to SBC collection system; existing HC collection system
will be maintained and operated with the addition of standby
power.
3. Description of the Proposed Action
The proposed action for wastewater collection system
improvements in the Horsepen Creek basin is Alternative 2, which
is sized for existing development plus very limited additional
capacity and is composed of:
abandonment of all lift stations except the
Albert Pick in HC basin
construction of HC interceptor along the creek
and collection lines to abandoned lift stations
to provide service to existing developed areas
construction of a new force main from the
Albert Pick lift station to transfer Deep
River tributary wastewater to a new outfall
discharging to the SBC collection system
construction of a new lift station and force
main near U.S. Highway 220 to transfer HC
interceptor wastewater to the NBC wastewater
collection system.
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To ensure that certain safeguards are adopted, the dis-
bursement of grant funds will be subject to the following condi-
tions :
Potentially affected areas will be surveyed to
determine the presence of possible archaeological
resources. This survey will be accomplished during
the Step 2 process and the survey plan and results
will be subject to approval by the North Carolina
State Historic Preservation Officer and State
Archaeologist.
If possible and complying with good engineering
practices, interceptor lines should be constructed
completely out of or on the edges of the floodplain.
This condition should be evaluated during Step 2.
An erosion and sedimentation control plan must be
submitted to DNRCD and EPA for approval of its
acceptability,
The maintenance of a 30-foot vegetative buffer
between the edge of construction rights-of-way
and stream banks will be required where feasible.
The immediate revegetation of interceptor rights-
of-way will be required.
^ Environmental Effects of the Proposed Action
a. Natural Environment
Direct air quality impacts of the proposed action will
occur during the construction phase. Only total suspended par-
ticulates (TSP) are of any concern. A short-term increase in
TSP levels from fugitive dust emissions may be expected to occur.
Indirect impacts associated with the predicted urbanization of
the Horsepen Creek area will be an elevation of ambient levels of
all the criteria air pollutants .
No adverse odor impacts are expected as a result of the
proposed action. A slight decrease in odor levels may occur due
to elimination of several lift stations that occasionally sur-
charge .
Noise levels in the area will increase during the
struct ion phase as a result of heavy equipment operation. Ambient
noise levels will increase gradually due to urbanization and at-
tendant increases in traffic, construction, etc.
xvi
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No significant geological impacts are expected. Soil
will be lost due to erosion during construction of the intercep-
tor system. Urbanization of almost all prime farmland soils in
area will be an indirect impact of this project. But this land
use change is expected to reduce soil loss due to erosion.
Ground-water supplies should not be affected appreciably
by this project. Total recharge in the area will be reduced
slightly due to the increases in impervious area expected as a
result of urbanization. Ground-water quality should not be ad-
versely affected if good engineering practices are used to pre-
vent exfiltration from the proposed sewer system, and the capacity
of the lines is not exceeded. Existing septic tank problem areas
will be provided with sewer service. The possiblity of future
septic tank problems should be alleviated by strict enforcement
of the new Guilford County septic tank ordinance.
The major direct impacts of the project on surface water
quality will be improvements in quality due to the sewering of
existing septic tank problem areas and the elimination of the
system of lift stations. A short-term increase in sediment loads
during construction is the major adverse direct impact. Indirect
impacts are related to the predicted increase in non-point source
pollution due to urbanization of the Horsepen Creek watershed.
Ultimately, these impacts will be substantially less under the
proposed action than they would be if the future service alter-
native were selected.
BOD, phosphorus, and heavy metals concentration are
expected to increase in Horsepen Creek. Suspended solids and
dissolved oxygen levels are expected to decrease. These changes
in Horsepen Creek water quality will have an impact on Lake
Brandt water quality as well. Reduced suspended solids levels
will lower turbidity in the lake, and this, in turn, may promote
eutrophication and the occurrence of nuisance algal blooms. Lead
and arsenic levels may increase as a result of urbanization,
presenting a serious problem to use of Lake Brandt water for
drinking water purposes in Greensboro.
Direct impacts on the biological communities in the
Horsepen Creek basin as a result of this project will be minor.
Approximately 123 acres will be seriously disturbed during the
construction phase. Indirect impacts Twill be more significant
as urbanization occurs. The terrestrial habitats in the area
will become more fragmented, favoring those plants and animals
which are adapted to a closer association with man. The aquatic
habitat in Horsepen Creek may be impaired if non-point source
pollution increases. Any increase in pollutants will favor those
aquatic organisms which are adapted to their presence, A de-
crease in aquatic biota diversity can be expected.
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b. Man-Made Environment
Most of the land now presently under cultivation or
forested will be converted to residential use under all project
alternatives. The pattern of development should follow established
trends with commercial and industrial development occurring pri-
marily in the southwestern portion of the basin. Future sub-
divisions with sewers will probably occur adjacent to the already
sewered areas. The necessity of a low density septic tank develop-
ment in order to protect the Greensboro water supply in Lake Brandt
will result in a more costly public services system. Under any
alternative for the provision of sewer service almost all avail-
able land in the basin that is not environmentally sensitive will
eventually be developed. Development of sensitive areas would
have serious impacts, and should be restricted.
*>. Mitigating Measures
General mitigating measures regarding the direct im-
pacts of construction of an interceptor system on air quality,
noise, soils, etc., are not discussed in this report. The in-
terested reader is referred to the appropriate sections in the
Greensboro EIS (EN-R-618) for this information. Mitigating
measures concerning water quality and land use, those areas
where significant adverse impacts can be expected to occur, are
summarized in the following paragraphs.
Preservation of water quality in Horsepen Creek is largely
the responsibility of the local governments in the area. As part
of a program to preserve water quality, it is recommended that
the appropriate governmental bodies initiate the following:
development of a Section 208 planning program
a regular water quality monitoring program for
Horsepen Creek and Lake Brandt
a comprehensive runoff control ordinance
enforcement of the county subdivision ordinance
restricting any development within the Horsepen
Creek floodplain
restriction of any development in the. fresh-
water marsh at the confluence of Horsepen
Creek and Lake Brandt
legal restrictions preventing future tie-ins
to the Horsepen Creek interceptor system be-
yond its design capacity
xvi 11
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strict enforcement of the Guilford County
septic tank ordinance
acquisition of lands for recreation and
conservation
Minimizing adverse impacts related to land use will
require Greensboro and Guilford County officials to plan for a
particular growth scenario and implement controls to insure that
development follows the plan. The Master Plan currently under
consideration is a step in that direction. The "Open Space Pro-
gram" of January, 1977, and the "Land Use Goals and Policies"
statement of Guilford County demonstrate the desire of county
officials for balancing development interests with environmental
considerations.
In short, it appears that many of the control measures
required to promote orderly land use and prevent development in
environmentally sensitive areas are already in existence in some
form or are under consideration. Strict enforcement of existing
measures together with the institution of the additional measures
proposed will provide a comprehensive program for water quality
protection.
xix
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CHAPTER 1
INTRODUCTION
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1.0 INTRODUCTION
All agencies of the federal government and the State
of North Carolina are required by law* to prepare a detailed
environmental impact statement (EIS) for major legislative and
administrative actions significantly affecting the quality of
the human environment. The objectives of implementing the
EIS process are to (1) build into the decision-making process
an appropriate and careful consideration of all environmental
aspects of proposed actions, (2) explain potential environmental
effects of proposed actions and their alternatives for public
understanding, (3) avoid or minimize adverse effects of pro-
posed actions, and (4) restore or enhance the quality of the
environment as much as possible.
The North Carolina Department of Natural Resources and
Community Development in concert with the Environmental Protec-
tion Agency determined that the issuance of federal and state
funds for improvements to the Greensboro, North Carolina, waste-
water treatment facilities constitutes a major action that poten-
tially could significantly affect the quality of the human
environment. Consequently, decisions were made to prepare a
joint federal-state EIS, the Notice of Intent for which was re-
leased on April 5, 1976. Specific considerations of the environ-
mental acceptability of the Horseperi Creek interceptor were
included in this EIS. In investigating the secondary water-
related effects of this interceptor, a rather lengthy monitoring
study was required. Because (1) the Horseperi basin development
-''National Environmental Policy Act of 1969 (NEPA) , 16 U.S.C. 4321
e_t seq. , as implemented by Executive Order 11514 of March 5, 1970,
the Council on Environmental Quality (CEQ) Guidelines of August
1, 1973; North Carolina Environmental Policy Act of 1971 (1971
C. 1203; 5.1), N.C. Gen. Stat. Ch: 113A (Cum. Supp. 1973).
-------
was a separable issue from both historical and technological
perspectives, and (2) it was in the interest of the total
Greensboro 201 planning effort not to delay the post-Step 1
activities for the rest of the proposed facilities, EPA and
the State subsequently decided in 1977 to prepare a separate
EIS on the Horsepen Creek Interceptor. This report documents
these NEPA activities related to Horsepen Creek. This EIS
should be viewed as a companion to the Draft and Final EIS
for the Greensboro-Guilford County 201 Wastewater Treatment
System (EN-R-618, EN-R-687). These documents have been filed
with the Council on Environmental Quality and the North Carolina
Division of Environmental Management. They contain basic site-
and activity-specific information that forms the basis for this
EIS and are appended to this document by reference.
Horsepen Creek is situated on the northwestern
fringe of the Greensboro metropolitan area and lies along one
of the paths of suburban growth of the city. Part of the basin
is already developed, with wastewater services provided by a
network of collectors, lift stations, and force mains and by
residential septic tanks. Horsepen Creek and Reedy Fork to
the north are impounded to form Lake Brandt, which is one of
the city's water supplies. Water supplies are not abundant
in the Greensboro area, due to its location in the headwaters
of relatively small streams. As such, supplies will be strained
to meet water demands by the end of this century. The water
quality impacts of developing the Horsepen Creek watershed
are a source of major concern among some interested parties,
and in large measure have instigated this EIS.
-------
Three generic types of structural alternatives are
considered in this assessment: no action, service for currently
existing population, and service for the projected future popu-
lation. In addition, several physical configurations (i.e.,
routes and phasing) of the collector-interceptor system are
possible, and a variety of non-structural measures related to
institutional controls are considered. The proposed action
constitutes the emplacement of an interceptor of restricted
size designed to convey only the existing wastewaters that are
generated within the basin. The total project capital cost
for the selected alternative is $1.38 million, of which 75
percent will be provided by EPA and 12% percent will be eligible
for state funding. Annual operation and maintenance costs are
only $8,500. The cost difference among the alternatives is
very small, relative to the total cost of the Greensboro 201
facilities.
The preparation of this EIS has been guided by the
proposed regulations of the Council on Environmental Quality for
implementing NEPA (Federal Register, Volume 43, June 9, 1978).
It is organized into chapters that summarize sequentially
what the proposed action is, why it has been selected from
available alternatives, what are the characteristics of the
affected area, what are the environmental consequences, and
what mitigative measures are available to lessen potential ad-
verse impacts. The public participation program is described
in the last chapter of this EIS.
-------
CHAPTER 2
DESCRIPTION OF THE PROPOSED ACTION
-------
2° DESCRIPTION OF THE PROPOSED ACTION
The proposed action for sewer system improvements to
the Horsepen Creek service area includes abandoning all lift
stations in the Horsepen Creek drainage basin and constructing
an outfall interceptor from the Stage Coach Trail lift station
along Horsepen Creek to U.S. Highway 220. A new force main will
be constructed near Interstate 40 to transfer Deep River tribu-
tary wastewater from the existing Albert Pick lift station to
the South Buffalo drainage basin and into a new outfall sewer
which will discharge to the South Buffalo Creek collection sys-
tem. New collectors will be constructed from the abandoned lift
stations to the new Horsepen Creek interceptor to provide ser-
vice to the existing developed areas. A new lift station and
force main will be constructed near U.S. Highway 220 to transfer
wastewater from the new Horsepen Creek interceptor to the North
Buffalo Creek wastewater collection systems. All new facilities
will be designed or sized to accommodate the existing wastewater
flows. However, minimum pipe sizes allowable for sewer construc-
tion as is used in this design will accommodate a service popula-
tion of approximately 12,000 people. A schematic of the proposed
collection and transfer wastewater system is shown in Figure 2-1.
The exact number of people which could be served by the project
will not be known until the Step 2 design is completed because
of the effect of slope upon pipe capacity.
Facilities for the proposed action are designed to
transfer approximately 1.3 MGD of domestic flow and approxi-
mately 1.1 MGD of industrial flow from the Horsepen Creek basin
to the North and South Buffalo Creek basins, respectively, for
treatment. Excluding the individual service laterals, the pro-
posed facilities consist primarily of approximately 51,140
lineal feet of gravity sewer, 20,000 lineal feet of pressure
mains, a 1.1 MGD lift station, and approximately 150 manholes.
6
-------
Gravity sewers will be constructed of either vitrified clay
pipe or PVC pipe and pressure mains will be constructed of
either cast iron or concrete pipe. Manholes will be spaced
approximately 400 feet apart along the gravity outfall.
An inventory of the various transmission lines, as
delineated in Figure 2-1, with design flows, recommended pipe
sizes, and pipe lengths is shown in Table 2-1. Gravity sewers
are designed on the basis of flowing two-thirds full at peak
flow with a minimum velocity of 2 feet per second and a maximum
velocity of 10 feet per second. Force mains are designed on the
basis of flowing full at peak flow within the same velocity
boundaries.
A new 50 horsepower lift station will be constructed near U.S.
Highway 220 with a capacity to deliver approximately 1.1 MGD.
Construction of these facilities will occur over ap-
proximately two years and will result in temporary disturbance
of about 330 acres. Excavation depths will average 5 feet with
maximum depth of approximately 10 feet.
Construction of the facilities will require the em-
ployment of approximately 40 workers at any one time. Job
responsibilities will range from skilled to unskilled positions
and will include laborers, equipment operators, welders, and
mechanics. No phasing of construction activities will be
necessary.
Operation and maintenance requirements for the facili-
ties will include operation of the two lift stations and periodic
inspection, cleaning, and possible repairs of the transmission
lines. Annual consumption of electricity for operation of the
lift station will approximate 400 thousand kwhr.
-------
00
r TO NOPTH
BUFFALO O/F
\
TO NORTH
BUFFALO O/F
LEGEND:
MAJOR ROAD
DRAINAGE BOUNDARY
SANITARY SEWEH SFRVICF AREA
LIFT STATION
» » FORCE MAIM
- GRAVITY SEWi;n
0 4000
SCALE IN FEET
(Due #
\
Figure 2-1. Alternative 2
-------
TABLE 2-1
DESCRIPTION OF HORSEPEN CREEK WASTEWATER TRANSMISSION LINES
Line
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
Designation
Gravity
Gravity
Gravity
Gravity
Gravity
Gravity
Gravity
Gravity
Gravity
Gravity
Gravity
Force Main
Force Main
Design Flow
(CFS)
0.204
0.612
0.101
0.714
0.371
0.371
0.301
1.112
0.309
1.422
0.408
Diameter
(inches)
8
10
8
10
8
8
10
12
8
10
8
8
14
Length
(feet)
3800
10800
5000
5800
8800
840
4800
4400
5000
1000
900
8600
12000
No. of
Manholes
10
27
13
15
22
21
12
11
13
3
3
-------
To ensure that certain safeguards are adopted, the dis-
bursement of grant funds will be subject to the following condi-
tions :
(1) Potentially affected areas will be surveyed to
determine the presence of possible archaeo-
logical resources. This survey will be ac-
complished during the Step 2 process. The
survey plan and results will be subject to
approval by the North Carolina State Historic
Preservation Officer and State Archaeologist.
(2) If possible and complying with good engineer-
ing practices, interceptor lines should be
constructed completely out of or on the edges
of the floodplain. This condition should be
evaluated during Step 2.
(3) An erosion and sedimentation control plan
must be submitted to the Division of Natural
Resources and Community Development and EPA
for approval of its acceptability.
(4) The maintenance of a 30-foot vegetative buffer
between the edge of construction rights-of-way
and stream banks will be required where feasible.
(5) The immediate revegetation of interceptor
rights-of-way will be required.
Additional measures proposed to be taken at the local
level to mitigate adverse impacts of population growth upon water
quality are presented in Chapter 6.
10
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CHAPTER 3
ALTERNATIVES
11
-------
3.0 ALTERNATIVES
3.1 Description of Alternatives Considered
The agencies have developed five engineering alterna-
tives for providing sewer service to the existing and/or future
populations of the Horsepen Creek drainage basin. A "No Action"
alternative is included as one of these alternatives. The al-
ternatives were not intended to include every sewer line that
may be conceivably required. Rather, only the primary collectors,
lift stations, force mains, and interceptor necessary to service
the existing and expected future development were considered.
The alternatives to be evaluated are described below.
3.1.1 Configuration
Four alternative configurations, all of which can ser-
vice either existing or future development, plus the "No Action"
alternative for existing development, have been selected as pos-
sible configurations for the Horsepen Creek interceptor system.
3.1.1.1 Alternative 1
Alternative 1 recoirmends abandoning all lift stations
in the Horsepen Creek drainage basin and constructing an out-
fall interceptor from the Stage Coach Trail lift station along
Horsepen Creek to U.S. Highway 220. The Albert Pick lift sta-
tion will be maintained to transfer the Deep River tributary
wastewater to the Horsepen Creek collection system. New collec-
tors will be constructed from the abandoned lift stations to the
new Horsepen Creek interceptor to provide service to the exist-
ing developed areas. A new lift station and force main will be
constructed near U.S. Highway 220 to transfer wastewater from
the new Horsepen Creek interceptor to the North Buffalo Creek
12
-------
wastewater collection system. A schematic of Alternative 1 is
shown in Figure 3-1.
3.1.1.2 Alternative 2
Alternative 2 recommends abandoning all lift stations
in the Horsepen Creek drainage basin and constructing an outfall
interceptor from the Stage Coach Trail lift station along Horse-
pen Creek to U.S. Highway 220. A new force main will be con-
structed near Interstate 40 to transfer Deep River tributary
wastewater from the existing Albert Pick lift station to the
South Buffalo drainage basin and into a new outfall sewer which
discharges to the South Buffalo Creek collection system. New
collectors will be constructed from the abandoned lift stations
to the new Horsepen Creek interceptor to provide service to the
existing developed areas. A new lift station and force main will
be constructed near U.S. Highway 220 to transfer wastewater from
the new Horsepen Creek interceptor to the North Buffalo Creek
wastewater collection systems. A schematic of Alternative 2 is
shown in Figure 3-2.
3.1.1.3 Alternative 3
Alternative 3 recommends abandoning all lift stations
in Horsepen Creek drainage basin except the Stage Coach Trail
and Wagon Wheel lift stations. The Stage Coach Trail lift station
will be maintained to transfer wastewater to the South Buffalo
Creek collection system. The Albert Pick lift station will be
maintained to transfer the Deep River tributary wastewater to
the existing Stage Coach Trail collection system as currently
practiced. A new Horsepen Creek interceptor will be constructed
from near the intersection of Fleming Road and New Garden Road
to and along Horsepen Creek to U.S. Highway 220. New collectors
will be constructed from the abandoned lift station to the new
Horsepen Creek interceptor to provide service to the existing
13
-------
FORCE MAItl
FROM BRUSH
CREEK O/F
ORDINAL 12
TO NORTH
BUFFALO O/F
TO NORTH
BUFFALO O/F
LEGEND:
MAJOR ROAD
DRAINAGE BOUNDARY
- SANITARY SEWER SERVICE AREA
LIFT STATION
*- FORCE MAIN
»- GRAVITY SEWER
0 4000
SCALE IN FEET
(Line //
DEEP RIVER
BASIN
Figure 3.1. Alternative 1
-------
FORCE M«N
FROM BRUSH
CHEEK 0/F
.. TO NORTH
"" BUFFALO OIF
NEW PUMP$p
STATION
8
* ALBERT
PICK
DEEP RIVER
BASIN
Figure 3-2. Alternative 2
-------
Horsepen Creek interceptor to provide service to the existing
developed areas. A new lift station and force main will be con-
structed near U.S. Highway 220 to transfer wastewater from the
new Horsepen Creek interceptor to the North Buffalo Creek waste-
water collection system. A schematic of Alternative 3 is shown
in Figure 3-3.
3.1.1.4 Alternative 4
Alternative 4 recommends abandoning all lift stations
in Horsepen Creek basin except the Stage Coach Trail and Wagon
Wheel lift stations. The Stage Coach Trail lift station will
be maintained to transfer wastewater to the South Buffalo Creek
collection system. A new force main will be constructed near
Interstate 40 to transfer the Deep River tributary wastewater
from the existing Albert Pick lift station to the South Buffalo
drainage basin and into a new outfall sewer which discharges to
the South Buffalo Creek collection system. A new Horsepen Creek
interceptor will be constructed from near the intersection of
Fleming Road and New Garden Road to and along Horsepen Creek to
U.S. Highway 220. New collectors will be constructed from the
abandoned lift stations to the new Horsepen Creek interceptor
to provide service to existing developed areas. A new lift
station and force main will be constructed near U.S. Highway 220
to transfer wastewater from the new Horsepen Creek interceptor
to the North Buffalo Creek wastewater collection system. A
schematic of Alternative 4 is shown in Figure 3-4.
3.1.1.5 Alternative 5 - No Action
The existing Horsepen Creek wastewater collection sys-
tem will be maintained and operated as currently practiced. Any
new wastewater sources in excess of the capacity of the existing
facilities must be accommodated by septic tank systems. A sche-
matic of the existing facilities is shown in Figure 3-5.
16
-------
FORCE MAIN
FROM BRUSH
CHEEK _O'£
j-TO NORTH
BUFFALO O/F
TO NORTH
BUFFALO O/F
LEGEND:
MAJOR ROAD
DRAINAGE BOUNDARY
" SANITARY SEWER SERVICE AREA
LIFT STATION
» > FORCE MAIN
- GRAVITY SEWER
0 4000
SCALE IN FEET
II
(Line #
DEEP RIVER
BASIN
Figure 3-3. Alternative 3
-------
00
TO NORTH
BUFFALO 0/F
FORCE MAN
FROM BRUSH
CREEK O/F
*-i
LEGEND:
MAJOR ROAD
DRAINAGE BOUNDARY
SANITARY SEWER SERVICE AREA
LIFT STATION
FORCE MAIN
* *- GRAVITY SEWER
0 4000
SCALE IN FEET
(Line #---»
DEEP RIVER
BASIN
Figure 3-4. Alternative 4
-------
VO
FORCE MNN
FROM BRUSH
CREEK O/F"
)INAL '2
. TO NORTH
BUFFALO O'F
V
TO NORTH
BUFFALO O/F
LEGEND:
MAJOR ROAD
DRAINAGE BOUNDARY
SANITARY SEWER SERVICE AREA
LIFT STATION
-* FORCE MAIN
-- QRAVITY SEWER
0 4OOO
SCALE IN FEET
Figure 3-5. Existing Facilities (No Action Alternative)
-------
3.1.1.6 Alternative 6 - Modified Ho Action
A new force main will be constructed near Interstate
40 to transfer the Deep River tributary wastewater from the
existing Albert Pick lift station to the South Buffalo drainage
basin and into a new outfall sewer which discharges to the South
Buffalo Creek collection system. The existing Horsepen Creek
collection system will be otherwise maintained and operated in
its current configuration. This alternative was developed
through the Citizens Advisory Committee Process. A schematic
of Alternative 6 is shown in Figure 3-6.
3.1.2 Collection Line Sizes
The collection lines were sized by a systematic,
consistent methodology. The basic procedure followed is out-
lined below.
(1) Calculate per capita flow contribution. The
future population of the Horsepen Creek basin
is projected to be 18,700 persons with an esti-
mated sewage flow of 1.3 million gallons per
day (MGD). Thus, 18,700/1,300,000 = 70 gallons
per capita per day was assumed to be the average
flow contribution for residents in the basin.
(2) Divide basin into subbasin service areas.
The basin was divided into seven subbasins
(see Figure 3-6) according to existing sewer
service.
20
-------
FORCE WIN
FROM BRUSH
CREEK
TO NORTH
BUFFALO O/F
TO NORTH
BUFFALO OIF
SOUTH BUFFALO O/F
Figure 3-6. Alternative 6 (Modified No Action)
-------
(3) Disaggregate existing population. The existing
population of 8,080 persons was disaggregated
by subbasin according to existing land use
patterns. Residential areas were assumed to
have a uniform population density, and the exist-
ing population was divided accordingly.
(4) Calculate capacity of existing sewerage system.
All existing sewer lines in the basin were
evaluated for flow capacity. The Hazen-Williams
formula was employed. Design capacity of gravity
sewers was calculated with the lines flowing
two-thirds full. The formula was: Q = 1.32
CRo.6, gu.si A> where Q^ = design flow. s =
slope (determined from 7l; ' U.S.G.S. quads):
at two-thirds full, A = 0.5594D2 and R =
0.2914D, where D = inside pipe diameter in
feet; and C = 100. A peaking factor of 2
x average flow = Q was used. Force main
capacity was calculated using the Hazen-
Williams alignment chart (nomograph) with
the pipes flowing full and a peaking factor
of 2.4 x average flow. The results of these
calculations showed that existing lines are
extremely over-designed, and all lines in
the basin are running far below capacity.
(6) Estimate future wastewater flows. Future
growth will occur in the unshaded areas of
Figure 3-7. These areas exclude those parts
of the basin that cannot (or should not) ac-
commodate growth. The non-growth areas in-
clude current residential areas (both sewered
and non-sewered), industrial areas, and environ-
mentally sensitive areas (see Figure 11-21 of
22
-------
E = 0.129
F = 0.681
0 2000 4000
SCALE IN FEET
i£i;^'
E=0.198
F=0.35B
FLOWS (MGD):
AREAS FOR FUTURE POPULATION GROWTH E = estimated existing flow
ENVIRONMENTALLY SENSITIVE r F = Pr°Jected future flow
CURRENTLY DEVELOPED
Figure 3-7. Future Growth Areas in the Horsepen Creek
and Wastewater Flows by Subbasin
O 9
02-2659-1
-------
the Greensboro DEIS). The area available in
each of the seven subbasins for future residen-
tial development was derived by planimetering.
Population increases were allocated proportionately
according to the following formula:
Population Increase in Subbasin = Subbasin Areas (acres)
Total Projected Population Total Area Available
Increase (=10,620) for Future Growth
(=3,107 acres)
This, of course, assumes uniform distribution of future popula-
tion. Flow estimates from each of these areas were made as in
Step 4.
(7) Calculate additional facilities' needs. Pipe
sizes and lift station requirements were de-
termined for all four engineering alternatives
under both existing and future flow regimes.
The Hazen-Williams formula was employed as
described in Step 5. In the largest subbasin,
where several lines traverse the future growth
areas, flow from that subbasin was apportioned
among the various lines.
The results of this analysis produced the design sizes
for the sewer lines segments shown in Table 3-1
3.2 Environmental Evaluation of Alternatives
Agency guidelines require that the proposed action be
the cost-effective option selected from a group of environmentally
acceptable alternatives. To the extent practicable, the cost-
effective analysis should maximize environmental benefits while
24
-------
TABLE 3-1
DESIGN SIZES FOR SEWER LINE SEGMENTS (Diameter in ii
Alternative #
Line #
1
2
3
4
5
6
7
8
9
10
11
12
13
IE
14
20
8
20
8
8
10
20
8
-
8
12
IF
14*
22*
8
24*
8
8
12
26*
8
-
10
14*
2E
8
10
8
10
8
8
10
12
8
10
8
8
14
2F
8
14
8
16
8
8
12
20
8
10
10
12
14
3E
-
-
8
8
8
8
10
10
8
-
-
8
3F
-
-
8
10
8
8
12
16
8
-
-
10
4E
-
-
8
8
8
8
10
10
8
10
-
8
14
4F
-
-
8
10
8
8
12
16
8
10
-
10
14
5 6
-
-
-
-
-
-
-
-
-
- 10
-
-
- 14
*Estimates based on ratio of 2E:2F
Line
Length
(feet)
3,800
10,800
5,000
5,800
8,800
840
4,800
4,400
5,000
1,000
900
8,600
12,000
25
-------
minimizing costs and environmental detriments. At the minimum,
however, the cost-effective option must not possess over-riding
environmental problems. It is within this context that the
analysis of alternatives for the Horsepen Interceptor has been
conducted. The ultimate goal of this analysis is primarily to
distinguish environmentally acceptable options (i.e., those free
of over-riding adverse impacts), and secondarily to suggest the
degree of their environmental acceptability.
The alternatives analysis is couched in terms of quan-
titative and qualitative effects on the air, land, water, bio-
logical, and cultural resources of the Horsepen Creek vicinity.
Besides the No-Action alternative, the alternatives may be cate-
gorized as to whether they serve only the "Existing" conditions
(.Alternatives IE, 2E, 3E, and 4E) or the projected "Future"
development (Alternatives IF, 2F, 3F, and 4F). It should also
be recognized that all new alternative configurations of the sewer-
age system have a large common component, i.e., the lower portion
of the basin (approximately, downstream of New Garden Road).
3.2.1 Air Quality
None of the area is currently a non-attainment area
for any criteria pollutants. Nevertheless, the differences
in air quality impact associated with the various alternatives
must be addressed on a pollutant-specific basis. Further, at
the level of analysis available for this study, air quality
considerations revolve around the three generic types of al-
ternatives (Existing, Future, and No Action), rather than the
configurations of the sewerage alternatives.
On the basis of monitoring data and national-level
considerations, secondary impacts to air quality appear of
more concern than short-term primary effects related to
26
-------
construction. Specifically, total suspended particulates and
photochemical oxidant precursors, such as hydrocarbons and
nitrogen oxides, are recognized generally as sensitive to
population growth.
The area quality maintenance analysis performed for
the Greensboro AQMA demonstrated that population density is a
good indicator of TSP levels. This study encompassed too large
an area to be useful for specifically analyzing differences in
alternatives for the Horsepen Creek interceptor. But generally,
an alternative that results in higher population density will
be more adverse with respect to TSP. Hence, any "Future"-type
alternative will increase TSP levels in the area more than
"Existing" types or "No Action". While recent trends are en-
couraging, TSP levels that have been monitored at representative
locations are already high, and provisions of Prevention of
Significant Air Quality Deterioration with respect to TSP con-
ceivably could be limiting to industrial growth in some areas.
It should be recognized that a trade-off exists: particulate
emissions from agricultural and other rural activities will be
replaced by urban particulate emissions. Urban-area particulates
are largely man-made and tend to be more hazardous to human
health and welfare than those from natural origins.
Growth in the Horsepen Creek basin and the rest of
Guilford County may also cause increases in photochemical oxi-
dant levels. Since this pollutant is not currently monitored,
this is an unknown problem. But EPA has acknowledged the
validity of studies showing that any urban area over 200,000
population should be a candidate for oxidant precursor emissions
reductions. Such reductions may ultimately be required to pre-
vent local and regional oxidant problems. However, the effects
of oxidants are apparently not sensitive to the exact geo-
graphical distribution of the population. Therefore, all
27
-------
alternatives would have essentially the same impact with respect
to oxidant levels.
The air quality impacts of population growth due to
wastewater facility expansions must be analyzed pursuant to
Section 316 of the 1977 Clean Air Act Amendments. Revisions
to state implementation plans are to include consideration of
these impacts. At this time it is unclear if and how these
revisions would affect the analysis of the available alternatives,
since no regulations implementing the Amendments have been pro-
mulgated. It should be remembered, however, that growth in
Horsepen Creek is only part of the projected growth for the
Greensboro area, so the incremental air quality impact really
cannot be avoided, only minimized by the type of development en-
couraged .
Odor is also a gaseous air-borne pollutant. Those
alternatives that provide transmission of Deep River tributary
wastewater directly to the South Buffalo basin (2E, 2F, 4E, 4F,,
and 6) will likely have very slow moving wastewater in the upper
portion of Horsepen basin because of the grossly oversized exist-
ing sewer lines there. This condition, which will be extreme
during dry weather flows under alternatives 2E, 4E, and 6, may
result in periodic odors of septic sewage from manholes and wet
wells, unless the lines are regularly flushed out. The efficacy
of this may be limited by the capacity of the downstream lift
station to convey the water to the South Buffalo plant for treat-
ment. In aggregate, this mitigating measure is a substantial
waste of valuable water and energy resources.
3.2.2 Land Resources
The major limitation to development is the poor septic
tank suitability of the soils in the basin. This will make proper
28
-------
site evaluation, drainfield design, and maintenance practices more
critical than soil series (types) in determining septic tank
feasibility. Generally, however, the upland soil series on the
margin of the basin and the soils throughout the lower basin
are expected to perform somewhat better than the soils elsewhere
in the basin (see Figure 4-3). The primary impact of malfunction-
ing septic tanks would probably be surface-water quality degrada-
tion, as opposed to ground water effects, due to the rather large
thickness of impermeable rock material in this area, and due to
the impermeable subsoils that would tend to conduct poorly re-
novated effluent laterally.
The central (non-upland) part of the upper basin in-
cludes large areas underlain by fairly erodible soil. Some
alternatives (IE, IF, 2E, 2F) have considerably more rights-
of-way that cross these erodible areas and that are near streams
than other alternatives. (All of these four alternatives re-
quire constructing an interceptor along virtually the entire
length of Horsepen Creek). These considerations suggest that
degradation of aquatic habitat, currently of high quality, can
readily occur unless sediment control is diligently practiced.
While substantial amounts of chiefly non-settleable (colloidal)
solids are currently delivered to streams, construction may pro-
mote delivery of large quantities of settleable solids. Stream
siltation and the substrate instability may produce undesirable
consequences on the aquatic flora and fauna of Horsepen Creek
and Lake Brandt.
A cumulative impact of all alternatives will be the
urbanization of prime farmland soils. Most of the acreage in the
Horsepen basin is in the Cecil, Mecklenburg, Madison, and Enon soil
series, all of which have phases that are considered prime farm-
land soils. Most agriculture presently exists in the southwestern
portion of the basin. A substantial portion of the basin under-
lain by prime farmland soils is now forest, and will probably
29
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never become farmland, inasmuch as its economic value for suburban
development now far exceeds its agricultural potential. Unless
outright prohibition on development occurs, ultimately (beyond
the design period) the entire basin will urbanize, whether on
sewers, septic tanks, small lift stations, or a mixture of the
three. From this ultimate perspective, no differences exist among
the alternatives. Providing efficient sewerage probably only
hastens the ultimate condition.
3.2.3 Water Resources
The Horsepen basin has an under-developed ground-water
supply. High-quality ground water is readily available to in-
dividual users throughout the basin. Individual domestic users
(or groups of users) will be able to exploit the ground-water
resources and ease regional water-supply problems that are just
now becoming apparent. Despite the poor permeability of the
soils and the large thickness of saprolite, the concomitant use
of ground water within the fractured-rock aquifer and of septic
tanks for wastewater treatment would be a source of concern.
The integrity of the ground-water supply in a local area could
not be guaranteed in such a hydrogeologic setting with septic
tank use.
As the Horsepen Creek basin drains to Lake Brandt,
the effects of existing and future development in the basin are
a source of concern. It is widely recognized that urbanization
will generally tend to promote increased runoff with substantially
impaired quality. For this reason, a special study of this pro-
blem was undertaken as part of the decision-making effort. The
study report is entitled "Investigation of Water Quality Impacts
Related to Development of the Horsepen Creek Basin, Guilford
County, North Carolina" (RA-R-507). The reader is referred to
this report for details concerning scope, methodologies, and
30
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results. The study concluded that if an interceptor is constructed
to serve the projected future population, subsequent intensive
development within the basin would significantly degrade the
water quality of Horsepen Creek and Lake Brandt. Increases in
eutrophication potential and heavy metals loading from urban run-
off would be the major effects.
If sewerage is provided for the existing population only,
future development will not be prevented, but will be forced to
utilize a combination of septic tanks and collectors/lift stations/
force mains (unless prohibited by City and County policy initia-
tives). Ultimate impacts to the watershed will be less (probably
significantly less) than if projected future development is ser-
viced by sewerage. Quite simply, the less intensive land use
of the non-sewered future population will minimize the concen-
trations of pollutants generated in urban runoff. This less in-
tensive land use is guaranteed by restrictions on minimum lot
size with septic tanks, the likelihood of areas judged unsuitable
(and non-permittable) for septic tanks, and the inherent land-
use inefficiencies in completely suburbanizing an area with a
mosaic mixture of various sewered and non-sewered area. In ad-
dition, lack of sewerage will tend to impede the timing of de-
velopment;, even in this relatively attractive area. Therefore
additional valuable time may be provided to obtain a water supply
of higher integrity. In summary, the water quality impacts to
Lake Brandt and Horsepen Creek will be minimized (but far from
avoided) by either "No Action" or an alternative that sewers
only the existing population.
Strict enforcement of the County Health Department's
comprehensive septic tank ordinance will minimize primary surface-
water impacts from improperly functioning septic tanks. It should
be recognized however that most of the. renovated effluent will
31
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ultimately discharge to surface streams as base flow and, there-
fore, to Lake Brandt. Water quality impacts due to renovated
effluent, however, will be minor compared to the hazards posed
by urban runoff, based on the results of the water-quality study.
As a result of this decision-making process, all alterna-
tives (including "No Action") will provide an impetus toward find-
ing alternative water supplies for the City of Greensboro; none
of the options preclude options identified in the Greensboro
treatment facilities EIS.
The probabilities of adverse water quality (and aquatic
biota) effects due to exfiltration, leakage, and surcharging are
considered to be minimized by reducing the number of lift stations
and force mains and/or by replacing such facilities by ones with
newer materials and more advanced design. In this regard, Al-
ternatives IE, IF, 2E, and 2F are most beneficial, in that they
eliminate all but one lift station and force main in the Horsepen
Creek basin. The No Action alternative and to a lesser extent,
the Modified No Action alternative, on the other hand are consi-
dered long-term threats to the water quality of Horsepen Creek
and other streams in that they maintain the inefficient network
of myriad lift stations and force mains. The present system's
capacity in the Horsepen basin is sufficient for wastewater
transmission there, but City records indicate that the Horsepen
wastewater that is pumped to the South Buffalo basin occasionally
surcharges the smaller collectors in that basin. While not in
the Horsepen basin, this surcharging produces undesireable health-
related effects on drainageways in a populated area. (Alternative
6, Modified No Action, would mitigate this effect somewhat by
removing Deep River wastewater flow from the Horsepen Creek basin)
In addition, while lift station failure and by-passing occurs
only very infrequently, the larger number of stations translates
32
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to a much higher probability of such occurrence. Even with pre-
ventive maintenance, this increase in failure frequency cannot
be circumvented.
Since Alternatives IF and 3F would include larger base
flows (from a larger service population and transfer of Deep
River basin tributary wastewater), the potential for an adverse
impact due to a leak or pump station overflow is somewhat larger
for these alternatives than for the other alternatives. In
actuality, the difference in these flows is small enough such
that this difference in potential harm among the alternatives is
probably not significant.
In all alternatives there will be a relatively strong
tendency to utilize that portion of the pipeline capacity re-
served for peak flows (or otherwise available due to the reali-
ties of pipeline sizing) for increasing the service population
beyond the design population. This will be particularly the case
with those which service only "Existing" conditions (IE, 2E, 3E,
and 4E) and with those (2F especially) that provide the most
extensive, efficient wastewater collection system. Without some
positive initiatives, this condition usually translates into a
large chance for system overloads after the design year. Such
overloads, in the form of surcharging and bypassing, can lead
to adverse public health effects, vector control problems, and
disruption of the aquatic ecosystem.
3.2.4 Biological Resources
Short-term biological impacts are largely proportional
to the length of the sewer lines, especially gravity sewers. The
following reference data are useful:
33
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58
71
43
56
13
,700
,700
,200
,200
0
,000
ft.
ft.
ft.
ft.
ft.
50
51
34
35
1
,100
,100
,600
,600
0
,000
ft.
ft.
ft.
ft.
ft.
101
123
74
97
0
22
acres
acres
acres
acres
acres
Length of Approximate
Length of All New Gravity Land
Alternative New Sewers Sewers Area Disturbed
IE, IF
2E, 2F
3E, 3F
4E, 4F
No Action (5)
Modified No
Action (6)
Because gravity sewers are laid along watercourses, they are
of concern with respect to both stream siltation and destruction
of the more critical riparian vegetation and bottomland habitat.
From an ecological perspective, terrestrial habitat disturbance
may not be significantly different between the alternatives, but
it may be a significant effect overall. Differences in stream
siltation among the alternatives are likely to be more signifi-
cant, especially since alternatives 1 and 2 are not only longer
but cross more erodible area.
Long-term biological impacts relate primarily to habi-
tat attrition/degradation by residential development. Differences
among the alternatives may be categorized according to whether
they are designed for "existing" or "future" types of development.
Ultimately, however, no alternative will prevent virtually
complete fragmentation of the natural habitat. Only the timing
of this destruction varies among the alternatives,
The principal long-term effect on aquatic biota in
Lake Brandt will be the hastened eutrophication of the lake,
due to increased light and, to a much lesser extent, nutrients.
Oxygen depletion and possibly even toxic loads of some trace
elements will be more stressful to aquatic biota of the reservoir.
34
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3.2.5 Cultural (Man-Made Resources)
All alternatives, except No Action, will have direct
effects due to construction activities and indirect effects
accompanying the use of the facilities. The alternatives are
evaluated here by discussing general impacts on the various
components of the man-made environment (e.g., demography, trans-
portation, etc.). The environmental trade-offs of each alter-
native are highlighted.
3.2.5.1 Demography and Economics
An underlying assumption in developing the alternatives
has been that 18,700 people will live in the Horsepen Creek basin
in 2000. This represents a growth of 10,620 from the 1975 popu-
lation of 8,080. This growth projection is a constant in this
analysis, regardless of the alternative. Furthermore, to project
the appropriate size sewer for the various subbasins within the
Horsepen Creek basin, it has been assumed that the population will
be dispersed uniformly in those undeveloped areas which are not
"environmentally sensitive." Based upon the assumptions being
employed, there is no difference between the alternatives with
respect to population size or distribution. Also, commercial
and industrial development should continue as projected regard-
less of the alternative selected. At this time it does not
appear that anyone will be displaced during emplacement of any
sewer lines.
The above conclusions actually concern only the in-
direct effects of facility operations. The direct effects of con-
struction on the economy will vary between alternatives because
of the cost. Obviously, "no action" will stimulate no economic
activity. However, even the $2.4 million of the most expensive
alternative is a relatively small stimulus to local economic ac-
tivity, and is not considered significant to regional economics.
35
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3.2.5.2 Land Use
The population increase projected for the Horsepen
Creek subbasin will cause significant land use change. Regard-
less of the alternative selected, more of the area will become
residential in use. Hence, forests and agricultural land in
the subbasin will decline in acreage, especially west of Horse-
pen Creek.
The major difference between the various alternatives
is in the density of development. The No Action and Modified
No Action alternatives will cause a considerable part of future
development to be on septic tanks. Assuming one-acre lots for
septic tank users, the entire subbasin could be developed by
the year 2000. Alternatives servicing existing population are
identical in this regard, although somewhat more intensive land
use than that of "No Action" is anticipated. In the No Action
alternative and quite probably in any alternative that services
only "existing" development, the resulting land use patterns
may increase pressure for development upon land considered to be
environmentally sensitive. Such land includes floodplains, air-
port noise and lake quality buffer zones, and areas with erodible
soils and slopes exceeding 15 percent. Sewerage provides a modi-
cum of de facto control for guiding growth away from such areas.
All alternatives servicing future population growth will
probably result in the development of a smaller percentage of the
total basin through the year 2000 because denser residential de-
velopment is probable. For instance, multi-family units are more
likely in the Horsepen Creek basin in areas where municipal sewage
treatment is available. Higher density development based upon
smaller lot size requirements and a growth of multi-family hous-
ing will not require the entire 3107 acres available through the
year 2000. For instance, an overall density of just six people
per acre would reduce the land required for residential develop-
ment to 1770 acres through the year 2000.
36
-------
Ultimately, however, the basin will be totally developed
under all the alternatives. The major difference will be the
density of this development. The full service alternatives will
allow a much higher density development pattern to occur in the
basin.
3.2.5.3 Community Services and Facilities
As the population of the Horsepen Creek basin increases,
certain services and facilities will have to be provided or ex-
tended in that area. Included would be schools, roads, utilities,
and so on. The only difference between the various alternatives
revolves around the increased cost of providing these services
to low density residential areas. The development costs asso-
ciated with low density development are significantly greater than
with higher density development. Hence, No Action must be looked
upon as more expensive to Guilford County. It is very important
to keep in mind the assumptions utilized in developing these al-
ternatives. The total population in the basin has been fixed.
3.2.5.4 Taxes and Budgeting
The total cost of those alternatives which require con-
struction funds is relatively small, especially compared to the
other Section 201 activities which have been proposed (EN-R-618).
Given the substantial increase in the tax base provided by the
higher income residential area of Horsepen Creek, any of the
Horsepen Creek alternatives would not signficantly adversely
affect local fiscal conditions. No Action would incur continuing
operational and maintenance costs, including replacement costs,
for the operation of the existing system of lift stations.
37
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3.2.5.5 Archaeological, Cultural, Historical, and Recreational
Resources
The precise routes for the sewage lines have not been
firmly established. Hence, it is difficult to assess the poten-
tial impact on these resources. An historical and archaeological
survey will be conducted on the final routes and the results
will be reviewed by the State Historic Preservation Office and
State Archaeologist if an alternative other than "No Action" is
selected. (No archaeological resources are known along any route
at this time.)
A preliminary review of existing inventories for the
Horsepen Creek basin does not indicate the existence of histori-
cal resources in that area which will be affected by construction
activities. The recreational resources of the area will not be
affected by construction activities. They may experience more
use as the population of the area grows. However, this growth is
constant regardless of the alternative selected.
3.2.6 Summary
The results of this alternatives evaluation show that
water quality and land use impacts are the most significant to
this project. Selection of the No Action or Modified No Action
alternatives would encourage low density development throughout
the basin. The existing service alternatives would also generally
tend to encourage low density development with some higher density
development connected to the new sewer line. The future service
alternatives will provide for much higher development densities
throughout the basin. In the short term, this development will
probably be concentrated adjacent to those areas that are currently
developed. Ultimately, development will occur throughout the
basin .
38
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The less intensive land use densities of existing ser-
vice alternatives will minimize the concentration of pollutants
generated in urban runoff. These alternatives will have a signi-
ficantly smaller potential adverse impact to water quality in
Lake Brandt than the future service alternatives with their sub-
stantially higher land use densities.
Other potential adverse impacts to water quality could
result from the existing system of lift stations and septic tank
failures. The No Action and Modified No Action alternatives
would not alleviate these potential hazards. Alternatives IE
and 2E would do the best job in this regard by eliminating all
but one lift station. Alternative 2E is considered the most
environmentally acceptable alternative since it alleviates the
existing problems with the smallest encouragement of high density
development.
3.3 Cost Analysis of Alternatives
The engineering alternatives were analyzed based on
the estimated existing and future distribution of population in
the Horsepen Creek basin as described in Section 3.1. The es-
timated future sewage flow of 1.3 million gallons per day (MGD)
from a projected population of 18,700 persons was used as a
basis for pipe sizing. All areas not currently developed or
environmentally sensitive were assumed to have a uniform dis-
tribution of future inhabitants.
It was assumed that all areas currently serviced by
septic tanks would be converted to sanitary sewers. An evalua-
tion of existing line capacities showed over-design far in ex-
cess of future needs. Therefore, only the construction of the
new lines and pump station as described in Section 3.1 were
considered in the cost analysis.
39
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Gravity sewers were costed on the basis of $2.00/inch
diameter/foot of length plus $250/mile operation and maintenance
cost per year (O&M). Force mains were costed at $1.50/inch
diameter/foot of length plus $250/mile O&M. Lift stations were
sized using a peaking factor of 2.4 x average inflow. Capital
and O&M costs were derived from Stanley Consultants' cost cur-
ves, A trend factor of 1.5 was applied to construction costs
to bring numbers into current dollars. Present value was cal-
culated on the basis of 6 5/8 percent A.P.R. over a 20-year
design period. Useful lives were as follows: pipes = 40 years,
lift station structures (1/2 of construction cost) = 40 years,
lift station pumps (1/2 of construction cost) = 20 years.
Retained existing lift stations were replaced based on their
construction date, and salvage value was calculated as of the
year 2000. Existing gravity sewers which will remain in use
regardless of which alternative is selected were not included
in the present value cost analysis.
The costs of the various alternatives are presented in
Table 3-3.
3.4 Selection of Proposed Action
Alternative 2E as described above has been selected
as the proposed action based upon the environmental analysis
as summarized in Section 3.2.6. This alternative is deemed to
be the most cost-effective alternative which is environmentally
satisfactory.
40
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TABLE 3-3
COST OF ALTERNATIVES
Alternative
IE
IF
2E
2F
3E
3F
4E
4F
5
6
Capital
($ million)
1.82
2.40
1.38
1.83
1.08
1.20
1.19
1.30
0.34
O&M
($ thousand/year)
9.5
11.3
8.5
10.1
15.5
19.5
15.4
18.6
26.5
Net Present
($ million)
1.68
2.23
1.28
1.70
0.98
1.19
1.13
1.32
0.47
Worth
(rank)
7
9
5
8
2
4
3
6
1
-
41
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CHAPTER 4
DESCRIPTION OF THE AFFECTED AREA
42
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4.0 DESCRIPTION OF THE AFFECTED AREA
For the purposes of this Environmental Impact Statement
(EIS) the study area includes the Horsepen Creek basin as shown
in Figure 4-1. The total environment is divided into natural
and man-made aspects and each, while interactive, is discussed
separately. Components of the existing environment for which
no significant impacts are expected as a result of the proposed
action (climate, air quality, noise, topography, geology, and
elements of the man-made environment) are summarized in the fol-
lowing section. Supporting documentation concerning these areas
is provided in the Technical Reference Document (RA-R-406) and
the Greensboro EIS (EN-R-687). A more complete discussion of
existing conditions is provided here for the soils, water quality,
and biology of the Horsepen Creek basin, which are subject to the
most significant impacts.
4.1 Environmental Context
Greensboro has a temperate climate characterized by
relatively short, mild winters and long, hot summers. Pre-
cipitation is abundant. North-northeasterly and south-southeasterly
winds prevail during the year as a result of high pressure systems
which progress across the eastern United States.
Presently, the general air quality of the study area is
good with respect to the criteria pollutants. Guilford County
is designated an Air Quality Maintenance Area for suspended parti-
culates. This designation has implications regarding the future
growth of suspended particulate levels. Air pollutant emissions
in the study area are typical of a moderately industrialized urban
region. No community-wide odor problems exist in the study area.
43
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ROCKINGHAM CO
Figure 4-1. Horsepen Creek Study Area
-------
The Greensboro area has a noise climate typical of simi-
lar metropolitan areas in the United States. Residential areas
are characterized by low to moderate levels permitting, in most
areas, pursuit of outdoor activities without interference from in-
truding noise. Zones of higher noise level are near major traffic
arteries and the airport.
The topography of Guilford County is typical of the
Piedmont Plateau physiographic province in that it is gently rol-
ling in the uplands and somewhat more rugged near the major streams.
The bedrock of the county consists of igneous and metamorphic rocks
that are also typical of the Piedmont province. The bedrock is
overlain by a thick mantle of saprolite (soft, weathered bedrock)
in most of the county. The most important geologic processes are
ground-water recharge and flooding.
Because of the geologic setting of Guilford County, major
regional aquifers do not exist. However, shallow, low-productivity
water-table aquifers are present, which serve as important water
sources in rural areas. The ground water of these aquifers occurs
in pore spaces in the saprolite and in fractures in the underlying
bedrock. Recharge to the aquifers occurs in the uplands, and dis-
charge is to wells or as baseflow to the streams. The total ground
water available in the county is estimated to be about 150 MGD, but
only approximately 11 MGD is presently being used. Ground-water
quality is generally good, except for a high iron content in some
areas. Ground-water quality problems from septic tanks have been
reported in the county.
The Horsepen Creek study area had 8,080 people in 1975
and is projected to have 18,700 in 2000. The land use pattern is
a mixture of low-density suburban development along the eastern
boundary, commercial and industrial in the southwestern portion,
and agricultural and forest land along the western boundary.
45
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The Greensboro area economy has grown since 1970 with
20,000 jobs created in Guilford County from 1970 to 1974. Unem-
ployment has been low in recent years (normally under 4 percent),
Manufacturing dominates the employment structure with textile
employment being conspicuously important. Employment in manu-
facturing sectors such as wholesale/retail trade and services
has grown in recent years.
Greensboro and Guilford County are providing police
and fire protection, health care, education, waste disposal,
libraries, and other public services. Greensboro and Guilford
County are financially sound governments paying for their needs
with very little bonding required.
The Guilford County area has a rich cultural heritage
which is being enhanced and protected. Nationa1 Re g i s t e r his-
toric sites are located in Greensboro and many buildings and
areas of historic value have been identified. Also, the area
may have archaeological resources, but they are not well known
at this time. Recreational resources are scattered throughout
the city and county.
As a focal point of North Carolina highways, Greens-
boro's major thoroughfares are heavily used. Thoroughfares are
planned to relieve excess traffic loads as they develop, espec-
ially in peripheral areas.
Duke Power Company will be able to meet the area's
energy requirements through the year 2000 as long as coal and
nuclear fuels are available. No major natural resources are
being extracted in the study area.
46
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4.2 Areas of Significant Impact
4.2.1 Soils
The soils of the Horsepen Creek watershed are typical
soils of the Piedmont uplands. The surface horizons are generally
less than one foot in thickness and are composed of brown loam or
sandy loam. The subsoils consist of red or yellow clay and range
from 25 to 50 inches in thickness. Most of the upland soils are
classed in the Alfisol or Ultisol order of the modern soil clas-
sification system (US-517), which indicates that the soils are
highly weathered and leached and have developed over a long per-
iod of time. The clay content of the topsoil of these soils has
washed down (eluviated) into the subsoil, giving rise to the loamy
texture of the topsoil and the clayey subsoil texture. Because
of the uniformity of bedrock composition (mostly igneous and meta-
morphic silicate rocks) and the predominance of the time and cli-
mate factors in the formation of the soils, the type of parent
material does not have a major effect on the soil characteristics.
The alluvial soils in the streambeds are less well developed (in
terms of horizonation) and are thus classed as Inceptisols or
Entisols.
A soil map of the Horsepen Creek basin is presented
in Figure 4-2. The map units shown are soil series, which
are the basic mapping units of the USDA Soil Conservation
Service. A description of the soil series is given in Table 4-1.
Examination of Figure 4-2 shows that the primary ijoil units on
the uplands are the Cecil and Mecklenburg series, with the Coron-
aca, Madison, and Enon series taking in most of the remainder of
the upland area. The narrow bottomlands along Horsepen Creek
and its tributaries have typical floodplain soils that include
primarily the Chewacla and Congaree series with lesser areas
covered by the Wehadkee series. The remainder of the soil units
47
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00
Ap
Ce
Ch
Cg
Cr
En
He
Ir
Ma
Me
Va
We
Wi
G
U
Appling
Cecil
Chewacla
Congaree
Coronaca
Enon
Helena
Iredell
Madison
Mecklenburg
Vance
Wehadkee
Wilkes
Gullied Land
Urban Area
0 2000 4000
SCALE IN FEET
SOURCE: US 562
Figure 4-2. Soil Series of the Horsepen Creek Basin
-------
TABLE 4-1
DESCRIPTION OF SOIL SERIES IN HORSEPEN CREEK BASIN
Series
DescriptIon
Series
Description
Appling
Cecil
Chewacla
Congaree
Coronaca
Enon
Helena
The Appling series consists of well drained,
moderately permeable soils that formed in
residuum weathered from acid igneous and
metamorphic rocks. These soils are on broad
ridges and long, narrow side slopes. Slopes
are 2 to 10 percent.
The Cecil series consists of well drained,
moderately permeable soils that formed in
residuum weathered from acid igneous and
metamorphic rocks. These soils are on
broad to very broad, smooth ridges and on
long, narrow side slopes. Slopes are 2 to
15 percent.
The Chewacla series consists of somewhat
poorly drained, moderately permeable soils
that formed in recent alluvium. These
soils are in long, flat areas parallel
to the major streams on the floodplains.
Slopes are 0 to 2 percent.
The Congaree series consists of well
drained, moderately permeable soils that
formed in loamy alluvium. These soils
are on long, narrow floodplains. Slopes
are 0 to 2 percent.
The Coronaca series consists of well
drained, moderately permeable soils that
formed in material weathered from horn-
blende gneiss, gabbro, and dlorite. These
soils are on broad, smooth interstream
divides. Slopes are 2 to 10 percent.
The Enon ser les consists of well drained,
slowly permeable soils that formed in
residuum weathered from dark colored
rocks such as diorite, gabbro, horn-
blende schist, or mixed acidic and basic
rocks. These soils are on broad, smooth
intprstream divides and long, narrow
side slopes. Slopes are 2 to 15 percent
The Helena series consists of moderately
well drained, slowly permeable soils that
formed in a mixture of material weathered
from acidic and basic crystalline rocks
such as nplitic granite or granite gneiss
that is cut by dikes of gabbro and diorite.
These soils are on long, narrow side slopes.
Slopes are 0 to 10 percent.
Iredell
Madison
Mecklenburg
Vance
Wehadkee
Wilkes
The Iredell series consists of moderately
well drained, slowly permeable soils that
formed in residinim weathered from diorite,
gabbro schist, and other rocks high in con-
tent of ferromagneslan minerals. These
soils are on flats, in concave areas, and
around the heads of intermittent drainage-
ways. Slopes are 0 to 4 percent.
The Madison series consists of well drained,
moderately permeable soils that formed in
residuum weathered from acid micaceous meta-
morphic rock. These soils are on fairly
narrow ridges and long, fairly narrow side
slopes. Slopes are 2 to 35 percent.
The Mecklenburg series consists of well
drained, slowly permeable soils that formed
in material weathered from dark colored
bacic rocks such as diorite, gabbro, and
hornblende schist. These soils are on
broad, smooth interstream divides and long,
narrow side slopes. Slopes are 2 to 10
percent.
The Vance series consists of well drained,
slowly permeable soils that formed in
residuum weathered from acid crystalline
rocks, primarily aplitic granite. These
soils are on narrow ridges and long narrow
side slopes. Slopes are 2 to 15 percent.
The Wehadkee series consists of poorly
drained, moderately permeable soils that
Formed in alluvium derived from schist,
gneiss, granite, phyllite, and other meta-
morphic and igneous rocks. These soils
are on stream floodpialns. Slopes are
0 to 1 percent.
The Wilkes series consists of well drained,
moderately slowly permeable soils that
formed in residuum weathered from diorite,
hornblende schist, and related rocks that
are moderately high in content of ferro-
magnesian minerals or that formed in a mix-
ture of acidic and basic rocks. These soils
are on side slopes that generally border
drainageways. Slopes are 6 to 65 percent.
Source: US-A-1086
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in the basin (Appling, Helena, Iredell, Vance, and Wilkes series)
are minor upland soils.
The most significant properties of each soil series
are shown in Table 4-2. Also shown in the table are the suita-
bility of each soil series for installation of septic tanks and
drainfields. These interpretations are based on ratings of the
soils by the Soil Conservation Service for this use (US-562).
Most of the soil units present in the Horsepen Creek basin are
not well suited for septic tank use. The upland soils are poorly
suited primarily because of the low permeability of the clayey
subsoil. The lowland soils are unsuited for septic tank use be-
cause they are saturated or frequently flooded.
The interpretations of the soil series map units in
terms of their suitability for septic tank use can be used in
conjunction with the soil map in Figure 4-2 to formulate a sep-
tic tank suitability map. This map, which is shown in Figure
4-3, shows quite graphically the relative suitability of the
soils for septic tank use. Most of the soils of the area have
been given a "fair to poor" rating. These soils occur over a
large part of the upland portion of the basin in a wide area
adjoining the basin boundaries. The central part of the basin,
including the creeks, is classified in the "poor" suitability
category. The best-rated soils, which are given a only a "fair"
rating, occur in a smaller part of the basin, primarily in an
upland area south of Horsepen Creek.
In summary, the soils of the Horsepen Creek basin are
generally not well suited for septic tank and drainfield installa-
tions. Locally, areas where septic tanks will perform adequately
may be found. Such areas generally cannot be discerned without
site-specific testing. The overall poor suitability of soils in
50
-------
TABLE 4-2
Series
Appllng
Cecil
Cheuacla
Congaree
Coronaca
Enon
Helena
Iredell
Madison
Mecklenburg
Vance
Vehadkeee
Hilkes
Map
Symbol
Ap
Ce
Ch
Cg
Cr
En
He
Ir
Ma
Me
Va
We
Wi
Hydirologic
Group
PHYSICAL
Erodibility
Factors
K T
.32 4
.32 4
__
.24 5
.37 4
.37 3
.43 3
.32 4
.37 4
.37 3
.28 2
PROPERTIES
Septic Tank
Suitability
Fair
Fair
to
Poor
Poor
Poor
Fair
Poor
Poor
Poor
Fair
to
Poor
Poor
to
Fair
Poor
Poor
Poor
OF SOIL
Horizon
(inches)
0-10
10-54
54-60
0-7
7-50
50-75
0-14
14-58
0-8
8-38
38-62
0-6
6-80
0-7
7-34
34-50+
0-12
12-19
19-46
46-60
0-7
7-24
24-27
27-40
0-7
7-30
30-44
0-6
6-36
36-48
0-6
6-40
40-60
0-8
8-40
40-50
0-6
6-13
30-48
SERIES
*USDA
Class
cosl, si, fsl
ct sc
scl, cl, si
si, fsl, 1
c
cl, 1
fsl, 1, si
si, 1, cl
1
1
scl
scl, cl, 1
c
fsl, si
c
cl
si, fsl
sc;., ci
c, sc
si
si
c
1
si
grfsl
c to cl
si
1, sil, 3l
c
cl, 1
cosl, si, fsl
c, sc
1, scl, cl
fsl, 1, si
1, sc
si
si, 1
cl, c, scl
si, 1
Permeability
(in/hr)
2.0 - 6.3
0.63 - 2.0
0.63 - 2.0
2.0 - 6.3
0.63 - 2.0
0.63 - 2.0
0.63 - 2.0
0.63 - 2.0
0.63 - 6.3
0.63 - 6.3
0.63 - 2.0
0.6 - 2.0
0.6 - 2.0
2.0 - 6.3
0.06 - 0.20
0.06 - 0.20
2.0 - 6.3
0.20 - 0.63
<0.2
0.2 - 6.3
2.0 - 6.3
0.06 - 0.20
0.06 - 2.0
0.63 - 2.0
< 6.3
0.63 - 2.0
0.63 - 2.0
0.63 - 2.0
0.06 - 0.20
0.2 - 0.63
2.0 - 6.3
0.06 - 0.20
0.06 - 0.20
2.0 - 6.3
0,63 - 2.0
2.0 - 6.3
2.0 - 6.0
0,2 - 0.6
0,6 - 2.0
*USDA CLASS
I - loam
.c - clay
cl - clay loam
al - sandy loam
sc - sandy clay
sil - silt loam
gel - sandy clay loam
fsl - fine sandy loam
cosl - coarse sandy loam
grfsl - gravelly fine sandy loam
-------
N3
Figure 4-3. Suitability of Areas in the Horsepen Creek
Basin for Septic Tank Use Based on Soil
Characteristics
SOIL SUITABILITY:
POOR TO FAIR-j
POOR -1
2000 4000
SCALE IN FEET
FAIR-
Figure 4-3. Suitability of Areas in the Horsepen Creek
Basin for Septic Tank Use Based on Soil Characteristics
-------
the basin for septic tank use underscores the importance of
intensive site specific soil tests before a permit for any new
septic tanks is issued.
Many of the soil series present in the Horsepen Creek
basin contain soils that have prime farmland characteristics.
That is, some of the mapping subunits of the soils series (i.e.,
soil phases) have been classed as prime farmlands by the USDA
Soil Conservation Service (BY-A-015). Figure 4-4 shows that
most of the Horsepen Creek basin is underlain by soil series that
are wholly or in part prime farmlands.
4.2.2 Water Quality
4.2.2.1 Ground-Water Quality
The natural ground-water quality in the Greensboro
area is quite good. Probably the most troublesome water quality
problem is an objectionably high iron content in some areas. A
more serious ground-water problem in the Greensboro area is that
of aquifer pollution from man-made sources. The most serious
and widespread threat to ground-water quality is from numerous
septic tanks in the area. Where septic tank density is not too
great, the thick soils and saprolite in most areas should serve
to renovate the septic tank effluent quite well before it reaches
any aquifer systems. In many areas, however, low permeability
or insufficient soil thickness limits the number of septic tanks
that can be accommodated satisfactorily. It appears that the safe
number of septic tanks has already been exceeded in some places,
owing primarily to poor siting and/or, maintenance. Most of the
county is considered to have about the same potential for site-
specific problems and ground-water quality degradation from septic
tanks.
53
-------
Ui
-p-
LEGEND
0 gOOO 4000
SCALE IN FEET
SOIL SERIES CONTAINING
PRIME FARMLAND SOILS
Enon
Appling
Cecil
Madison
Mecklenburg
SOIL SERIES CONTAINING
NO PRIME FARMLAND SOILS
Figure 4-4. Occurrence of Prime Farmland Soils in the
Horsepen Creek Basin
-------
4.2.2.2 Surface-Water Quality
4.2.2.2.1 General Description
Information reviewed for assessing existing water
quality conditions of the area streams and lakes in the EIS
study area included data from the City of Greensboro, the North
Carolina Division of Environmental Management Monitoring Survey,
University of North Carolina at Chapel Hill, Guilford College,
and Radian Corporation. Combining and correlating data from
these sources provide a basis for describing present water qual-
ity conditions in the study area and identifying problem sources
which affect surface water quality.
Non-Point Waste Sources
Non-point source pollution occurs as a result of storm
water runoff. Some of the major contributors are urban runoff,
agricultural runoff, runoff from construction activity, and
septic tanks. The type and amount of contaminants in surface
runoff will vary largely as a function of land use. In urban
areas contaminants accumulate in the streets and on land sur-
faces between storm events. During storm runoff, the contami-
nants are carried to the receiving stream and can cause signifi-
cant degradation of stream water quality. In addition, soil ero-
sion currently contributes more than 150 tons of sediment per
square mile to streams in Guilford County (SI-138).
Area Stream Water Quality Classifications
Shown in Figure 4-5 are the monitoring sites operated
by the NCDEM and the City of Greensboro. Water quality data
from these sites were used to assess present conditions of area
streams. The State of North Carolina Division of Environmental
55
-------
ROCKINGHAM CO.
t_n
o
o
>-
in
or
O
"- I
WATER QUALITY MONITORINQ SITE
CPF - NCDEM SITE
GBO - CITY OF GREENSBORO SITE
Figure 4-5. Water Quality Monitoring Sites
Within Study Area
-------
Management has classified area surface water according to the
best intended use of those waters. Stream segments within the
study area are classified as shown in Table 4-3. Class A-II
waters are intended for use as water supply for drinking or food
processing. The intendeduses for Class C waters are for fishing,
boating, wading and other uses except for bathing and water supply.
TABLE 4-3
STATE OF NORTH CAROLINA WATER QUALITY CLASSIFICATION
OF GUILFORD COUNTY STREAMS
Stream Segment Class
Reedy Fork (west) A-II
Moores Creek A-II
Brush Creek A-II
Horsepen Creek A-II
South Buffalo Creek C
North Buffalo Creek C
Buffalo Creek C
Reedy Fork (east) C
Big Alamance Creek A-II
Little Alamance Creek A-II
Alamance Creek A-II
4.2.2.2.2 Horsepen Creek
Basin Description
The Horsepen Creek watershed is located just north
and mostly outside the city limits of Greensboro (see Figure 4-1)
The average width of the basin is about 3 miles, and the length
of the main channel is more than 7 miles. The average channel
slope is 15.5 feet per mile with much steeper slopes than this
57
-------
in the headwaters and tributaries. A summary of average stream
discharge and 7-day, once-in-LO-year low flows (as estimated by
the U.S.G.S.) is presented in Table 4-4 for creeks in the Greens-
boro area.
Except for isolated sections, the floodplain is rela-
tively narrow and contains little development. Much of the flood-
plain in the lower section of the creek is marshland that serves
as a natural deterrent to development. Sections of the flood-
plain in the upper basin have protective restrictions limiting
future growth along the creek. With the exception of Guilford
College, most of the area consists of moderate- to low-density
residential developments. An isolated tract southeast of the
regional airport contains the only well-developed industrial
area.
Horsepen Creek Water Quality
The NCDEM operated two water quality monitoring sites
on Horsepen Creek from February, 1974 to April, 1975. Analysis
of the data shows Horsepen Creek to be of high water quality.
Dissolved oxygen levels are high, and B.O.D. levels are low.
Malfunctioning septic tanks are known to exist in the Horsepen
Creek basin. Data from the NCDEM monitoring site on Horsepen
Creek located at SR 2136 indicate that contamination by fecal
coliforms presently exists. The average count per 100 ml for
seven samples was 2985. However, this value does not contra-
vene stream standards for a Class A-II stream. Data from seven
samples taken at the downstream NCDEM monitoring site at Horse-
pen Creek and U.S. 220 show that the average fecal coliform
count had decayed to 260/100 ml.
58
-------
TABLE 4-4
DRAINAGE AREAS, AVERAGE DISCHARGE, AND 7-DAY -ONCE-IN-10-YEAR FLOW FLOW DETERMINATIONS
FOR SELECTED STREAM
SITES NEAR
GREENSBORO, NORTH CAROLINA
Unit Values
(per square mile)
Drainage Area
(sq. mi.*)
NATURAL WATERSHEDS
1. Upper Reedy Fork (above 19.9
lakes)
2. Reedy Fork (below lakes) 133
2a. Reedy Fork (bolow Buffalo 2r-l4
Creek)
3. Big Alamance (below 116
Little Alaraance)
DEVELOPING WATERSHEDS
1t. Horsepen 15.9
^ 5. Little Alamance 30.5
6. East Fork, Deep River lit. 7
URBAM WATERSHEDS
7. North Buffalo (abo-/e 21.7
S.T.P. )t
8. South Buffalo 29.6
9- Buffalo 100.0
7-Day-Once-In
Average Discharge 10-Year Low Flow
(cfs»«) (cfs)
22.7
101
280
113
17.3
27.0
15.8
2k. 0
28.0
105-0
3.7
13.0
15.0
1.7
1.7
.5
2.1
1.50
95
7.00
Average
Discharge
(cfs/sq. mi.)
1.13
.76
1.10
.97
1.09
.89
1.07
1.11
.95
1.05
7-Day-Once-In
10-Year Low Flow
cfs/sq. mi.
.186
.098
.059
.015
.017
.016
.069
.032
.070
* Square Mile
** Cubic feet per second
Sewage Treatment Plant
SOURCE: NO-111
-------
4.2.2.2.3 Reservoir Water Quality
Lake Higgins, Lake Brandt, Lake Richland, and Lake
Townsend form the reservoir system that provides Greensboro's
raw water supply. Due to the limited water supply, protection
of this reservoir system is widely perceived as a necessity.
Sediment-laden storm runoff is by far the most significant non-
point source pollutant.
Table 4-5 shows stratification characteristics of
Lake Brandt. Tables 4-6 and 4-7 show average chemical and
physical characteristics of raw water withdrawn from Lake Brandt
and Lake Townsend, respectively. The only significant difference
in water quality of these two sources is the higher concentration
of iron (Fe) occurring in Lake Brandt. Physicochemical charac-
teristics of these two lakes (RA-R-406) indicate that temperature
stratification occurs during the summer, which produces partial
to complete oxygen depletion in bottom water and probably signi-
ficantly increases nutrient concentrations during the fall over-
turn event. However, it appears unlikely that these water qual-
ity changes are now accompanied by particularly adverse biological
responses, probably due to the small detention time of these
impoundments. However, eutrophication is a potential hazard to
the quality of the reservoir water.
General Description of Lake Brandt
The drainage area of Lake Brandt is approximately 70
square miles (Figure 4-6). Horsepen Creek drains 16 mi2. Brush
Creek drains 12 mi2 into Lake Higgins, with the excess being re-
leased to Lake Brandt. Reedy Fork Creek drains 32 mi2 with about
10 mi2 draining directly into the lake. U.S.G.S. historical flow
60
-------
STRATIFICATION
Depth (Ft.)
Surface
2
4
6
8
10
12
14
16
18
20
Bottom depth is 36 feet
Source: VA-157
TABLE 4-5
CHARACTERISTICS
17 JULY 1969
Temp. (°F)
88.1
86.9
84.7
84.1
83.7
80.0
77.2
72.3
67.8
66.5
65.8
OF LAKE BRANDT
Dissolved Oxygen (mg/£)
8.0
7.5
7.5
7.5
7.5
7.0
6.0
1.5
0.0
0.0
0.0
records indicate Reedy Fork delivers an average of 1.14 cubic
feet of water per second per square mile (cfs/mi2) to Lake Brandt,
and Horsepen Creek delivers 0.92 cfs/mi2.
The topography of the area is gently rolling with basin
slopes ranging from 5% to 20%. The steeper slopes generally occur
in the Brush and Reedy Fork Creek basins, with the Horsepen Creek
basin having slopes ranging from 5% to 1070.
Lake Brandt is located in the northern Piedmont region
of North Carolina. The primary function of the reservoir is to
provide raw water for the City of Greensboro. Secondary functions
are noncontact recreation such as fishing and duck hunting.
61
-------
CHEMICAL
TABLE
4-6
AND PHYSICAL CHARACTERISTICS
OF RAW WATER SUPPLY
Year
1961-62
1962-63
1963-64
1964-65
1965-66
1966-67
1967-68
1968-69
1969-70
1970-71
1971-72
1972-73
Source:
PH
7.0
7.2
7.2
6.9
6.9
7.1
7.0
7.0
6.6
6.8
6.8
6.9
GR-280
Hard-
ness
27
24
24
19
22
30
32
32
34
30
30
31
(Expressed
Alka-
linity
24
25
26
22
22
31
26
27
26
27
27
27
FROM LAKE BRANDT
as mg/£)
CO 2
6
5
5
5
5
4
4
5
6
7
9
6
Fe
.75
.89
.87
1.33
1.54
.65
.77
1.03
.79
1.52
.88
.72
Mn
.52
.32
.18
.20
.31
.19
.15
.23
.19
.19
.26
.22
Tur
12
20
47
14
16
30
16
23
13
18
Color
146
51
135
140
42
71
83
74
70
97
105
TABLE 4-7
CHEMICAL
AND PHYSICAL CHARACTERISTICS
OF RAW WATER SUPPLY
FROM LAKE TOWNSEND
(Expressed as mg/£)
Year
1969-70
1970-71
1971-72
1972-73
1973-74
1975-76
Source :
pH
6.7
7.0
7.0
7.0
6.6
GR-280
Hard-
ness
38
37
30
32
33
Alka-
linity
31
31
28
29
27
CO 2
6
5
6
6
4.3
Fe
.44
.30
.28
.35
.42
.15
Mn
.17
.25
.15
.18
.22
.03
Tur
11
5
8
9
10.5
Color
39
27
46
38
45
62
-------
o>
U)
ROADS
DRAINAGE BOUNDARY
CREEKS
riHORSEPEN
LJCREEK BASIN
1000 2000
SCALE IN FEET
Figure 4-6. Location Map of the Lake Brandt and Horsepen
Creek Drainage Areas
-------
Impoundment of water commenced in 1923 at which time
the water surface elevation was 736 feet mean sea level (MSL).
In 1959, the lake w;i s raised by seven feet to its present eleva-
tion of 743 feet MSL. The lake has a present volume of 6,750
acre-feet and a surface area of 800 acres. Maximum depth is ap-
proximately 20 feet and average depth is 8.4 feet.
Lake Brandt is monomictic in nature, being completely
mixed and usually free of ice in winter, and thermally stratified
in summer. Lake profiles have shown that in 1977 and other years,
late summer warming pushed the region of the thermocline to the
bottom, thereby eliminating thermal stratification. It is not
well documented that this occurs every year. The dry summer of
1977 caused the lake to drop 4-5 feet, creating a situation con-
ducive to warming throughout.
Existing Water Quality an d T r op h i c S t a t e o_f Lake Brandt
Sampling on Lake Brandt has been performed by several
organizations. These include the University of North Carolina
at Chapel Hill (UNC), North Carolina Division of Environmental
Management (NCDEM), City of Greensboro, Guilford College, and
Radian Corporation. The Radian-Guilford College program (RA-R-507)
has been the most intensive to date. Sampling has been done at sev-
eral sites in both arms of the lake on several occasions over the
1977 season. Radian sampling sites are shown on Figure 4-7,
Examination of data indicates fair to good overall
water quality in Lake Brandt. The water is soft, and conduc-
tivity readings are moderately low (50-150 micromhos/cm), indicat-
ing low levels of dissolved solids. pH measurements generally
show slightly acid to neutral conditions typical of waters drain-
ing forested areas. However, wide seasonal variations in pH have
occurred. In 1977 alone, pH levels both greater than 8.5 and less
64
-------
GREENSBORO
WATERWORKS
LEGEND:
SAMPLING SITE
0 2000 4000
SCALE IN FEET
Figure 4-7.
Water Quality Sampling Stations on Lake Brandt and
its Tributaries
-------
than 5.5 have been recorded. In the past, values in excess of
9.0 have been measured. Many species of fish cannot thrive in a
pH less than 6.0 or greater than 9.0, and few tolerate an environ-
ment with such large variations (NA-199). The low total alkalin-
ities in Lake Brandt provide little buffering capacity to resist
pH changes. This makes the lake susceptible to upstream discharges
and variations in runoff quality which might tend to alter the pH.
Changes in watershed land use away from the natural forested con-
ditions may be affecting runoff water quality and causing pH
fluctuations.
Heavy metals concentrations are generally low and ac-
ceptable with two possible exceptions: lead (Pb) and arsenic (As) .
To ensure protection of fishlife, maximum concentration of Pb
should not exceed 30 yg/£ (NA-199). The maximum set by federal
regulations for public drinking water supplies is 50 yg/£. In
August 1977, Radian recorded levels in Lake Brandt of 40 yg/£ and
60 yg/&, at the dam and in the Horsepen Creek arm, respectively.
Other sampling occasions have not indicated Pb concentrations as
great. Future conditions which may lead to increased Pb loadings
to Lake Brandt should be carefully examined.
The drinking water standard for maximum arsenic con-
centration is 50 yg/£. Whereas no levels in excess of that stan-
dard have been recorded, Radian samples indicated a possible trend
of increasing concentrations in both arms of Lake Brandt from
the headwaters to the dam. Inflow concentrations were on the
order of 1 yg/£, and lake concentrations ranged from 10.8 yg/£
to 16.8 yg/£. It is possible that As-containing sediments are
being recycled under acidic and/or chemically reducing conditions.
Sources of As in the Lake Brandt watershed are unknown at this
time.
66
-------
The trophic state of the lake is best described as mode-
rately eutrophic. During early summer, the lake is thermally
stratified and characterized by hypolimnetic oxygen depletion.
Toward late summer, thermal stratification can disappear as the
region of the thermocline approaches the bottom. Even without
thermal stratification, there is noticeable chemical stratification
Significant oxygen depression with increasing depth is still re-
corded at both deep and shallow stations. This indicates a con-
siderable degree of organic decay processes and concomitant bio-
logical activity within the Lake Brandt ecosystem.
Aquatic macronutrients, i.e., nitrogen (N) and phos-
phorus (P), while not present in extreme concentrations, are pre-
sent in quantities more than adequate for excessive growth of aqua-
tic vegetation. Typical Lake Brandt concentrations have been in
the vicinity of 1.0 mg/£ inorganic -N and .05 mg/& ortho-P (the
major inorganic P-form).
Sampling data indicate that if a macronutrient is in-
deed limiting algal growth in Lake Brandt, it is probably phos-
phorus. A normal ratio of N:P uptake by algae is approximately
10:1 (MA-743) . Except for the samples taken by UNC on 2 April
1975 (N/P = 4.3) (WE-304), N:P ratios have exceeded this value.
Despite Lake Brandt's somewhat nutrient-rich state, neither
stands of aquatic macrophytes nor nuisance algal blooms have
developed. The probable critical factor in this case is the
extremely turbid nature of the water. Measured Secchi disc
depths have been on the order of only one foot. Runoff in the
watershed contains large amounts of clay which produce a non-
settling suspension. Hence, it is likely that persistent, high
suspended solids concentrations limit algal growth through re-
duced light penetration.
67
-------
Lake Brandt is particularly susceptible to nutrient
inputs because it is so shallow. Most lakes and reservoirs
act as nutrient "traps" or sinks. Much of the incoming nutrient
loading ends up settling with the sediment. The deeper the lake
and the longer its detention time, the more effective the sink.
Radian's calculations indicate that Lake Brandt's mean depth is
8.4 ft and its average hydraulic detention time is 46 days. This
makes the- lake sensitive to changes in quality of stream inflow.
Much of the nutrient input remains in the epilimnion and is
therefore available for plant uptake. Furthermore, the lack of
thermal stratification in late summer makes scouring of nutrient-
rich benthic deposits possible. Therefore, Lake Brandt is very
likely to remain in a eutrophic state. If there is a significant
change in the water quality in Horsepen Creek and/or Reedy Fork,
this change is likely to be felt fairly rapidly in Lake Brandt.
4.2.3 Biological Components
4.2.3.1 Terrestrial Environment
4.2.3.1.1 Vegetation Types
Potential Natural Vegetation
As influenced by topography, climate, and soils, a cli-
max hardwood forest developed in Guilford County which was domin-
ated on upland sites by white, red, and black oaks, and with post,
blackjack, southern red and scarlet oaks achieving prominence on
the drier sites. Floodplains and low-lying moist sites were dom-
inated by willow oak, swamp red-oak, and shagbark hickory; beech
was found in sheltered ravines (00-004).
Today, almost no virgin forest remains of the original
climax cover of the North Carolina Piedmont. Clearing of the
68
-------
native forests for lumber began about 1750 (FU-072) and the cut-
over areas were subsequently cleared for agriculture. Fields
were cultivated until erosion and cropping reduced their fertil-
ity past the point of economic return and were then abandoned.
Present Vegetation
The mixed pine-hardwood stands are the most common type
of forest cover in the study area; there are late-successional
stands resulting from regrowth following logging or cultivation.
Species composition varies considerably, and a continuum of stands
occurs between the driest, best-drained sites and the moister,
richer sites in sheltered ravines and lower slopes. Though bas-
ically dominated throughout by white, red, and black oaks, the
drier end of the continuum is distinguished by scarlet, post, and
blackjack oaks, with chestnut oak on the most rugged sites. The
opposite end of the continuum is characterized by the presence of
American beech, sweetgum, green ash, shagbark hickory, and walnut.
Pines may be found on all sites , usually as scattered clusters or
individuals of shortleaf pine. The upland forests correspond
roughly to ASF Types 52, 78, and 87, but their successional na-
ture makes them indistinct, and the degree of overlap is so
great as to justify no ecological distinction between them.
Floodplain forests are very restricted in distribution
owing both to the fact that the study area lies at the headwaters
of a drainage basin and to the encroachment of agriculture and in-
dustry. Several successional phases of this forest type are evi-
dent, but the most common appears to be dominated by American elm
and/or green ash, and corresponds roughly to ASF Type 93. Ripar-
ian woodlands are a subtype of this floodplain forest type, form-
ing a narrow strip on either side of stream courses. Sycamore is
clearly the most characteristic tree of streambank situatibns,
together with American elm and green ash. Black willow is found
69
-------
on disturbed sites. Japanese honeysuckle frequently forms an
almost continuous carpet over the forest floor, and other vines,
including poison ivy, Virginia creeper, and grape are common.
The pine woodlands in the study area are almost always
nearly pure stands of Virginia pine grown very close together and
forming a dense canopy. Occasional plantations of shortleaf pine
are found. Virginia redcedar is frequently encountered as an un-
derstory species in successional stands of pine. Elsewhere, red-
cedar is a typical early-succession dominant on abandoned fields;
in the study area, one heavily grazed field was observed in which
redcedar had established itself in the absence of pine.
Old field revegetation varies according to time elapsed
since abandonment, with broomsedge becoming dominant, together
with various tall, weedy forbs. Pine seedlings may invade as early
as the third year. Farm and pasture make up a sizeable percentage
of the study area, occupying 18 percent of the total non-urban land.
Corn, tobacco, cotton, and feed grains are the most frequently
grown crops.
Sensitive Botanical Areas
Reports (HA-544; CO-582) indicate that sensitive plant
species may be found in the study area. Ginseng is a plant nearly
extirpated in pioneer days when it was dug and sold for its sup-
posedly medicinal qualities. It is found in rich woods and, con-
sequently, would be expected to be restricted in Guilford County
to floodplain forests and the moist end of the upland hardwoods
continuum. The southern rain-orchid (Habenaria flava) and Nes-
tronia (Nestronia umbellula) are listed as "threatened throughout"
their range in North Carolina. The orchid is a moist lowland
species and Nestronia occurs in the more moist mixed hardwood
stands. None of these species were found during site visits.
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4.2.3.1.2 Fauna
Relationship to Habitat
Generally speaking, the more open upland and floodplain
forests provide the best habitat for most wildlife species. Both
cover and food are abundant, and the large proportion of edge be-
tween woodlots and fields adds to their value. Mammals typical
of these forests include the chipmunk, gray squirrel, and fox
squirrel. Opossum, white-footed mouse, meadow jumping mouse, and
striped skunk are common ubiquitous species often found in open
woodlands. Deep-woods species which may have been more widely
distributed in the past include least shrew and southern flying
squirrel. Virginia white-tailed deer are infrequently found in
the area, often feeding in fields and clearings adjacent to
woodlots. Red fox and gray fox are also resident in woodlands but
are likewise uncommon. A large number of small birds are charac-
teristically associated with woodlands; these include the woodpeck-
ers, eastern phoebe, eastern wood pewee, blue jay, Carolina chick-
adee, brown thrasher, cardinal, rufoud-sided towhee, and a variety
of nesting and migrating warblers. The pileated woodpecker, rare
now in the area, is a typical deep-woods species declining under
the pressure of habitat loss. Forest raptors include Cooper's,
broad-winged, and red-shouldered hawks, as well as the great
horned and barn owls. Several reptiles, including the eastern
fence lizard and eastern garter snake, are found in woodlands as well
as other habitats; the five-lined skink and southeastern copper-
head tend to prefer wooded areas.
Riparian and bottomland habitats are characterized by
a group of species which tend to be most abundant in such situa-
tions. These include muskrat, belted kingfisher, tufted titmouse,
nuthatches, Carolina wren, Blue-gray gnatcatcher, kinglets, and
several of the vireos and warblers. Most amphibians are restricted
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to moist areas near water, and several of the snakes, including
the eastern ribbon snake and rough green snake, are also found
mainly near streams. Raccoons are almost always found near water.
The dense pine thickets afford habitat to many of the
small bird and mammal species including a few, such as red cross-
bill, pine siskin, pine warbler, and pine vole, that are more
characteristic of conifers than other vegetation types. However,
the uniformity of physical structure of pine stands and their
dense shade which reduces the growth of understory vegetation
tends to make them generally less valuable habitats than the
older hardwood stands.
Old fields, including young pine stands before the
canopy closes, tend to have a distinct faunal assemblage which
includes many of the widespread species of broad tolerance men-
tioned above. The white-footed mouse is especially common in
old fields. In addition, the eastern cottontail, hispid cotton
rat, and house mouse prefer the dense growth of tall weeds and
grasses (MC-255). Birds commonly associated with old fields and
clearings include sparrow hawk, marsh hawk, bobwhite, killdeer,
common nighthawk, mockingbird, robin, eastern meadowlark, Ameri-
can goldfinch and most species of sparrows.
Status of Game Animal Populations
During brief field investigations conducted in November,
1976 by Radian Corporation biologists, deer tracks were seen near
Lake Brandt. Hendrickson (HE-214) reported deer signs in the
South Buffalo Creek drainage. Deer probably utilize the relatively
continuous woods and thickets in the study area as routes of move-
ment to and from the larger areas of woodlands. Although habitat
for deer is greatly fragmented in Guilford County, the combina-
tion of woody and old-field herbaceous cover could probably sup-
port a much larger population than is now found there.
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Gra> and fox squirrels are generally hunted in wooded
riparian habitats; good hunting is localized in these areas in
Guilford County. Nests were commonly observed in the study area
in November, 1976 by Radian biologists. Availability of food--
primarily acorns--seems to be the major factor determining the
year-to-year variations in size of the squirrel population, al-
though its overall limits are set by the availability of woodland
habitat (NO-115) .
Waterfowl of various kinds utilize the lakes, streams,
and ponds in Guilford County, primarily in winter and during mi-
gration. Canada geese are common winter migrants, and mallards
are common winter residents. Other species observed regularly,
but not commonly, include pintail, gadwall, blue-winged and green-
winged teal. Only the wood duck is listed as a permanent resi-
dent (DA-227). Hunting for waterfowl is limited in Guilford
County. Lake Brandt and possibly other lakes were hunted as re-
cently as 1967 (VA-157).
Red fox, gray fox, and raccoon are popular quarries,
hunted with dogs and/or from horseback. Extreme pressure re-
sulted in population declines during the 1950's. Raccoon sign
was found along Horsepen Creek by Radian biologists, corroborat-
ing Hendrickson1s earlier observations (HE-214).
In addition to the above species, muskrat and opossum
are trapped for fur. Muskrat is the most important furbearer in
Guilford County. Muskrat sign or road kills were noted on or near
Horsepen Creek by Hendrickson (HE-214). Muskrat abundance is
probably controlled mainly by habitat availability. Adequate
combinations of food, cover, and permanent, relatively deep water
are found naturally only along the main streamcourses and their
tributaries. ^f\>-m ponds were not examined in Lhe field but it
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is probable that they supply additional habitat. Muskrat are
probably also found along the shoreline of Lake Brandt where
cattails and other emergent vegetation offer a combination of
food and cover.
Endangered Species
None of the mammals of Guilford County are considered
to be endangered either by the State of North Carolina or by the
U.S. Fish and Wildlife Service (US-305, NO-120). The peregrine
falcon which may rarely be seen in migration is officially classed
as endangered by both entities, as is the bald eagle. The latter
species is listed by Dawley (DA-227) as a rare permanent resident
in the county. This list was published, however, in 1954, and no
recent confirmations are available. Bald eagles prefer wooded
areas near water and do not tolerate human activity within a mile
or two of an active nest. If any eagles still remain in Guil-
ford County's fragmented landscape it is unlikely that they
breed there. The red-cockaded woodpecker is also listed by Dawley
as a permanent resident, although recent confirmation is not avail-
able. The sharp-shinned hawk, a species listed as threatened
(CO-582), is reported to nest near Lake Brandt. The State of
North Carolina considers the eastern diamondback rattlesnake an
endangered species, although it is not on the national list. Al-
though range maps indicate that this species' overall distribu-
tion includes Guilford County (CO-391), its presence there has
not been confirmed. The North Carolina Wildlife Resources Commis-
sion considers the Dyar moth (Acrabasis fettella) rare in the
state which is at the edge of its range. This moth is closely
associated with shagbark hickory and may reside in the county.
The white-crowned sparrow, though not in danger as a
species, is at the edge of its range in North Carolina. The
state's only known wintering population is located in the Horse-
pen Creek drainage. A small number of wintering birds have been
74
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observed around farm buildings adjacent, to the Greensboro-Winston
Salem regional airport. They probably utilize the waste grain
to some extent. Owing to its unfavorable location, it is unlikely
that residential land development would interfere with this popu-
lation in the near future although industrial use of the land is
not precluded.
Figure 4-8 shows the locations of all areas considered
especially important for the area's wildlife. It should be em-
phasized that the most critical aspect of the area's fragmented
woodland habitat is not the areal extent of woodlots, but the
degree to which they are interconnected by strips of standing
timber, thickets, and fencerows. Although not mapped because
of their complexity, these linkages make it possible to main-
tain the present diversity of animal life by permitting the
animals to move between many individual woodlots which could not
subsist in the habitat afforded by a single forest stand.
4.2.3.2 Aquatic Environment
4.2.3.2.1 Horsepen Creek
Horsepen Creek flows through a largely agricultural
watershed in which residential development is occurring at an
accelerated pace. Throughout the headwaters of the creek,
the banks are unwooded or bordered only by a narrow fringe of
trees; the lower portion, near the mouth of the stream at Lake
Brandt, flows through a forested floodplain.
Flow in the creek is not regulated, and typical flows
are low. Although the stream is perennial, low flows are little
more than a trickle. Water quality data are not extensive for
Horsepen Creek, but observations of the aquatic ecosystem in the
stream suggest that pollution is not strongly limiting. The
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ROCKINGHAM CO
I HABITAT OF WHITE-CROWNED SPARROW, i1
I \ i
POPULATIONS OF FRESHWATER CLAMS
RELIEF POPULATION OF CRESENT SHINER
SHS QUILFORD COUNTY GAME FARM LAND
Figure 4-8. Biologically Sensitive Areas
-------
upper portions of the creek, as far as Radian Station H5 (Figure
4-9) are narrow (generally less than sixteen feet in width)
and alternate between relatively shallow riffles up to a foot
in depth and pools several feet deep. The stream channel is
cut to bedrock in the upper portions. Cracking and slumping of
the channel sides are evident only where all woody vegetation
has been cleared from the banks. The bottom in the upper por-
tion is chiefly small rock and gravel with sands of various
sizes. Below Radian Station H5, the stream widens and deepens.
Silt-size particles become more prominent, which increases
turbidity.
At the poinr where Horsepen Creek pnters Lake Brandt,
a small marsh swamp of roughly an acre in size has developed.
A brief visit to this marsh was made by Radian biologists, but
no detailed observations were made; no other information is
available. The bulk of the area is relatively open with manna-
grass, bullrush, and cattail the most prominent plants. Alder,
black willow, and buttonbush, with a few individuals of red maple,
form a dense band around the outside of the swampy area, decreas-
ing in density toward the center. Bladderwort and water hyacinth
are common in areas of standing water. Mosquito fish were also
observed.
The aquatic organisms observed by Radian biologists
point to generally healthy conditions in the stream. Caddisfly
larvae, generally intolerant of organic pollution, were abundant
at nearly all stations. Moderately intolerant dragonfly larvae
were found at one station accompanied by filamentous green and
blue-green algae that were growing on adjacent rocks. Although
algae were not abundant on the creek bottoms, they were more
commonly observed on Horsepen than on the Buffalo Creeks or
Reedy Fork; it is likely that the relative clarity of the water
and stability of the bottom of Horsepen Creek account for the
larger number of algae.
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ROCKINGHAM CO.
00
o
o.
I
I-
w
cr
O
O RADIAN OBSERVATION STATIONS. 1876 ^
* N. CAROLINA WILDLIFE RESOURCES
COMMISSION. 1963 (CA-380)
D FEDERAL WATER POLLUTION CONTROL
ADMINISTRATION. 1908 (FE-187)
Figure 4-9. Sampling Localities: Aquatic Biota
-------
Both Hendrickson (HE-214) and Radian biologists noted evidence
of a small population of freshwater clams at and about station
H5. These have not been identified as to species.
Hendrickson visited Horsepen Creek in 1975 and reported
on the vertebrate fauna he found there (HE-214). Fishes he ob-
served included:
Crescent shiner
River chubsucker
Tesselated darter
Speckled ki1lifish
Piedmont chub
The first of these is noteworthy in that it is known
primarily from the Roanoke drainage and occurs in only one other
locality in the Cape Fear drainage. The species is not, however,
considered endangered. Amphibians observed by Hendrickson inclu-
ded the dusky salamander, green frog, and bullfrog. He also ob-
served a northern water snake during his investigation.
4.2.3.2.2 Lake Brandt
At the present time, comparatively little information is
available on the aquatic ecosystem of Lake Brandt. The informa-
tion presented here was furnished by Scott Van Horn of the North
Carolina Wildlife Resources Commission (VA-157).
Lake Brandt was built in 1921 and expanded to its pre-
sent size of 2000 surface acres in 1960. The lake has a mean
depth of 36 feet and stratifies in summer with the thermocline
at about 13 feet. Temperatures measured in July, 1969 were 88°F
at the surface and 65°-76°F below the thermocline. Dissolved
oxygen was adequate in the surface layer (8 mg/£) but greatly
depleted below the thermocline (0-1.5 mg/£).
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The shallower portions of the lake, especially the mouth
of Horsepen Creek and Reedy Fork as it enters the lake, become
choked in summer with extensive beds of water lilies and pondweeds
of various kinds. No information is available regarding algae
found in the lake or the extent to which spring and/or fall turn-
over influences their abundance. Table 4-8 lists fish found in
the lake. Fishing on the lake is popular, although permitted only
from city-owned boats. Lack of forage species has been a problem
in Lake Brandt, and threadfin shad were introduced in 1967 and
1969. Fish from these stocks winterkilled, but restocking in 1972
seemed to produce a surviving population. Because of low avail-
ability of forage fish, largemouth bass are small and slow-growing,
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TABLE 4-8
FISHES OF LAKE BRANDT
Game Fish
^umpkinseed
^luegill
Black crapple
1White crappie
Yellow perch
Redbreast sunfish
Warmouth
Green sunfish
3Chain pickerel
2Largemouth bass
3Whlte bass
Non-Game Fish
1>2Yellow bullhead
Brown bullhead
Black bullhead
Flat bullhead
!'2White catfish
Channel catfish
Lepomis gibbosus
Lepomis macrochirus
Pomixis nigro-maculatus
Pomixis annularis
Perca flavescens
Lepomis auritus
Chaenobryhus gulosus
Chaenobryhus cyanellus
Esox niger
Micropterus salmoides
Morone chrysops
Ictalurus natalis
Ictalurus nebulosus
Ictalurus melas
Carp
Goldfish
Golden shiner
3Threadfin shad
3Blueback herring
Major species by weight (Source: VA-157)
>
"Major species by number (Source: VA-157)
Stocked but possibly not surviving over winter
Ictalurus platycephalus
Ictalurus catus
Ictalurus punctatus
Cyprinus carpio
Carassius auratus
Notemigonus chrysoleucas
Dorosoma petenense
Alosa aestivalis
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CHAPTER 5
EFFECTS OF THE PROPOSED ACTION
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5.0 EFFECTS OF THE PROPOSED ACTION
5.1 The Natural Environment
5.1.1 Air Quality
The standard "criteria" pollutants describing air
quality impacts are total suspended particulates (TSP), sulfur
dioxide, nitrogen dioxide, carbon monoxide, and hydrocarbons
(photochemical oxidants). Odor is not a part of the federal
air quality standards but is of concern to this project. The
impact of this airborne pollutant is addressed in the next sec-
tion.
Direct Impacts
Of the five criteria air pollutants, only TSP is of
any significance to this project. Small amounts of the other
pollutants will be emitted during construction, but their impact
on existing air quality will be negligible. Fugitive dust
emissions resulting from construction of the Horsepen Creek
interceptor system will cause a short-term local increase in TSP
levels.
Studies have shown that quantity of dust generated can
be correlated with climate, soil type, and extent of construction
activity (EN-071). In general, maximum emission rates expected
are one ton of TSP per acre of construction activity per month.
This represents a worst-case condition; actual TSP levels may be
significantly less, depending on the factors listed above. The
total acreage under construction at any one time will probably
be small (1-5 acres). Consequently, adverse impacts related to
TSP levels are expected to be minor.
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Indirect Impacts
Secondary air quality impacts will occur due to
growth-related aspects of the proposed action. The projected
population increase in the study area after project completion
will most likely cause increases in the criteria air pollutants.
The proposed action favors a low density type of development
with relatively low TSP levels when compared to high density
development TSP levels. In any case, urban particulate emissions
will replace rural/agricultural particulate emissions due to expect-
ed land use charges. Unfortunately, urban particulate emissions are
probably more hazardous to health. Geographical population distri-
bution is not expected to have a pronounced effect on area levels
of the other criteria pollutants, so all alternatives proposed'
would have the same impact assuming population growth is constant.
The status designations required by the 1977 Clean Air
Act Amendments listed Guilford County as better than the national
standards for all criteria pollutants. For areas better than
the national standards, increases in criteria pollutants due to
growth are controlled by prevention of significant deterioration
regulations. It is not anticipated that the proposed action
will have any significant deleterious secondary air quality im-
pacts .
5.1.2 Odor
In general, no adverse odor impacts are associated with
construction and operation of the interceptor, force main, and
pump station network as proposed. The present sanitary sewerage
system in the Horsepen Creek area is oversized in the upper
portion of the basin resulting in occasional septic odors at
manholes and wet wells due to the slow moving wastewater stream.
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This condition usually occurs during dry periods when low flow
conditions are most pronounced. Additional odor problems as-
sociated with occasional surcharging of lift stations have been
reported.
Odor problems associated with a slow-moving wastewater
stream in the upper basin will not be completely eliminated by
the proposed action. However, overall impacts of the proposed
action should result in a net decrease in odor problems in the
area due to elimination of the present system of lift stations
which occasionally surcharge. Flushing of lines in the upper
basin area as a method of reducing septic odors is probably not
a sound approach. Water supplies in the area are limited, and
low flow conditions inevitably coincide with peak water demand
periods.
5.1.3 Noise
Direct Impacts
The principal noise impacts expected with the proposed
action will occur during the construction phase. Heavy equipment
operation for trenching, pipe laying, backfilling, etc., will
create locally excessive noise levels. During construction of an
interceptor, mild adverse reaction may be expected at a distance
of up to about 700 feet due to trucks, cement mixers, etc., in
the area. Adverse reactions may be expected at distances up to
2000 feet if rock-blasting or drilling is required. If an average
pipe-laying rate of 3000 feet/month is assumed, noise impacts
may be felt in a residential area for a period of two weeks to
a month. Most of the interceptor routes for the proposed action
are not contiguous with residential areas, so objections should
be minimal.
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Terrestrial wildlife in the area may exhibit an
avoidance response due to noise during construction. Species
which are particularly dependent on acoustical signals will be
affected the most. Animals which leave the immediate vicinity
of the construction can be expected to redistribute in normal
fashion after the disturbance in the area is over.
Indirect Impacts
After the construction phase of the proposed action
is completed, noise levels in the area may decrease slightly
due to elimination of seven lift stations. This decrease will
probably cause an imperceptible reduction in ambient noise levels
Long-term impacts of the Horsepen Creek interceptor system with
respect to noise will result in an increase in ambient noise
levels. This increase is due to urbanization of the area with
attendant increases in traffic, construction, industrialization,
and other noise-producing sources. The proposed action will
minimize future noise impacts by favoring a lower density,
septic tank type of residential development, as opposed to a
high density, sewered type of residential development.
5.1.4 Soils
Most of the Horsepen Creek basin area is in the Cecil,
Mecklenburg, Madison, and Enon soil series, all of which have
phases that are classified as prime farmland soils. Underlying
these soil associations is a relatively thick, impermeable layer
of saprolitic material. In general, the soils in the area are
poorly suited to septic tank usage. The upland soils on the
basin margin and the soils throughout the lower basin are better
suited than other soils in the area for septic tank use. Most
of the farm and pasture land presently exists in the southwestern
portion of the basin.
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Direct Impacts
Construction of the proposed Horsepen Creek intercep-
tor system will result in devegetation or disturbance of
approximately 123 acres assuming a 75-foot right-of-way.
Erosion of these areas may be a particular problem in the central
(non-upland) part of the basin where the Enon-Mecklenburg soil
association is common. This soil association is considered to
have a pronounced erosion potential. Sediment control measures
may be necessary during the construction phase when this soil
type is encountered, particularly in areas of high slope or
proximal to the creek and its tributaries.
Present conditions indicate that large amounts of
colloidal sediment particles are being delivered to Horsepen Creek
and Lake Brandt. Construction of an interceptor along the creek
will likely result in an increase in the delivery of settleable
solids. This could have a negative impact on the aquatic biota
in Horsepen Creek. Sessile organisms may be particularly
affected. Impacts associated with stream siltation and sub-
strate modification due to increased sediment delivery during
construction should be short-term with a return to baseline
conditions following the construction phase.
Indirect Impacts
Urbanization of all the remaining developable land in
the Horsepen Creek area is projected as a result of the proposed
action. This includes the land presently in use for farm and
pasture (approximately 18% of the total study area) as well as
forested areas (approximately 38%). However, most of this land
would be lost from potential productivity in any case. Its
current economic value for suburban development is much greater
than its agricultural value. This change in land use would
^ "7
o/
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occur under all the alternatives considered, including the "No
Action" alternative.
Results of the STORM modeling efforts on Horsepen Creek
(RA-R-667) water quality indicate that total suspended sediment
loads will decrease due to land use changes during development.
A 46% decrease is predicted for septic tank development. Like-
wise, a 467o increase in settleable soils is predicted. The pri-
mary impacts of these sediment loading changes will be discussed
in detail in the hydrology section.
5.1.5 Hydrology
The Horsepen Creek interceptor system is expected to
have a significant impact on the quality of water in Horsepen
Creek and Lake Brandt. Direct impacts associated with construc-
tion should be minor if proper sediment control measures are
used. However, indirect impacts associated with ultimate devel-
opment in the watershed are more complicated to assess. Lake
Brandt is currently a major water supply for the city of Greens-
boro. As such, protection of its water quality is the most
important environmental concern of this project. Analysis of
expected impacts of the proposed action relies primarily on water
quality predictions generated by the STORM modeling efforts.
These results will be discussed in the section on surface water.
5.1.5.1 Ground Water
Direct Impacts
Construction of the Horsepen Creek interceptor should
not have an appreciable effect on ground-water supply or quality.
Elimination of the existing system of force mains and lift sta-
tions should decrease surcharging and exfiltration in the area.
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Current ground-water supplies are of adequate quality for indi-
vidual users. The thick soils and saprolite are of low perme-
ability which tends to protect ground-water quality.
Indirect Impacts
The ultimate development of the Horsepen Creek basin
will be the most serious impact on ground-water quality. The
proposed action implies a pattern of development that includes
increased septic tank and sanitary sewer use in the basin. Pres-
ent estimates predict a full development population of about
18,700 (a 1307o increase). The Horsepen Creek interceptor system
has the capacity to serve approximately 12,000. Assuming that
good, up-to-date engineering practices are used to prevent
exfiltration, an increase in sewered population should not harm
ground water quality. Elimination of some existing septic tanks
by connection to the new lines may initially reduce present
levels of ground water pollution. The impact of septic tank
proliferation in the area on ground-water quality will be a
function of the degree of stringence and enforcement of local
ordinances concerning their use.
The urbanization associated with the proposed project
will increase ground-water withdrawals by residences which are
not included in Greensboro water supply system. The amount of
withdrawal is not expected to deplete the aquifer, but the in-
crease in impervious area may reduce recharge rates slightly.
Primary recharge areas for the aquifer system are the inter-
fluves or upland areas. Approximately 10-15 percent of annual
precipitation infiltrates into subsurface to become ground-
water recharge.
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The greatest threat to ground-water quality may be the
potential for high density septic tank development, particularly
in upland recharge areas. Fecal coliform levels are already
high in Horsepen Creek, and septic tank contamination of the
ground water could elevate these levels to the point of becoming
a health hazard. Mitigating measures to prevent this occurrence
will likely be through land use controls and ordinances men-
tioned earlier, especially the newly enacted Guilford County sep-
tic tank ordinance. Specific recommendations for minimizing im-
pacts on ground water and Lake Brandt water quality will be dis-
cussed in the next chapter.
5.1.5.2 Surface Water
5.1.5.2.1 Effects on Horsepen Creek Water Quality
Direct Impacts
Direct impacts on surface water during construction of
the interceptor system are primarily related to increases in
sediment loading to Horsepen Creek and ultimately Lake Brandt.
The expected increase in settleable solids discussed in the soils
section should be of no identified consequence to surface water
quality. Colloidal particles in sediment runoff from erosion
are often nutrient enriched, and a short-term increase in nu-
trient levels in the creek may result.
Indirect Impacts
The urbanization which is expected after completion of
the proposed project will have serious consequences on surface
water characteristics in Horsepen Creek and Lake Brandt. Predic-
tions for changes in pollutant loads for sewered and septic tank
development scenarios using the STORM water quality model will
be discussed in the following section.* However, before examining
*A detailed water quality monitoring and modeling study has been
completed for this EIS (RA-R-667).
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the model results a brief discussion of the sources of non-point
pollution is appropriate.
When examining non-point pollution it is necessary to
differentiate between dry weather periods and wet weather periods.
Sources of non-point dry weather pollution include ground water
discharge, septic field drainage, and sanitary sewer leakage.
These can be classified as lateral inflow sources. In contrast,
wet weather non-point pollution is primarily due to stormwater
runoff, or overland flow. Generally speaking, stormwater runoff
has a more deleterious effect on surface water quality than
lateral inflow pollutant sources.
The following is a list of sources of pollution present
in urban runoff:
1. Street "materials" including animal wastes,
garbage, grit, oil, road salt, cinders, and
residual particulates resulting from auto,
tire, and brake use.
2. Surface non-street "materials" including
animal wastes, garbage, fertilizers, chemicals,
pesticides, household, and commercial refuse
awaiting collection.
3. Silt from urban construction activities.
4. Leakage and overflow from defective and over-
charged sanitary and combined sewers.
5. Deposition of airborne particulates.
6. Materials discharged in commercial and indus-
trial plant floor drains.
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7. Unrecorded and undetected discharges from
diverse point sources of liquid wastes and
leachates, including improper connections
to storm drains.
STORM Model Results
The "STORM" model uses information on precipitation
rates, pollutant accumulation rates, and hydrologic characteris-
tics of the watershed under investigation in order to simulate
stream-flow and water quality. The model was calibrated to
Horsepen Creek conditions using available historical data from
the U.S. Geological Survey (U.S.G.S.) and data collected during
a monitoring program conducted by Radian Corporation. The
methodologies used in calibrating and using the STORM model as
a predictive tool are discussed in detail in the section entitled
"Investigation of Water Quality Impacts Related to Development of
the Horsepen Creek Basin" found in RA-R-667.
Two basic scenarios were evaluated using the STORM
model: 1) development with sanitary sewers only, and 2) develop-
ment with septic tanks only. The existing annual pollutant loads
to Lake Brandt from Horsepen Creek are presented in Table 5-1.
The STORM predictions of future annual loads from Horsepen Creek
for development with a sanitary sewer system and with septic tanks
are presented in Table 5-2 and Table 5-3, respectively. The year
2000 population projections of 18,700 were used for both scenarios.
The ultimate increase in population associated with the future
sewer service alternatives will significantly increase the poten-
tial adverse impacts of these alternatives beyond the discussion
presented here for the 20 year design period.
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TABLE 5-1
AGGREGATED EXISTING ANNUAL LOADS TO LAKE
BRANDT FROM HORSEPEN CREEK
Parameter
Sediment
Total Nitrogen
Orthophosphate
Annual Load (tons/year)
13041
63.5
0.47
TABLE 5-2
FUTURE ANNUAL LOADS FROM THE HORSEPEN CREEK BASIN
DEVELOPED WITH A SANITARY SEWER SYSTEM
Parameter
Suspended Solids
Settleable Solids
B.O.D.
Total Nitrogen
Orthophosphate
Fecal Coliform
Annual Load (tons/year)
11553
19.8
88.3
48.3
0.702
1,396,330 x 109 MPN
Percent
Change from
Existing
-13.0
+78
+ 1.0
-31
+49
+65
TABLE 5-2!
FUTURE ANNUAL LOADS FROM THE HORSEPEN CREEK BASIN
DEVELOPED WITH SEPTIC TANKS
Parameter
Suspended Solids
Settleable Solids
B.O.D.
Total Nitrogen
Orthophosphate
Fecal Coliform
Annual Load (tons/year)
7045
24.6
106
43.1
0.8
1,695,325 x 109 MPN
Percent
Change from
Existing
-46
+46
+20
-32
+70
+100
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The model predictions indicate that water quality of
Horsepen Creek will be a partial function of the type of urban-
ization that takes place. It is important to stress that the
two scenarios represent extremes; the proposed action will en-
courage a type of development intermediate between these extremes.
Nevertheless, the model results should provide a reasonable,
qualitative prediction of water quality changes expected.
Comparison of the results for each scenario with exist-
ing conditions indicates that suspended solids and nitrogen
loadings will decrease. In particular, a septic tank type of
development would result in a significant reduction (46% of
existing) in suspended solids levels. Conversion of almost all
agricultural land and much of the forested area in the basin to
residential use, and resultant decreases in erosion rates accounts
for this change.
Phosphorous, biological oxygen demand (BOD), and fecal
coliform levels are expected to increase with greater increases
of these pollutants expected for septic tank development.
Horsepen Creek currently has high water quality with corres-
ponding low BOD levels and high DO levels. Increasing the BOD
and phosphorous loading to Horsepen Creek will lower dissolved
oxygen levels and encourage eutrophication, both considered
negative impacts. Some aquatic organisms may suffer a reduc-
tion in available habitat area as a result of these changes.
5,1.5.2.2 Effects on Horsepen Creek Flow
Urbanization of the Horsepen Creek watershed will cause
changes in streamflow characteristics. Increases in impervious
areas result in lower base flows, shortened lag times during
storms, and higher flood rates. All of these effects are due to
decreased infiltration during storm events.
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The STORM model (RA-R-667) results predict an increase
in road mileage in the basin from the present 55 miles to 128
miles with sanitary sewer development or 155 miles with septic
tank development. Base flow to Horsepen Creek is estimated to
decrease by 17 percent after urbanization with sanitary sewerage.
Base flow rates are presently low, and further reduction may
impair the aquatic habitat.
Shortened lag times and higher peak flood rates occur
as a result of urbanization. Increased flood rates may cause
greater channel erosion and alteration of streambed characteris-
tics. The STORM model does not consider stream channel erosion,
so predicted decreases in sediment loading may be high. The
actual amount of erosion will depend on streambed composition
and the severity of storm events. A by-product of shorter lag
times and increased flows is enlargement of floodplain areas.
Expansion of the Horsepen Creek floodplain may necessitate re-
strictions on residential development in these areas.
5.1.5.2.3 Effects on Lake Brandt Water Quality
Water quality results indicate that Lake Brandt has
fair to good water quality at present. Turbidity levels due to
suspended solids loading are high, but have been decreasing
gradually (GR-280). Secchi disk depth, a measure of light
penetration in the water column, is approximately one foot.
Biological productivity is limited by light penetration; con-
sequently the lake is classified as only moderately eutrophic.
Urbanization of the basin will increase the concen-
trations of heavy metals in storm water runoff. Analyses to
date indicate lead (Pb) levels from 5 yg/£ to 60 yg/£ are present
in Lake Brandt. Data from the water quality monitoring programs
indicate that a 20 percent increase in annual lead (Pb) yield from
Horsepen Creek will result from development with sanitary sewers
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(RA-R-667). The proposed action can be expected to increase lead
levels similarly due to the increased development acreage neces-
sary for septic tank residences. Primary drinking water standards
give a maximum "safe" level of 50 yg/£ (lead). For this reason,
any increase in lead levels over present levels could result in
unsafe lead levels in parts of Lake Brandt. Annual lead loads
may not be as significant as lead concentration "peaks" after
storm events when road surfaces are flushed.
The drinking water standard for maximum arsenic con-
centration is 50 yg/fc. Water quality monitoring results indi-
cate a possible trend of increasing concentrations in both arms
of Lake Brandt from the headwaters to the dam. Even though in-
flow concentrations were on the order of 1 yg/£, lake concen-
trations ranged from 10.8 yg/£ in the Reedy Fork arm to 16.8
yg/A at the dam. It is possible that arsenic-containing sediments
are being recycled under acidic and/or chemically reducing con-
ditions. Sources of arsenic in the Lake Brandt watershed are un-
known at this time. As forested areas in the Horsepen Creek basin
are developed, waters draining these areas can be expected to
change in pH. Wide pH fluctuations have been observed in Lake
Brandt in recent years. Since Lake Brandt water has a low buf-
fering capacity, it is particularly susceptible to pH changes from
inflowing water. A permanent or seasonal change in pH of Horsepen
Creek water could alter the equilibrium between trace elements in
solution and in bottom sediments. This in turn could increase
arsenic concentrations to unsafe levels in Lake Brandt.
Water treatment at the City of Greensboro filter plants
consists of alum and lime addition, followed by filtration,
sedimentation, and chlorination. Present detection limits at
these plants for heavy metals are approximatley 10 yg/&, but no
no heavy metals concentrations above 10 Vg/& have been noted to
date.
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Nutrient levels in Lake Brandt are presently 5 to 10
times greater than levels considered limiting to biological
growth. Typical values considered limiting for algal growth
are 0.025-0.1 yg/£ total inorganic-N, and 0.001-0.009 yg/£
total inorganic-P. Sawyer's pioneering work in Wisconsin (1947)
indicated the potential for nuisance growth of algae if early
spring concentrations in a lake exceeded 0.3 yg/£ inorganic-N
and 0.01 ug/& soluble-P (MA-743). Typical Lake Brandt concen-
trations have been in the vicinity of 1.0 yg/& inorganic-N and
0.05 yg/a ortho-P (the major inorganic P-form). Despite Lake
Brandt's somewhat nutrient-rich state, neither stands of aquatic
macrophytes nor nuisance algal blooms have developed. The prob-
able critical factor in this case is the extremely turbid nature
of the water. Photosynthesis is probably limited to the upper
2% feet (the photic zone depth) of the water column.
The STORM model (RA-R-667) results indicate that nitrogen
and suspended solids loadings will decrease, and phosphorus loadings
will increase as a result of the proposed action. Studies con-
cerning nutrient concentration and the trophic state of lakes
(SC-A-468) indicate that phosphorus is the most important macro-
nutrient for biological growth, and changes in the N:P ratio can
result in changes in species dominance in lake phytoplankton
communities. Increasing phosphorus concentrations coupled with
decreasing nitrogen concentrations will lower the N:P ratio
accordingly. This change may promote the growth of nitrogen-
fixing blue-green algae such as Anabena, an alga responsible for
nuisance "blooms". The lower turbidity associated with decreased
non-settleable solids loads to Lake Brandt will also tend to
promote the occurrence of niusance algal blooms. Thus Lake Brandt
will probably become more eutrophic, with the proposed action
accelerating this process somewhat. Water quality problems
such as offensive taste and odor associated with decomposition of
algal blooms may be expected to increase. Unit processes for
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removing taste and odor are not present at the Greensboro water
treatment plants.
5.1.6 Biological Components
The environmental effects of the proposed action on
terrestrial and aquatic biota in the Horsepen Creek area must
be evaluated with regard to the existing conditions of these
communities. Short-term direct effects will stem from construction
along pipeline routes. Indirect effects will occur as a result
of urbanization in newly sewered areas. It is assumed, however,
that this growth would occur with or without the proposed action.
5.1.6.1 Land
Direct Effects
The proposed construction of a 76,000 foot interceptor
system in the Horsepen Creek basin will disturb about 131 acres
(assuming a 75-foot right-of-way). The loss of riparian wood-
lands along this route will be the main impact of the proposed
action. Low growing grasses, herbs, and shrubs will revegetate
the streambank after construction is complete.
Wildlife which presently utilize the riparian habitat
along the proposed interceptor routes will temporarily with-
draw from the noise and general human disturbance which accompany
construction. Nesting sites or activities of some riparian birds
and mammals will be destroyed or interrupted by construction,
especially if construction takes place during the spring breeding
season. A few individuals, such as leopard frogs, ribbon snakes
or golden mice, will be killed as a direct result of construction.
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Removal of these animals should not have any lasting effect on
area populations. Because construction will proceed in a linear
fashion down the creek, only a relatively small area will be
disturbed at any given time. Some of the species which leave
these areas because of construction disturbance will return after
completion of the sewer line and revegetation of the disturbed
area. Since the trees will not be allowed to re-establish them-
selves over the right-of-way, only the grassland animal species
will repopulate the area. The forest species will be permanently
displaced.
Indirect Effects
The indirect environmental effects of the proposed
action on terrestrial flora and fauna will stem from urbanization
in newly sewered, previously rural areas. Fragmentation of
existing wildlife habitats will increase. Native vegetation will
be replaced with urban species and wildlife will withdraw from
the Horsepen Creek area due to increased human disturbance and
loss of suitable habitat.
5.1.6.2 Water
Direct Effects
Siltation of Horsepen Creek due to erosion from con-
struction areas is the primary impact anticipated from the pro-
posed action. Colloidal solids will be transported downstream
to Lake Brandt. Settleable solids may remain in the creek,
altering the substrate somewhat until a storm event moves these
particles into the lake. Benthic and other predominantly
sessile organisms may be adversely affected by the increased
suspended solids. The direct effects of construction are
expected to be temporary and of no significance to existing aquatic
populations.
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Indirect Effects
Urbanization in the Horsepen Creek basin is expected
to decrease base flows and increase pollutant loads to Horsepen
Creek. Significant reduction in base flow rates may threaten
the perennial nature of this stream causing fragmentation and
loss of existing aquatic habitat. Small fish populations may
become impounded if this occurs. Urban runoff and increased
septic tank use in the basin are expected to increase BOD levels
and decrease dissolved oxygen levels. In general, deterioration
of the high quality aquatic habitat now present is expected. The
degree of deterioration will be determined by specific develop-
mental pressures and land use measures enacted to preserve Horsepen
Creek itself.
Increased lead concentrations due to urban runoff may
threaten fish populations in Horsepen Creek and Lake Brandt.
Fish populations may be impaired if lead (Pb) concentrations exceed
30 yg/£ (NA-199). Concentrations higher than this have been
observed in Lake Brandt near the dam and the Horsepen Creek arm
of the lake. A persistent increase in lead levels over present
may result in a reduction in species diversity. In general,
urbanization of the Horsepen Creek area will favor pollution-
tolerant species and restrict the habitat of less tolerant
species.
5.1.6.3 Sensitive Areas
No rare/endangered terrestrial plant, animal, or
aquatic species or habitats critical for such species are cur-
rently known to occur along the proposed pipeline route. Most
of the areas have been previously disturbed by man's agricultural
or residential use. Some woodland acreage will be destroyed,
100
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but other similar habitat areas will remain. The small freshwater
marsh at the confluence of Horsepen Creek and Lake Brandt should
not be significantly affected by the project.
5.2 The Man-Made Environment
5.2.1 Land Use
The proposed action presents an interesting situation
from a land use perspective. Constant throughout this analysis
has been an assumption that 18,700 people will live in the
Horsepen Creek basin in the year 2000. That population repre-
sents a growth of 10,620 people from the 1975 population of 8,080.
The purpose of this section is to project the effect the proposed
action will have on the land use pattern which will evolve in
serving those 10,620 people who will establish residences in
that basin.
If public sewage will not be available for future resi-
dential developments, septic tanks or other private systems will
have to be used. However, the proposed action will physically
accommodate approximately 12,000 people. There is no reason
to believe that the full capacity of that interceptor will not
be used by the year 2000. If that is true, approximately 4,000
(12,000 - 8,000) of the 10,620 projected to move into the basin
will be in the sewered subdivisions. Assuming 8 people per acre
for sewered areas in the Greensboro vicinity (derived from Table
11-31 in EN-R-618) an additional 500 acres will be developed
with sewers by the year 2000.
The remaining 6,620 people will have to be served by
private systems such as septic tanks. Guilford County requires
a lot size of approximately 1 acre for a septic tank. It is
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assumed that private systems will only be used by single-family
units (3.0 people per household). Therefore, 2206 acres of
residential development with septic tank will occur by the year
2000 under the proposed action.
Additional residential development in the Horsepen
Creek basin will amount to approximately 2700 acres (2200 + 500)
by the year 2000. It has been projected that under any sewage
plan 210 acres of commercial land and 150 acres of industrial
land will develop (EN-R-618). Thus, a total of 3050 acres will
be developed through the year 2000 under the proposed action.
The pattern of development should follow the trends
already established. The commercial and industrial developments
should occur primarily in the southwestern portion of the basin
near the airport and along Highway 421. Further subdivisions with
sewers will probably occur adjacent to the already sewered areas
and those areas now on septic tanks to be sewered under the pro-
posed action. This is so the costs of providing that service
will be minimized. This would include much of the area close
to New Garden Road in the central portion of the basin and along
the eastern boundary of the basin. Those developments utilizing
septic tanks will probably be in the northwestern portion of
the basin. Land costs should be somewhat lower further from the
city. This will be important when the cost of a 1-acre lot is
taken into consideration.
The land use pattern which should result in the Horsepen
Creek basin will be costly to accommodate from a public services
perspective. It costs more to provide essential public services
(transportation, utilities, schools, etc.) for a low density
pattern than it does for a high density pattern (RE-118). From
that perspective the proposed action has an adverse effect.
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The 3,050 acres projected to change to urban use through
the year 2000 are below the total 3,107 acres of area available for
unrestricted future growth (RA-R-667). While the calculations used
in these analyses are crude, it does appear that the proposed
action will serve the projected population of the basin without
encroachment upon environmentally sensitive areas. However, the
margin for error is slight. The planning officials of Greensboro
and Guilford Counties will have to prudently exercise the growth
control measures they have at their disposals to insure the pro-
tection of environmentally sensitive areas.
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CHAPTER 6
MITIGATING MEASURES
104
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6.0 MITIGATING MEASURES
Mitigating measures for all areas of the environment that
may be affected by this project are not discussed in this report.
Only water quality and land use are discussed here, as impacts
associated with these two areas will probably be the most signifi-
cant to the Horsepen Creek watershed. Many of the mitigating
measures discussed in Chapter 6 of the Greensboro EIS (EN-R-618)
are also pertinent to impact mitigation for proposed activities
in the Horsepen Creek basin; the interested reader is referred to
this companion document for additional mitigating measures not
addressed in this section.
6.1 Water Quality
The results of the discussion on effects of the proposed
action indicate that degradation of the Greensboro water supply
in Lake Brandt is the most serious adverse impact associated with
this project. Direct impacts related to construction of the
interceptor itself are minor if the erosion and sedimentation
control ordinance is adhered to. The major adverse impacts on
water quality are secondary effects associated with urbanization
of the Horsepen Creek basin. Mitigating measures to reduce these
impacts will be a function of growth management approaches to
development in the Horsepen Creek basin which are adopted and
administered, largely at the local level.
A comprehensive plan for growth management in the area
will be the most effective method of preserving water quality in
Lake Brandt. One explicit goal of this process must be minimiz-
ing water quality impacts as development proceeds in the Horsepen
Creek area. The remainder of this section addresses basic fea-
tures that should be implemented at the local governmental levels
as a part of this urban watershed development planning and protec-
tion program .
105
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A comprehensive water quality planning program should
be instituted in the Lake Brandt watershed area. Section 208
of the Clean Water Act was intended to provide for the creation
of such comprehensive water pollution control planning and man-
agement programs. These comprehensive programs address all signi-
ficant water pollution problems in an area and develop pollution
control strategies to deal with these problems. The EPA program
provides for two options for plan preparation responsibility:
local agencies representing each designated 208 Planning Area or
a state agency in the remaining undesignated areas. Greensboro
is not currently a designated local area. The preparation of a
208 plan in the Greensboro area would provide for a detailed
analysis of local water quality problems and potential manage-
ment programs. The. North Carolina Department of Natural Resources
and Community Development is currently preparing the statewide
208. Because of the importance of water quality planning in the
Horseperi Creek basin, DNRCD intends to shift priorities to ad-
dress the area in early 1979 (see appendix).
A storm water system encouraging storm water retention
and infiltration would minimize the predicted impacts of storm
water runoff on water quality. Ulitizing natural drainage pat-
terns where possible, as opposed to a concrete-lined drainage
system, is one method of accomplishing this objective. Natural
drainage slows storm water runoff allowing more time for infil-
tration, longer lag times to peak flows, and lower peak flow rates.
As a result, pollutant loads and erosion due to storm water flows
are reduced.
A water quality monitoring program for Horsepen Creek
and Lake Brandt should be implemented. Degradation of water
quality due to urbanization has already been observed in other
watersheds in the Greensboro area. Collection of good water
quality data is necessary in order to formulate sound management
decisions and pinpoint problem areas before they become critical.
106
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Development in the freshwater marsh at the confluence
of Horsepen Creek and Lake Brandt should also be specifically
restricted. Marsh ecosystems act as natural waste treatment
systems which require no maintenance.
Specific legal measures should be adopted to insure that
future tie-ins to the Horsepen Creek interceptor do not exceed
its design capacity. Enforcement of such a measure will be cri-
tical to maintenance of water quality in Horsepen Creek and Lake
Brandt. If the capacity of the system is exceeded, overflows of
sanitary sewage would jeopardize public health as well as water
quality.
Finally, strict enforcement of the Guilford County
septic tank ordinance will be vital to preservation of Horsepen
Creek and Lake Brandt water quality. This ordinance will be
instrumental in controlling the proliferation of septic tank resi-
dences in the area. Proper design and location of septic tank
systems, as well as control of the density of septic tanks in a
given area, will minimize deleterious impacts on water quality as
a result of this type of development.
Many of these measures are already in use or under con-
sideration by Guilford County. Protection of water quality in
the Horsepen Creek basin is, in large part, the responsibility
of local officiating bodies and citizenry. Whether the proposed
action results in degradation of Greensboro's water supply will
depend on the responsiveness of these groups at the local level
to the need for controlled growth management.
6 . 2 Lan d Us e
To insure that environmentally sensitive areas are
not encroached upon by residential developments in the Horsepen
Creek basin and that the land resource is used efficiently,
107
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Greensboro and Guilford County officials must plan for a particu-
lar growth scenario and implement controls to insure that develop-
ment follows the plan. The Master Plan currently under consi-
deration is a step in that direction. It is important, however,
that the potential water quality problems associated with urban
development are a major consideration in the development of this
plan.
The subdivision ordinance of Guilford County has con-
siderable authority to control the pattern of growth. Subdivi-
sions must have acceptable sewage systems, either private or
public. Those which will be private must meet the standards of
the County Health Department, thereby protecting the water quality
of Lake Brandt. Development in flood-prone areas is prohibited
by this subdivision ordinance. This should be sufficient to re-
strict development immediately adjacent to Horsepen Creek.
The zoning ordinance is one of the strongest tools avail-
able for implementing land use policy through the municipality's
inherent power to exercise reasonable control over property and
persons under its jurisdiction. Zoning ordinances can regulate
both the type and density of land use. To be most effective in
the use of this power, the zoning ordinance should be based upon
a master plan designed to achieve community land use goals and
objectives. A major goal in the Lake Brandt watershed should be
the protection of Greensboro's drinking water supply.
The stated policies of the Guilford County Board of
County Commissioners show that county officials recognize the
need for land use planning to protect a fragile environment.
The "Open Space Program" of January 1977 explicitly stated that
the natural and cultural environment must be protected during
the course of residential, commercial, and industrial develop-
ment. That same concern for balancing development interests with
108
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environmental considerations is present in the "Land Use Goals
and Policies" statement of Guilford County. It is hoped that
these goals and concerns will lead to the implementation of a
comprehensive program for the protection of water quality.
The acquisition of land by the local governments is one
means of conserving sensitive areas, limiting urban runoff, and
providing recreational opportunities. Some of the means available
to acquire such lands include:
1. Simple acquisition of land for recreation or conser-
vation. The acquisition of land can be accomplished
through purchase and lease-back arrangements with
an owner. Gifts of land are also possible from
citizens, groups, and corporations to municipal-
ities, conservancies, and other organizations.
2. Easements - the purchase of conservation easements
can be used to limit developmentin critical areas,
woodlands, wetlands, water supply recharge areas,
floodplains, and open spaces.
3. Multiple use of sewer rights-of-way - where possible,
multipurpose uses of interceptor rights-of-way
should be encouraged. These uses include bike
paths , hiking trails, and nature trails.
Many of the measures required to promote orderly develop-
ment of the Horsepen Creek area and preserve the water quality
of Lake Brandt already exist. Perhaps the one possibility which
would upset this balance would be subdivisions with sewage
treatment via lift stations to public or private package treat-
men! plant:s discharging to adjacent streams. High density
109
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residential development could be accommodated in that manner.
Lake Brandt's water quality might be threatened by a proliferation
of these developments. It may be necessary to prohibit that
type of private facility.
An extensive thoroughfare plan not providing for high
density population would be another way to guard against that con-
tingency. The thoroughfare plan should be coordinated with the
growth management plan now under consideration.
6.3 Cultural Resources
The major class of cultural resources which may be
jeopardized by the proposed action would be archaeological arti-
facts. Since the exact routes have not yet been determined, a
reconnaissance would be of limited value. Potentially affected
areas will be surveyed to determine the presence of possible
archaeological resources. This survey will be accomplished during
the Step 2 process and the survey plan, and results will be
subject to approval by the North Carolina State Historical
Preservation Officer and State Archaeologist.
110
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CHAPTER 7
PUBLIC PARTICIPATION
111
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7.0
PUBLIC PARTICIPATION
At the initiation of the EIS process, a public partici-
pation program was developed to insure public involvement in
all phases of the EIS. On November 10, 1976, a public meeting
was held to solicit public input on major issues which should
be covered in the EIS and to ask for nominations for an EIS Advisory
Committee. Soon after this meeting, the Advisory Committee was
organized. This committee included the following representatives
from governmental agencies, private organizations, and-groups
interested in the project:
Mr. Ray Shaw
Mr. Charles Mortimore
Mr. Gaston Faison
Mr. Brent A. Hall
Mr. Tom Routh
Mr. Thomas E. Hubert
Mr. Carl Loop
Mr. Lindsey Cox
Mr. Fred Clapp
Mr. Richard Rough
Mr. David Dansby
Mr. Herman Fox
Dr. Burley Webb
Mr. Gerard Gray
Mr. John Jezorek
Dr. .Ernest Lumsden
Ms. Jean Lumsden
Ms. Ellen Olson
Mr. Francis Steltzer
Mr. Bob Cole
Ms. Pat Walker
City of Greensboro
County Commissioners
Chamber of Commerce
PTCOG
Board of Realtors
Greensboro Citizens Association
North Carolina A & T University
Environmental Action Coalition
League of Women Voters
Rural/Suburban Community
The Sierra Club
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Ms. Betty Cone
Dr. Paul Lutz
Mr. R.L. Thomas
Mr. William Ashworth
Mr. S.T. Hoffman
Ms. Judy Huckabee
Mr. E.R. Lashley
Mr. J.B. Erwin
Mr. B.J. Battle
Ms. Ann Lineweaver
Mr. Herbert Reese
Mr. Jim Jobe
Mr. Bill Anderson
Mr. Tom Veal
Mr. Tom Duckwall
Mr. R.H. Souther
Mr. W.S. Griswold
Guilford County Advisory Board
for Environmental Quality
Concerned Citizens of McLeansville
McLeansville Community Council
Piedmont Council of Engineering
and Technical Societies
NAACP
GATEWAYS
McLeansville Merchants Association
Greensboro Jaycees
Audubon Society
Homebuilders Association
Input from the EIS Advisory Committees included the
following:
identify local planning objectives
identify study area issues
review existing conditions inventories
assist in the development of alternatives
assist in comparison and evaluation of
alternatives
The Modified No Action alternative discussed in this
EIS was developed by the EIS Advisory Committee.
113
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CO-582 Cooper, K. E., S. S. Roberts, and J. B. Funderburg,
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DA-227 Dawley, Charlotte, The Birds of Guilford County,
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EN-071 Environmental Protection Agency, Compilation of Air
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NO-115 North Carolina, State of, Div. of Wildlife Resources
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Raleigh, North Carolina, February 1972.
NO-120 North Carolina, State of, Dept. of Natural and Economic
Resources, Extinct, Endangered, and Threatened Vascular
Plants of Primary Concern, circa 1975.
00-004 Costing, H. J., "An Ecological Analysis of the Plant
Communities of Piedmont, North Carolina", Amer. Nat. 38,
1-126, 1942.
RA-R-406 Radian Corporation, Technical Reference Document Pre-
pared for Greensboro, North Carolina Wastewater Treat-
ment Facilities. EIS, Austin, Texas, 1977.
RA-R-667 Radian Corporation, Investigation of Water Quality
Impacts Related to_Development of the Horsepen Creek
Basin, Final Report, EPA Contract No. 68-01-3436,
Austin, Texas, August 1977.
RE-118 Real Estate Research Corp., The Costs of Sprawl. En-
vironmental and Economic Costs of Alternative Residen-
tial Development Patterns at the Urban Fringe, 1974.
SC-468 Schindler, D. W., "Evolution of Phosphorus Limitation
in Lakes", Science 195(1), 260-62, 1977.
116
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SI-138 Simmons, Clyde E., Sediment Characteristics of Streams
in the Eastern Piedmont and Western Coastal Plain Re-
gions of North Carolina, Raleigh, North Carolina,
U.S.G.S., 1975.
US-305 U.S. Fish and Wildlife Service, "Threatened or Endan-
gered Fauna or Flora, Review of Status of Vascular
Plants and Determination of 'Critical Habitat'",
Fed. Reg. 40(127), 1975.
US-517 U.S. Department of Agriculture, Soil Survey Staff, Soil
Taxonomy, A Basic System of Soil Classification for
Making and Interpreting Soil Surveys, Agricultural
Handbook No. 436, Washington, D.C., December 1975.
US-A-1806 U.S. Department of Agriculture, Soil Conservation
Service, North Carolina Guilford County Board of
Commissioners, and North Carolina Agricultural
Experiment Station, Soil Survey of Guilford County,
North Carolina, December 1977.
US-562 U.S. Department of Agriculture, Soil Conservation
Service, Guilford County Progressive Soil Survey,
Interim Report, Interpretations for all Soils Iden-
tified and Mapped in Guilford County, March 1973.
VA-157 Van Horn, Scott, Private communication, State of
North Carolina, Wildlife Resources Commission, Raliegh,
North Carolina, November 1976.
WE-304 Weiss, Charles M. and Edward J. Kuenzler, The Trophic
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117
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APPENDIX
118
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North Carolina Department of Natural
Resources &Community Development
James B. Hunt, Jr., Governor Howard N. Lee, Secretary
June 28, 1978
Mr. John White
Region IV Director
U. S. Environmental Protection Agency
345 Courtland Street
Atlanta, Georgia 30308
Dear Mr. White:
This letter acknowledges your proposed actions with respect to approval
of alternatives outlined in the Greensboro (Horsepen Creek) Environmental
Impact Statement. I could have enthusiastically supported a decision to
select the alternative providing service to the area for the 20-year
planning period as set forth in the federal guidelines. The alternative
providing for limited development that you have decided to approve is
not, in our opinion, the best decision in this case. However, in order
to allow this needed project to proceed while I do object, I will
not protest.
As outlined at the meeting on May 19, 1978, you stated the need for a
Wastewater Management Plan for the Horsepen Creek drainage basin. We
feel that the City and County are, in fact, planning to meet these needs,
but we believe that additional capability and expertise will be needed
to prepare such a plan. We, therefore, intend to shift priorities
within our 208 planning efforts to address that area in early 1979,
and will urge City and County cooperation with our 208 Planning Unit.
Without such teamwork, it will be impossible to prepare a Wastewater
Management Plan in which the local governmental units can take pride
and can use as the planning tool it is meant to become.
With kindest regards and best wishes, I am
Respectfully yours,
Howard WT"~Lee
Post Office Box 27687 Raleigh, North Carolina 2761 1 Telephone 919 733-4984
An Equal Opportunity Affirmative Action Employer
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