HomeMy WebLinkAboutSmall Area Plan 1995Stoney Creek Basin
Smaff Area Plan
Three Development Options :
Conventional, Density - Neutral, Neo- Traditional
Prepared by Students in the
Department of City and Regional Planning
University of North Carolina at Chapel Hill
Spring 1995
Stoney Creek Basin
Smafl Area Plan
Prepared for:
Orange County Planning Department
Prepared by:
Planning 223 Class, Spring 1995
Department of City and Regional Planning
University of North Carolina at Chapel Hill
Dan Baechtold
Jeffrey Bandini
Jeffrey Bowyer
Jennifer Clinger
Eric Fladager
Richard Kos
Donald Lang
Heidi Merkel
Kaoru Oka
Travis Pollack
Jean Robbins
Shannon Sexton
Ron Sissem
Tracy Swagler
Lauren Tedder
Jennifer Zadwick
Supervised b y:
Professor David Godschalk
Professor Philip Berke
Teaching Assistant Marion Clark
Acknowledgments
This report has been prepared by sixteen graduate students in the Department of City and
Regional Planning at the University of North Carolina at Chapel Hill, under the direction of
Dr. David Godschalk and Dr. Philip Berke, with assistance from teaching assistant Marion
Clark. At the request of the Orange County Board of Commissioners, the students in the
Planning 223 Land Use Workshop were given the assignment of evaluating three land use
alternatives in the Stoney Creek Basin Area. The design alternatives and report are intended to
assist the Stoney Creek Basin Planning Group, which was formed to prepare a small area land
use plan and implementation recommendations. The Planning Group is made up of members
of the Orange County Board of Commissioners, Planning Board, Economic Development
Commission, and School Board, Duke Forest, Triangle Land Conservancy, and representatives
from neighborhoods within the Planning Area. The formulation of the land use plan will,
require further study by the Planning Group, who will also be considering two development
alternatives proposed by the Orange County Planning Department. This document is intended
to provide a foundation on which future plans may be based.
The members of the Planning Workshop class would like to thank Professor David Godschalk,
Professor Phil Berke, and Marion Clark for their guidance and assistance throughout the past
semester. We would also like to thank everyone in the Orange County Planning Department
who took time to assist us, including Marvin Collins for his help with many of our questions,
and Miriam Coleman for quickly handling our many requests for maps. We also wish to thank
David Stancil, Don Belk, Slade McCalip, Gene Bell, and Mary Willis for providing help in
their areas of expertise. We would especially like to thank Randall Arendt of the Natural
Lands Trust for taking time from his busy schedule to critique the development options
presented in this report.
We hope that this report will be useful to the staff and to the Planning Group during their
small area planning process.
Stoney Creek Basin Small Area Plan
Executive Summary
This report is the final step of the first phase of a small area planning process for a portion of
Orange County, North Carolina. The report was prepared for the Stoney Creek Basin Planning
Group, comprised of local officials and residents of the basin, to help the group evaluate
development options for the basin. It describes three design alternatives for future development
in Stoney Creek Basin. The alternatives are:
a conventional development design, which would continue the subdivision patterns that
presently exist in the county,
an open -space or "density - neutral" design, which clusters lots so as to maximize the
preservation of open space and is based on principles developed by Randall Arendt and
others, and
a neo- traditional, transit- oriented design, which proposes a village core focused on a
rail station, utilizing concepts developed by Peter Calthorpe.
The report also assesses the expected impacts of each development concept on the resources
within the basin and services provided the county. The Planning Group will utilize the
information in this report, together with additional information to be provided by the Orange
County Planning Department in subsequent phases, to recommend a development strategy for
the Stoney Creek-Basin to the Orange County Board of Commissioners in 1996.
The Planning Process
The report begins with a suitability analysis. The purpose of the suitability analyis is to
determine which areas of the basin are suitable for development. Further, the process is used
to determine the appropriateness of a given tract of land for a specified use. The report
explains the decision making process for how each area of the basin is planned and the total
acreage of those areas. Each design team then identified features that could create potential
constraints or opportunities for their design. This analysis was facilitated by the use of the
county's geographic information system which allowed for computer - generated maps to be
created.
In next step, each design team created conceptual maps illustrating a potential layout for future
development, based on the preservation and development objectives of each alternative. The
preservation objectives noted specific environmental, historic, and /or cultural features to be
considered, while the development objectives focused on the design goals for the completed
development. For the conventional development alternative, general. objectives included the
protection of the residential character of the area, and providing density transitions from
existing neighborhoods. For the density - neutral alternative, objectives included preserving
50 % of the buildable land as permanent open space and locating lots adjacent to open space to
Stoney Creek Basin Small Area Plan
provide views and access to natural areas. For the neo- traditional alternative, objectives
included reducing automobile dependence, integrating land uses, fostering a sense of
community, and providing a village center at a transit stop.
Based on these objectives, each team designed conceptual maps. For the conventional
development team, this process led to the creation of two scenarios. The first scenario assumes
that future development will occur according to the underlying zoning of the area: one unit per
acre. The second scenario assumes that future development will occur at a range of densities,
with an average net density of one unit per 1.85 acres (the average density of major
subdivisions within Orange County). The density - neutral team also designed a scenario based
on an overall net density of one unit per 1.85 acres. Their design process involved several
steps, including the identification of conservation areas and the placement of lots and a trail
system to maximize access to preserved open space. The neo- traditional team used a proposed
light -rail transit station as the focus of their design. A village core was sited around the transit
station, consisting of commercial, office, and residential development at a net density of 22
units per acre. Residential neighborhoods were then created with densities decreasing from 7
units per acre to 1 unit per acre as distance from the core increased.
Each team projected the number of new residents and dwelling units that would be generated
by each design, as well as acreage by land use. The conventional development (scenario two)
and density - neutral designs will create slightly less than 900 new residential units in the Stoney
Creek Basin; the neo - traditional scenario will generate over 3,300 new housing units.
Similarly, the conventional development and density - neutral scenarios will generate roughly
2,100 new residents while the neo - traditional scenario is expected to generate approximately
7,900 residents. These data formed the basis of the impact analysis that followed.
The Impact Analysis
The final phase of the project was the impact analysis. The analysis includes an assessment of
the expected impacts on a number of local resources, including:
• the natural and historic resources of the basin (stormwater runoff, non -point source
(NPS) pollution, sedimentation, wildlife habitat, and natural character),
• local water and sewer service (water service, groundwater, sewer service, and septic
disposal),
• the transportation network in the basin and the related impact on air quality,
• the school system,
• provision of public safety services,
• parks facilities, and
• - the fiscal impact on Orange County's budget. - - - - - - -- --
Each design scenario was analyzed in terms of these issues, and the relative impact of each is
compared in a comprehensive impact analysis matrix. This format was selected to allow
evaluation between designs, not to provide an absolute measure of the impact.
Stoney Creek Basin Small Area Plan
The conventional designs have either a low or no impact on water quality, water and sewer
service, transportation and air quality and demand for new parks. They also have a medium
impact on wildlife habitat and preservation of natural character, groundwater, provision of new
school facilities, and the necessity to expand public safety services. Conventional development
has a high impact on the historic structures of the area. It has a small positive fiscal impact.
The density - neutral design has either a low or no impact on water quality, wildlife habitat and
natural character, sewer service, and new park facilities. It has a medium impact on
sedimentation, historic resources, pressure on school facilities, water service and groundwater,
septic disposal and public safety resources. It has a small positive fiscal impact. This design
has no high impacts.
The neo- traditional design is the most intense of the three design options since this design
accomodates more residential dwellings and more non - residential development than the other
alternatives. It has high impacts on most of the elements. The exceptions are with medium
impacts on transportation and low impacts on air quality, parks, groundwater, septic disposal
and historic resources. It has a substantial positive fiscal impact.
SLTND4ARY OF IlVOACTS
Impact Conventional
Stormwater runoff LOW
NPS pollution
LOW
Sedimentation
LOW
Wildlife Habitat
MEDIUM
Natural Character
MEDIUM
Historic Resources
HIGH
Water Service
LOW
Groundwater
MEDIUM
Sewer Service
NO IMPACT
Septic Disposal
LOW
Transportation
LOW
Air Quality -
--LOW - - -
Schools
MEDIUM
Public Safety
MEDIUM
Density- Neutral
Neo- traditional
LOW
HIGH
LOW
HIGH
MEDIUM
HIGH
LOW
HIGH
LOW
HIGH
MEDIUM
LOW
MEDIUM
HIGH
MEDIUM
LOW
NO IMPACT
HIGH
MEDIUM
LOW
LOW
MEDIUM
-LOW - - - -
- LOW- -- - - - - - --
MEDIUM
HIGH
MEDIUM
HIGH
Stoney Creek Basin Small Area Plan
Table of Contents
Executive Summary
Introduction.................... ............................... 1
Land Suitability Analysis ........... ............................... 5
Conventional Development ......... ............................... 13
DesignConcept ............... ............................... 13
Objectives .................. ............................... 14
Design Process ............... ............................... 14
Results.................... ............................... 16
Density- Neutral Development ....... ............................... 20
DesignConcept ............... ............................... 20
Objectives .................. ............................... 21
Design Process ............... ............................... 22
Results.................... ............................... 25
Neo- Traditional Development ....... ............................... 28
DesignConcept ............... ............................... 28
Objectives .................. ............................... 30
Design Process .............................................. 31
Results.................... ............................... 33
Impact Analysis ................ ............................... 36
Conclusions ................... ............................... 46
Bibliography .................. ............................... 48
Appendices................... ............................... 50
Appendix A: Natural and Historic Resources ........................... Al
Appendix B: Water and Sewer ..... ............................... 131
Appendix C: Transportation ...... ............................... Cl
Appendix D: Air Quality ........................................... D -1 -
Appendix E: Schools ........... ............................... E1
Appendix F: Public Safety ....... ............................... F1
Appendix G: Parks ............ ............................... G1
Appendix H: Fiscal ............ ............................... H1
Stoney Creek Basin Area Plan, v
Tables
Table 1: Conventional Development Scenarios ............................ 16
Table 2: Density Neutral Yield Analysis . ............................... 22
Table 3: Open Space vs. Developed Area in Density - Neutral Design .............. 25
Table 4: Neo- Traditional Design Development Projections .................... 33
Table 5: Baseline Data - Proposed Development Scenarios .................... 37
Table 6: Summary of Impacts ....... ............................... 38
Table 7: Calculation of Water Demand ...... .............................B2
Table 8: Calculation of Effluent Generation .............................. B3
Table 9: Morning Peak Hour Traffic Flows at Intersections .................... C3
Table 10: Capacity Conditions of Existing Intersections With Projected Traffic Flows ... C3
Table 11: Summary of Transportation Analysis Findings ..................... C4
Table 12: Summary of Traffic Mitigation Measures ......................... C5
Table 13: Projected Carbon Monoxide Emissions (NC 10 and New Hope Church Road) . D2
Table 14: Current School Capacities and Enrollments ....................... .E1
Table 15: Student Generation by Development Scenario ...................... E3
Table 16: Impacts on School Capacities . ............................... E4
Table 17: Number of New Officers Needed to Maintain Current Level of Protection .... F2
Table 18: Summary of Demands for Parks and Size of Proposed Parks ............ G3
Table 19: Summary of Size of Land Dedicated by Developers .................. G3
Table 20: Residential Fiscal Impact Analysis ............................. H2
Table 21: Non - Residential Fiscal Impact Analysis .......................... H3
Stoney Creek Basin Area Plan, A
Maps
Map 1:
North Carolina Vicinity Map .... ............................... 3
Map 2:
Orange County, Vicinity Map ... ...............................
4
Map 3:
Potential Planning Area ....... ...............................
7
Map 4:
Natural Areas .............. ...............................
8
Map 5:
Primary Constraints .......... ...............................
9
Map 6:
Development Constraints Conventional Design .......................
10
Map 7:
Development Constraints Density - Neutral Design .....................
11
Map 8:
Development Constraints Neo- Traditional Design .....................
12
Map 9:
Conventional Design Scenario I . ...............................
17
Map 10:
Conventional Design Scenario II ...............................
18
Map 11:
Conventional Neighborhood Design .............................
19
Map 12:
Density - Neutral Design ...... ...............................
26
Map 13:
Density - Neutral Neighborhood Design ............................
27
Map 14:
Neo - Traditional Design Concept ...............................
34
Map 15:
Neo - Traditional Design ...... ...............................
35
Map 16:
Neo - Traditional Design Perspective .............................
36
Map 17:
Neo - Traditional Design Perspective .............................
37
Stoney Creek Basin Area Plan, vii
Introduction
At the request of the Orange County Board of Commissioners, the students in the Planning 223
Land Use Workshop were given the assignment of evaluating three land use design alternatives
in the Stoney Creek Basin Area. The design alternatives and report are intended to assist the
Stoney Creek Basin Planning Group, which was formed to prepare a land use plan and
implementation recommendations for a small area of the county.
The 4,696 -acre Stoney Creek Basin lies within the three county area, including Orange,
Durham and Wake Counties, that makes up the Triangle region in central North Carolina (see
Map 1). It is located two miles southeast of the Town of Hillsborough and five miles north of
the towns of Chapel Hill and Carrboro in Orange County (see Map 2). The area is bounded
by Interstate 85 to the north and Interstate 40 less than one mile to the west and defined
primarily by the drainage basin of Stoney Creek. The edges of the planning area were drawn
to include entire properties, when lot lines extended beyond the boundary of the actual
drainage basin. The county has designated two Economic Development Districts directly to
the east and the west of the planning area.
There are currently 795 dwelling units in the planning area: 589 are single family detached
homes and 206 are mobile homes. The planning area has an estimated population of 2,135
residents as of April, 1995. The current land uses are rural residential and subdivision
development, rural buffer in the southern portions, limited commercial along main roads
(although there is a 33 -acre parcel zoned commercial on a secondary road), and agricultural.
There are 1,999 acres available for development in the basin.
Because of its proximity to existing and future employment centers and transportation, as well
as the available land supply, this area is expected to grow rapidly in the near future. A small
area plan is needed to manage growth in an appropriate manner, and this report .is designed to
provide a foundation for such a plan.
Three land use alternatives were studied by the workshop class:
1. Conventional Design Plan - based upon the use of existing zoning regulations and the
continuation of current development patterns.
2. Density - Neutral Design Plan - based upon envisioning cluster development as a
- strategy for the preservation of large open spaces and environmentally sensitive
land,utilizing general open space design principles proposed by Randall Arendt and others
as explained in Rural Rv T)esiQn (Arendt, 1994b) and Desi nin en STace Dev_elloments
in 'Russex County I)f- aware (Arendt, 1993) .
Stoney Creek Basin Area Plan, 1
3. Neo- traditional Design Plan - based upon establishing a mixed -use, rail- centered
village core with surrounding, interconnected neighborhoods, and fostering a strong sense
of community, utilizing principles proposed by Andres Duany, Elizabeth Plater - Zyberk,
Peter Calthorpe, and others as explained in Towns and Town - Making Princides (Duany &
Plater - Zyberk, 1991), The Next American Metropolis ( Calthorpe, 1993), and The
Pedestrian Pocket Rook (Kelbaugh, 1989).
The first part of this study consisted of creating a design concept for each of the three
scenarios. A suitability analysis provided a foundation for each of the conceptual designs
based on topography, vegetation, soils, surrounding land uses, roads, floodplains, and other
constraints. The text describes the design concepts, objectives, and land use estimates of each
proposed design plan. The accompanying maps illustrate the actual designs.
The second part of this study entailed an impact assessment of each of the three scenarios.
The analysis allowed the study group to explore the advantages and disadvantages of each
proposal and how each might affect the surrounding area, as well as the county. The
recommended strategies to mitigate the impacts are described in the appendices.
Stoney Creek Basin Area Plan, 2
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Land Suitability Analysis
A suitability analysis is a process used to determine the appropriateness of a given tract of land for
a specified use. When viewed collectively, the environmental and physical features of an area- -
such as the hydrology, geology, and biology- -yield insights into the types of uses suitable for a
particular parcel of land. Suitability analyses can be conducted for any type of land use being
considered for an area. For the purposes of this project, the suitability of land for residential uses
was the primary concern.
The following steps were employed in developing the suitability analysis for Stoney Creek Basin:
Step 1: Map the land available for development, including:
• land not included in established subdivisions
• large unused parcels
• parcels with minimal existing development (one building) that are at least 10 acres
in size and contiguous to large undeveloped tracts.
Areas unavailable for planning purposes were masked with a gray screen on the
planning map (see Map 3). Using the above criteria, it was determined that 1,999
acres were available for development.
Step 2: Map the various physical and environmental features to see where they are
located in the area. (see Map 4).These include:
• Duke Forest
• Stoney Creek
Step 3: Identify which of these land features may constrain development and develop a
Primary Constraints Map for use by all three design groups. The primary
constraints include:
• Streams and ponds
• 100 -year floodplains and wetlands
• Steep slopes (greater than 15 %)
• Natural areas and wildlife corridors
• Soils unsuitable for septic systems
Once all of these features were included on the Primary Constraints Map (see Map 5),
the areas without any constraints were shown in white and were considered optimal
for development.
Step 4: Map specific development constraints and opportunities for each design group.
All three design groups were concerned with general constraints such as floodplains
and steep slopes. Differences between group objectives, however, required varying
Stoney Creek Basin Area Plan, 5
degrees of focus on certain constraints.
The Development Constraints Map for the conventional design group included all of
the features on the Primary Constraints Map as well as power line easements and
existing water and sewer lines. (see Map 6)
The density- neutral design group categorized various constraints as primary and
secondary conservation areas. The primary conservation areas, which would remain
undeveloped, included unbuildable areas of Duke Forest, wetlands, 100 -year
floodplains, alluvial soils, steep slopes and power easements. The secondary
conservation areas included natural areas, wildlife corridors, historic sites, deciduous
forest, and pasture /farmland. (see Map 7)
The neo- traditional design, which relies more upon infrastructure extension, included
all of the primary constraints except soils unsuitable for septic systems and added
economic development. districts, power line easements, existing water and sewer lines,
and historic sites to their constraints map. Soils unsuitable for septic systems were not
included because the density of development created with a neo - traditional design
would necessitate sewer and water service. (see Map 8)
Stoney Creek Basin Area Plan, 6
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Conventional Development
Design Concept
The term "conventional development" refers to the type of neighborhood design that has
predominated in this country since World War H. Beginning in the 1920s with the invention and
spread of the automobile, people no longer needed to live near central cities or along railroad or
streetcar lines. The automobile enabled those working in the cities to live in country settings
farther away from the central cities. Property in these outer areas also cost less due to its distance
from the economic center, allowing people to afford larger lots. The result was the eventual
proliferation of these "suburbs" characterized by single - family homes on larger lots. The size of
these lots enabled and even necessitated, due to the dispersion of homes, the use of on -site septic
tanks and wells. Aesthetic and safety concerns in the residential areas also led to the design of
curvilinear streets and the use of cul -de -sacs. The post -World War II boom saw the proliferation
of these "American Dream" neighborhoods where privacy is highly valued.
The concept of zoning, which arose in the mid- 1920's, called for the separation of land uses for
health reasons and for the protection of property values. This complete separation from the retail
and office activities in the central cities appealed to suburban residents. To protect the quality of
life offered by these suburbs, local governments began implementing development guidelines
including building -to -lot ratios, setback requirements, and minimum lot sizes. The resulting
subdivision and zoning ordinances effectively institutionalized the development process and
product, making deviation difficult. For example, the Orange County zoning ordinances set
minimum lot sizes at one unit per acre.
Most of the existing residential neighborhoods in the Stoney Creek Basin incorporate the basic
principles of low - density, conventional development design. For instance, individual lot sizes
range from one acre to over ten acres per unit. Also, existing single - family and mobile homes in
the basin are served by on -site septic tanks and wells. All water supply and wastewater treatment
needs of new neighborhoods will be served similarly in this scenario.
Stoney Creek Basin Area Plan, 13
Conventional Development Design Objectives
Preservation Objectives
• Protect sensitive natural areas, including:
- wetlands
- flood plains
- steep slopes.
• Protect the character of the area defined
in part by: .
- Duke Forest
- the designated Rural Buffer
- historic areas.
• Preserve existing neighborhoods by:
- avoiding undue disruptions
- providing density transitions.
Design Process
Development Objectives
• Provide a range of housing, including:
- a range of densities
- a range of costs.
• Provide appropriate support structures,
including:
- a community park
- roads.
• Maintain the beauty and character of the
area by:
- ensuring that buildings are aesthetically
integrated with the topography
- encouraging conservation easements
and dedications to preserve natural
corridors
- limiting development in the Rural
Buffer.
Two design scenarios were developed to illustrate the continued application of conventional
development practices in the Stoney Creek Basin. The first scenario allows for intensive
residential development in the basin in'accordance with existing zoning ordinances (see Map 9).
En the second scenario, new residential development occurs at a density more consistent with that
of existing subdivisions in Orange County (see Map 10). Several assumptions were made in
developing the two design scenarios:
• New development in areas constrained by steep slopes ( >15 %), soils unsuitable for septic
tanks, floodplains, or wetlands must conform to applicable ordinances and guidelines.
• Within the Rural Buffer (RB), new development will occur at a density of no more than
one dwelling unit per two acres.
• An allowance of 15% is made to account for that portion of available land used for new
roads and infrastructure.
Stoney Creek Basin Area Plan, 14
• All new residential development will be serviced by individual water wells and septic
systems.
• The pattern of new residential development will likely resemble traditional single - family
neighborhood design (see Map 11 for neighborhood design).
• A 50 -acre community park is planned for the corner of N.C. 10 and New Hope Church
Rd.
• While zoning densities may change within the planning area, no land use rezoning is
anticipated (i.e., no rezoning of land from residential to commercial).
Additional assumptions were made to achieve the goals of each design scenario:
Scenario I: Build -Out at Highest Allowable Density
• Existing zoning (one dwelling unit per acre) in the planning area will not be altered. .
• The net density for new residential development in the planning area will be one dwelling
unit per acre.
Scenario II: Build -Out at Lesser Density
• The net density of new residential development in the planning area will be the same as the
current average net density for existing major subdivisions in Orange County (one
dwelling unit per 1.85 acres).
• The siting and density of new neighborhoods will account for natural constraints and take
advantage of natural features for recreational and aesthetic purposes where practical.
• The planning and design of new neighborhoods will take into account the existing
character of nearby areas.
Stoney Creek Basin Area Plan, 15
Results
The following table illustrates the two development scenarios anticipated under the conventional
development design:
Table 1: Conventional Development Scenarios
1 To calculate the total number of buildable dwelling units, Total Acreage is equal to the total undeveloped
acreage in the planning area (1,999 acres) less 33 acres for an existing commercial area and 50 acres for a planned
community park.
Stoney Creek Basin Area Plan, 16
Scenario I
Scenario H
Total Acreage'
1,916 acres
1,916 acres
Adjusted Acreage less Infrastructure
(15%)
1,629 acres
1,629 acres
Net Density of Planning Area
1 dwelling unit / acre
1 dwelling unit / 1.85 acres
Total Dwelling Units
1,629 units
879 units
1 To calculate the total number of buildable dwelling units, Total Acreage is equal to the total undeveloped
acreage in the planning area (1,999 acres) less 33 acres for an existing commercial area and 50 acres for a planned
community park.
Stoney Creek Basin Area Plan, 16
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eighborhood
Density - Neutral Development
Design Concept
"Density - Neutral" refers to a type of open space- oriented residential development that reserves
50 % of the buildable land as undivided, permanent open space. In a density - neutral
development, the same number of houses are built in a subdivision as would be permitted
under existing zoning, but the houses are clustered together on smaller lots to leave at least
50% of the land open. Half of the open space in such a development is left in a natural state,
while the other half can be used for more active recreation such as community greens, parks,
or ballfields. Density - neutral subdivisions are often described as "golf course developments
without the golf courses" (Arendt, 1994) .
Density - neutral developments allow residents immediate access to open space and natural areas
via tree lined sidewalks, trails, and greenways. The creation of formal greens and commons in
which neighbors can socialize also facilitates a greater degree of social interaction than is
typically found in a suburban neighborhood. Comparative studies show that property values in
such subdivisions appreciate faster than in conventional subdivisions, even though the lots are
typically smaller (Arendt, 1994a).
In addition, density - neutral designs allow lots to be placed with more consideration for
environmentally sensitive areas and other constraints. Thus, streams, trees, historic sites,
habitats, and other amenities can be preserved for the enjoyment of the residents and for their
intrinsic environmental resource value. For example, preserved natural areas provide wildlife
habitat, allow higher groundwater recharge rates than conventional subdivisions (due to
decreased impervious cover), and help reduce non -point water pollution by absorbing and
filtering runoff from developed areas that would otherwise be discharged into nearby
waterways. At the same time, lots can be sited away from land uses or activities that conflict
with residential development such as major roads or industrial areas.
A primary constraint to utilizing the density - neutral design approach in the Stoney Creek Basin
relates to land ownership. Density - neutral design works best on larger parcels of land where
greater flexibility is permitted in terms of siting of land uses. Many of the lots within the
Basin, especially in the area along Old Highway 86, are small in size. Therefore, a process of
lot consolidation or land compacts would have to be developed to allow small lots to be
combined into larger developable areas.
Stoney Creek Basin Area Plan, 20
Density - Neutral Development Design Objectives
• Preserve "primary conservation areas,"
including:
- floodplains
- wetlands
- steep slopes.
• Preserve 50 % of the remaining
buildable land for open space.
• . Protect "secondary conservation areas,"
including:
- lowland hardwood forests
- small tributaries
- unsuitable soils for septic systems
- historic areas
• Provide every household views of
natural open space.
• Provide social and /or recreational open
space within walking distance of each
household.
• . Provide vegetative buffers between
neighborhoods.
• Protect the character of the surrounding
area.
• Provide the same number of units on
the site as permitted under current
zoning regulations. ('This is where the
term "density - neutral" is derived.)
• Provide a range of housing types and
densities.
• Reduce engineering, construction, and
maintenance costs by implementing
environmental protection measures.
• Consider a combination of sewage
disposal and water supply alternatives
based on the unique features of each
neighborhood.
• Carefully consider site topography in
the siting of roads.
Stoney Creek Basin Area Plan, 21
Design Process
The density - neutral development design for Stoney Creek Basin (see Map 12) is the result of a
five -step process recommended by Randall Arendt and described in the following five
subsections.
Step 1: Perform a yield analysis
The yield analysis involves calculating the total number of lots permitted by existing
zoning. The number of units that would ordinarily be built on the site becomes the
number to be accommodated in the density - neutral design (Arendt, 1994a). For
Stoney Creek, the yield was calculated using 1.85 acres as the average lot size; this
figure reflects the averageJot size of major subdivisions within the county. The
following table illustrates the process for calculating the total number of lots that
could be created within the Stoney Creek Basin using this average lot size:
Table 2: Density Neutral Yield Analysis
The yield analysis shows that 899 lots could be created within the Basin. The next
four steps in the process involve development design.
Step 2: Identify potential open space areas
This step involves defining all open space to be preserved within the density - neutral
development. First, primary conservation areas, or land that cannot be built on, is
defined and mapped. In the Stoney Creek Basin, primary conservation areas consist
of floodplains, steep slopes, and wetlands. These unbuildable areas, generally
located along Stoney Creek, create a spine of open space through the central portion
of the property. Next, secondary conservation areas, or land which contains
2 To calculate the total number of buildable dwelling units, Total Acreage is equal to the total undeveloped
acreage in the planning area (1,999 acres) less 42 acres for a planned community park.
Stoney Creek Basin Area Plan, 22
Density - Neutral Design
Total Acreage'
1,957 acres
Adjusted Acreage less Infrastructure (15%)
1,664 acres
Net Density of Planning Area
1 dwelling unit / 1.85 acres
Total Dwelling Units
899 units
The yield analysis shows that 899 lots could be created within the Basin. The next
four steps in the process involve development design.
Step 2: Identify potential open space areas
This step involves defining all open space to be preserved within the density - neutral
development. First, primary conservation areas, or land that cannot be built on, is
defined and mapped. In the Stoney Creek Basin, primary conservation areas consist
of floodplains, steep slopes, and wetlands. These unbuildable areas, generally
located along Stoney Creek, create a spine of open space through the central portion
of the property. Next, secondary conservation areas, or land which contains
2 To calculate the total number of buildable dwelling units, Total Acreage is equal to the total undeveloped
acreage in the planning area (1,999 acres) less 42 acres for a planned community park.
Stoney Creek Basin Area Plan, 22
significant natural or cultural resources, is defined and mapped. In the Stoney
Creek Basin, secondary conservation areas consist of hardwood forests, open
meadows, historic sites, and soils unsuitable for septic tanks. Once primary and
secondary conservation areas have been mapped, the areas most suitable for
development become evident because of their lack of resource constraints.
Step 3: Locate sites for residential uses
Identifying potential house site locations entails maximizing the number of lots that
will have views of or access to open space. No lots are placed in primary
conservation areas and, to the extent possible, lots are placed around but not in the
secondary conservation areas. An optimal design would give each house direct
access to an open space, either in front or back. Easements located between lots,
especially at the end of cul -de -sacs, are included to ensure maximum access to open
space for all homes on a street.
These design concepts are reflected in the density - neutral design for the Stoney
Creek Basin. No development is proposed within primary conservation areas. An
effort was made to minimize development within secondary conservation areas and
the cultural resources within them - -such as historical sites -- around which the land
use plan was designed. The number of lots located next to stream corridors, open
meadows and wooded hilltops were maximized to provide views, access to open
space, and access to environmental amenities. Easements at the end of cul -de -sacs
were included to facilitate access to open space areas. The design also reflects an
effort to design around adverse site features; setbacks from the railroad and
Interstate 85 were maintained to reduce potential noise and safety conflicts.
Lot sizes vary from approximately one - quarter to three - quarters of an acre. There
are two primary reasons for variable lot size. First, smaller lots provide the
flexibility needed to design around unique amenities and resources while
maintaining the ability to meet density requirements. Second, variation in lot size
enhances marketing potential by increasing the variety of available products at
different prices.
Step 4: Design roads and trails
Once open space has been identified and potential house sites located, the fourth
step involves determining the layout of street and trail systems. Road rights -of -way
are largely dictated by the location of home sites and by the need to respect existing
topography.
The design of the road network consists largely of curvilinear streets and cul -de-
sacs. This design approach allows maximum sensitivity to topographic features and
Stoney Creek Basin Area Plan, 23
responds to the irregular layout of house sites created to take advantage of natural
amenities and topography. Internal roadway design was complicated by the lack of
existing access to major roadways throughout the Basin. A desire to minimize
wetlands disruption caused by road construction, the inability to create road access
across the railroad, and steep slopes in the northern part of the site were primary
constraints that influenced internal roadway design.
The proposed trail system was designed with three goals in mind; 1) to link the
Stoney Creek corridor and other intermittent stream corridors to the rest of the site;
2) to connect areas of common open space to the stream corridors and other
common open space; and 3) to ensure adequate access to the trail system from all
home sites. Trail surfaces will vary depending on their intended use. A mixture of
paved and unpaved surfaces are proposed: unpaved trails will be located primarily
within the stream corridors and forested areas, while paved trails will predominate
in high traffic areas such as common open spaces.
Step 5: Draw lot lines
The last step in this process simply involves drawing lot lines to delineate
ownership. Because lots in density - neutral developments tend to be smaller than
conventional subdivisions, lot lines can, as necessary, be drawn close to one side of
the buildings (zero lot line setback) to provide larger, usable side yards on the other
side of the building. In general, though lot sizes are small, each home is still
provided with views and access to open space. This design feature effectively
increases the "perceived" size of each lot (see Map 13 for neighborhood design).
Stoney Creek Basin Area Plan, 24
Results
The following chart summarizes the relationship between open space and developed area under
the proposed design. The requirement that at least 50 % of the site be kept in open space has
been met.
Table 3: Open Space vs. Developed Area in Density- Neutral Design
Stoney Creek Basin Area Plan, 25
Acreage
Percentage
Total Area in Open Space
1,171 acres
59
Primary Conservation Areas
302 acres
- --
Secondary Conservation Areas and
Other Open Space
869 acres
- --
Total Developed Area
828 acres
41%
Total Area Available for Planning
1,999 acres
100 %
Stoney Creek Basin Area Plan, 25
r
1
Map 13:
Density - Neutral
Neighborhood Design
® - 100 Year Fioodpiain
- Mixed and Conifer Forest
- Deciduous Forest
- Meadow
Developed Area
-
Power Easement
- Historical Site
Lake
Neo- Traditional Development
Design Concept
Interest in neo- traditional design has been growing in recent years as the negative effects of
low- density sprawl are becoming more apparent in the form of traffic congestion, loss of open
space, and social isolation. The primary aim of neo- traditional development is to. reproduce
the strong feeling of community found in older, established neighborhoods (usually pre -World
War II) by creating pedestrian- friendly, mixed -use environments. This goal can be
accomplished by incorporating the following principles:
• Reduced automobile dependency
• Integration, not separation, of land uses
• Inward neighborhood focus, not dispersal of destinations
• Streets as focal points, not mere thoroughfares
• Revival of social interaction and shared community vision
• Flexible design guidelines, not rigid engineering standards
Most neo - traditional developments have different design features from those found in
conventional subdivisions. Examples of neo - traditional neighborhoods are Seaside, FL,
Kentlands, MD, and Southern Village in Chapel Hill, NC. Some of the more prominent
features of neo - traditional design are:
• Street design - narrow, grid or modified grid patterns with tree -lined sidewalks
• Parking - on- street, behind buildings, or in alleys, not in parking lots or in household
garages facing streets
• Open Space - neighborhood parks, public greens, and protected floodplains
• Building setbacks - shallow or none
• Commercial/Office areas - main street and neighborhood areas, not strip centers and
malls
• Land uses - mixed -uses, heterogeneous.
Essentially an outgrowth of neo - traditional design, transit- oriented development attempts to
- further reduce automobile dependency by creating a more urban, densely - populated
environment which can support rail or other forms of public transportation. While most neo -
traditional developments try to recreate small town America, transit - oriented design attempts
to create a new suburban style of living. For example, neo - traditional developments have an
average net density of 3 to 7 dwelling units (du) per acre, while - transit oriented developments
Stoney Creek Basin Area Plan, 28
call for average net densities of 10 to 25 du to support transit. Advocates of this type of
development include Peter Calthorpe, a California architect whose design standards have been
applied in Laguna West, CA and Andres Duany and Elizabeth Plater - Zyberk, the designers of
the neo- traditional towns Seaside, FL and Kentlands, MD.
Applying the principles and design features of neo - traditional design results in a development
pattern centered around a village core, featuring a vibrant mix of -shops and residences (see
perspective p 36). Surrounding the core are residential neighborhoods with densities decreasing
as distance from the core increases. The development design can accommodate a variety of
single and multi - family options. Public gathering spaces, human- scaled streetscapes, and a
reasonably consistent architectural theme will link neighborhoods throughout the development.
This design group was directed by the Orange County Planning staff to generate a transit -
oriented design focused on a potential Triangle Transit Authority (TTA) rail station.
Stoney Creek Basin Area Plan, 29
Neo- Traditional, Transit- Oriented Design Objectives
• Locate development outside of
Reduce dependence on automobiles by
environmentally sensitive areas to
providing for transportation
protect the integrity of:
alternatives, including:
- floodplains
- expanded bus service
- wetlands
- potential TTA rail service
- wildlife habitat corridors
- extensive pedestrian and bike paths.
- the designated Rural Buffer.
• Maximize public access to natural areas
• Protect existing neighborhoods by:
from all neighborhoods.
- buffering existing and proposed
neighborhoods
Foster a sense of community by:
- providing density transitions.
- establishing a mixed -use village core
- designing attractive streetscapes
- linking neighborhoods visually and
physically.
• Emphasize topographical features by
utilizing ridge tops as focal points.
• Provide a variety of housing, including:
- single- family homes
- apartments above shops
- multi - family dwellings.
• Provide public amenities and services,
_ including:
- parks and greenways
- public schools and day care
- emergency services.
Stoney Creek Basin Area Plan, 30
Design Process
The neo- traditional development design for Stoney Creek Basin is the result of a five -step
process described in the following five subsections.
Step 1: Determine the most suitable location for the village core.
Using the maps generated in the land suitability analysis and site visits, the design
team analyzed several potential village core locations. Sites were assessed based on
proximity to the rail transit corridor defined by the Triangle Transit Authority
(TTA) and proximity to existing main roads. Other criteria included contiguity of
developable land, environmental constraints, and potential for water and sewer
extensions. The site chosen is located in the north central portion of the planning
area on a hillside of the Stoney Creek valley and adjacent to the Southern Railroad
tracks. A civic area has been identified between the village core and NC 10 for a
park and ride lot, regional park, and other institutional uses.
Step 2: Identify other neighborhood sites.
The suitability of neighborhood locations surrounding the village core is based upon
proximity to the village core. Neighborhoods are centered around historically or
topographically significant focal points (see Map 15) . Moderate - density
neighborhoods are sited within 3/4 mile of the village core in order to support the
proposed rail transit station and to provide an adequate market for the commercial
uses in the village core (see Map 14).
Step 3: Establish strong connections between focal points.
To link the surrounding neighborhoods to the village core, and to enhance the sense
of community within the village, strong visual and pedestrian connections are
established. Connections are designed to take advantage of, and highlight, the
existing topography (see perspective p 37) .
Step 4: Develop independent pedestrian and auto networks.
New road alignments are designed to provide access between neighborhoods and the
village core, and to structure each neighborhood around its focal point. Existing
alignments are preserved wherever feasible. Sidewalks and connecting greenways
will be used as pedestrian and bicycle routes. Greenway path alternatives are
_- identified by highlighting_ linear environmentally sensitive features and assessing__
their suitability as pedestrian linkages between neighborhoods and the village core.
Duke Forest is considered as a potential link between the western parcels and the
village core, creating a circular greenway system.
Stoney Creek Basin Area Plan, 31
Step 5: Define neighborhoods.
Neighborhoods are designed to support the village core as well as to create distinctive
characters within each area. Wherever possible, greenways are used to define neighborhoods.
Each neighborhood is centered around a focal point, such as a hilltop or historic site. Specific
design guidelines will be proposed for each neighborhood, in order to establish and maintain
its unique character.
Stoney Creek Basin Area Plan, 32
Results
The following table illustrates the development anticipated under the neo- traditional design
scenario:
Table 4: Neo- Traditional Design Development Projections
Residential Density
Dwelling Unit /
acre
Gross Acreage
Net Acreage*
Total Dwelling
Units
Low Density
1
800
600
600
Medium Density
7
370
278
1,946
Mixed Use
7
is
11
79
High Density
22
41
31
682
Total Residential
1,227 acres
920 acres
3,307 units
Other Land Uses
Commercial
10
Civic Areas
29
Transit Stop
1
Parks, Greenways and Utility
Easement
731
Total Project Acreage
1,999
* Net acreage is the gross acreage adjusted 25 % to allow for roads, sidewalks, and alleys.
Stoney Creek Basin Area Plan, 33
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Impact Analysis
The second phase of the Stoney Creek Basin study focused on a qualitative assessment of the
impacts created by each of the three development scenarios. This section contains a summary
narrative and matrix of the impacts created by each scenario. It is followed by appendices that
provide a detailed description of each of the impacts, how they were measured, relevant data,
and proposed mitigation strategies.
Each design is rated by the magnitude of the impact brought to bear on various resources. The
ratings used are high, medium, and low. Additionally, the designs are ranked relative to each
other. The resources considered by the study include natural and historic resources, including
encroachment on Stoney Creek, wetlands, large forested areas, and wildlife habitats; the
impact on water quality caused by impervious surface and density of development; the degree
of alteration to the natural aesthetics of the site; and the impact on historic structures.
Infrastructure concerns, such as extension of water and sewer supply and the demand placed
on existing and future supply (including groundwater as a source of drinking water), were also
considered as impacts. Also, the impacts brought by transportation improvements and effects
on air quality are considered relative to each design scenario.
Only Scenario II of the conventional design was analyzed because of the likelihood that new
conventional development in the basin would resemble the conditions outlined in this scenario.
The baseline data in Table 5 were used to compare the .three design scenarios.
Impact Summary Narrative
Conventional Design Impacts
Conventional development has either a low impact or no impact with regard to water quality,
water and sewer service extension, transportation improvements and resulting air quality, and
the demand for new parks. It has a medium impact on wildlife habitat and natural character,
provision of new school facilities, and the necessity to expand public safety services.
Conventional development greatly impacts the historic structures of the area by failing to
preserve either the structures or their surrounding contexts. (See the Impact Matrix Table 6.)
Contributing to the advantages of conventional development, the large lot sizes reduce amounts
of impervious surface, mitigating some of the detrimental effects of stormwater runoff and
non -point source pollution. Water and sewer service extensions from Hillsborough are not
currently planned for most of the Stoney Creek basin area, thus making site specific septic
disposal and water supply (wells) necessary. However, on -site systems may be impractical
Stoney Creek Basin Area Plan, 38
given the poor soil percolation of some parts of the area. Also, conventional development
could potentially cover wellhead protection areas vital for groundwater recharge.
Conventional development has the lowest impact on transportation improvements, only
requiring traffic signals on two intersections. Although the community park proposed by
Orange County will be adequate to serve the entire planning area, conventional development
will likely not provide needed neighborhood parks.
The conventional design has a greater impact on native wildlife habitat. The dispersed nature
of conventional development threatens fauna that need deep forest environments. This natural
environment can be partially, but not fully, replaced through plantings required by the Orange
County Subdivision Ordinance. This design will also place pressure on New Hope Elementary
School District and could require new elementary and middle school facilities. The planning
area lies within the Eno and New Hope Volunteer Fire Department service radii, and is
covered by Orange County Emergency Medical Service. Small increases in personnel may be
warrented; response times should not increase significantly. This design will have a small
positive fiscal impact.
Density- Neutral Design Impacts
The density - neutral design option has either low or no impacts on water quality, wildlife
habitat and natural character, water and sewer service, supply, and disposal, transportation and
air quality, and the demand for parks. It has a medium impact on sedimentation during
construction, pressure on school facilities, and public safety resources. The density - neutral
option has no high impacts.
Density - neutral development is more concentrated than conventional design, making erosion
control and sedimentation during construction more problematic. This design option allows
for a larger buffer along Stoney Creek and provides an abundance of open space throughout
the planning area. This will help offset the greater concentration of lots, and therefore
impervious surfaces, near the creek. The concentrated nature of this development also has the
benefit of preserving significant stands of hardwood trees and wetland buffers, taking
advantage of the natural amenities. Each home has an immediate view of either forest land or
meadows and easy access to recreational open space. Water and sewer extensions are possible
to some residential clusters and may be desirable since there is poor soil percolation for septic
systems in some areas. This design will require new elementary and high school facilities.
Impacts on transportation and air quality, demand for new parks, and public safety resources
are the same as for conventional development. This design has a small positive fiscal impact.
Neo- Traditional/Transit- Oriented Design Impacts
The neo- traditional design is the most intense of the three scenarios, with 75 % more dwellings
and an additional one million square feet of non - residential development. Due to its larger
Stoney Creek Basin Area Plan, 39
population and higher density, the neo- traditional design creates high impacts on virtually all
elements except groundwater quality, septic disposal, air quality, and parks, where the impacts
are low. There is a medium impact on transportation.
Building more houses and businesses adds larger areas of impervious surface with high rates of
stormwater runoff and increased pollutant loads into Stoney Creek. Construction of the village
core and surrounding high density development will require a great deal of land disturbance
and threats of sedimentation to the water courses. The village core will also require the most
extensive transportation improvements with new traffic signals on three intersections and
additional turn lanes at the intersections of NC 86 with both New Hope Church Rd. and
NC 10. Water and sewer service extensions from Hillsborough are necessary. These
infrastructure extensions would require about 33 % of the current sewage treatment capacity
and about 40% of the future water supply of Hillsborough. The additional population also
creates the need for new elementary, middle and high school facilities, additional
neighborhood and pocket parks, and an increase in public safety resources in the form of a
public safety center and additional police.
Increased human presence displaces much of the wildlife. However, the design does leave the
wildlife corridor and floodplain intact. The design takes advantage of the natural topography
by using ridge tops as focal points and highlighting the good views. Historic structures are
integrated into the design and recommended for restoration. This design scenario has a
substantial positive fiscal impact.
Stoney Creek Basin Area Plan, 40
Table 5: Baseline Data - Proposed Development Scenarios
3 Available acres, conventional development, equals total undeveloped acreage less 33 acres of an existing
commercial area and 50 acres for a planned community park.
4 Available acres, density- neutral development, equals total undeveloped acreage less 42 acres for a planned
community park.
5 Available acres, neo- traditional development, equals total undeveloped acreage
6 Neo- traditional development reserves more land for infrastructure because of the dense nature of the design;
urbanized land requires a higher percentage of land be given over to infrastructure.
7 Household size; in people per household, represents an estinate based on current household sizes within the
townships in which planning area is located.
8 Based on 0.43 children per household.
Stoney Creek Basin Area Plan, 41
Conventional
Density - Neutral
Neo-Traditional
Available Acres
1,9163
1,9574
1,9995
Infrastructure
15%
15%
25 %6
Dwelling Units (du)
879
899
31307
Average Density
1 du/1.85 acre
1 du /1.85 acre
1 du/.28 acre
Household Size'
2.4
2.4
2.4
Population
2,110
2,158
7,937
Children'
378
387
1,422
Land Use:
Residential
all single family
all single family
mix of single family
and multi - family
Commercial
none
none
350,000 sq ft office
650,000 sq ft retail
29 acres civic
Open Space
limited preservation
extensive preservation
some preservation
3 Available acres, conventional development, equals total undeveloped acreage less 33 acres of an existing
commercial area and 50 acres for a planned community park.
4 Available acres, density- neutral development, equals total undeveloped acreage less 42 acres for a planned
community park.
5 Available acres, neo- traditional development, equals total undeveloped acreage
6 Neo- traditional development reserves more land for infrastructure because of the dense nature of the design;
urbanized land requires a higher percentage of land be given over to infrastructure.
7 Household size; in people per household, represents an estinate based on current household sizes within the
townships in which planning area is located.
8 Based on 0.43 children per household.
Stoney Creek Basin Area Plan, 41
Table 6: Summary of Impacts
Impact Area
Conventional
Density - Neutral
Neo-Traditional
Water Quality
Stormwater Runoff
LOW
LOW
HIGH
Larger lots will help minimize
Abundant open space will help
High development density and
effects of increased
minimize effects of increased
significant impervious surfaces,
stormwater runoff into Stoney
stormwater runoff into Stoney
especially near Stoney Creek,
Creek.
Creek.
will require costly mitigation to
control increased runoff.
Non -point Source
LOW
LOW
HIGH
Pollution
Larger lots may filter
Abundant open space and large
Greatly increased human activity
pollutants, but may be a
buffers along Stoney Creek will
in Village Core, just north of
problem if yards are grassed
help filter pollutants.
Stoney Creek, will significantly
(fertilizer may wash into
increase pollutant levels.
creek).
reserves.
Sedimentation
LOW
MEDIUM
HIGH
Low- density development will
Clustered development will
Construction of Village Core and
spread out construction of
make control of erosion during
high- density residential will
houses, allowing greater
construction more difficult.
require grading of steep slopes,
chance of controlling erosion
which could cause significant
on construction sites.
erosion and probable
sedimentation into Stoney Creek.
Historic Resources
HIGH
MEDIUM
LOW
Low- density development will
Historic resources will not be
This design uses the historic
fail to preserve historic
highlighted, but will be
structures and the surroundings
structures or their
preserved as much as possible.
as focal points which necessitates
surroundings.
preservation and restoration.
Wildlife Habitat
MEDIUM
LOW
HIGH
Expansive development
Development will allow for
Wildlife corridor will be left
throughout site invades
abundant and continuous open
intact but extensive use of land
-
wetlands and forest wildlife
spaces, including hardwood
and high density of human
habitat.
forests, but will take away some
presence will significantly affect
deep forestland and habitat
wildlife habitat.
edges.
Natural Character
MEDIUM
LOW
HIGH
Design does not take
While this development will hold
The design maximizes the site's
advantage of natural character
about the same number of homes
natural topography, but the -
of the site. However, the
as the conventional development,
extensive use of land will greatly
large lots will allow
the design takes advantage of the
alter the natural character of site.
preservation of many of trees
natural amenities on the site,
in the area.
including viewsheds, meadows,
and forests.
Stoney Creek Basin Area Plan, 42
Table 6 (continued): Summary of Impacts
Impact Area
Conventional
Density - Neutral
Neo- Traditional
Water and Sewer
Water Service
LOW
MEDIUM
HIGH
Given low density, water lines
If necessary water lines could be
Infrastructure can be extended.
will not be extended from
extended to cluster
Demand would be about 40% of
Hillsborough, necessitating the
developments. Hillsborough has
Hillsborough's future supply
use of individual wells.
adequate supply. Demand of
capacity. Demand of 1,118,775
292,175 gpd.
gpd.
Groundwater
MEDIUM
MEDIUM
LOW
(as a source of
Good supply is probable.
Good supply is probable. May
Groundwater is not a viable
drinking water)
May be adequate as primary
be adequate as primary source,
option. Must be provided with
source, but on -site testing
but on -site testing required. If
water service.
required. If not, water service
not, water service may be
may be required.
required.
Sewer Service
NO IMPACT
LOW
HIGH
Infrastructure cannot be
Infrastructure can be extended to
Infrastructure can be extended.
extended and individual septic
some clusters and treatment
Would require about 33 % of
disposal systems must be used.
capacity is available. Effluent
Hillsborough's current treatment
generation of about 262,957 gpd.
capacity. Effluent generation of
about 906,200 gpd.
Septic Disposal
LOW
LOW
MEDIUM
Septic disposal should be a
Individual septic disposal
Septic disposal is not a viable
viable option provided that lot
systems will not be permitted on
option for higher intensity uses,
sizes are modified to ensure
lots smaller than 3/4 acre.
but may be viable for areas
that adequate drain field areas
Easements attached to each lot
designed for low density
exist on each.
smaller than 3/4 acre and located
residential development.
within common open space can
be established to ensure adequate
drain field area for individual
systems. Conuuunity septic
systems are also a viable
disposal option.
Stoney Creek Basin Area Plan, 43
Table 6 (continued) : Summary of Impacts
Impact Area
Conventional
Density - Neutral
Impact Area
Transportation
LOW
LOW
MEDIUM
Intersections at N.C. 86 &
Intersections at N.C. 86 & New
Intersections at N.C. 86 & New
New Hope Church Road and
Hope Church Road and N.C. 86
Hope Church Road and N.C. 86
N.C. 86 & N.C. 10 will
& N.C. 10 will require traffic
& N.C. 10 will require traffic
require traffic signals.
signals. Intersection at N.C. 10
signals and additional turning
Intersection at N.C. 10 & New
& New Hope Church Road will
lanes. Intersection at N.C. 10 &
Hope Church Road will not
not require improvements.
New Hope Church Road will
require improvements.
require a traffic signal only.
Air Quality
LOW
LOW
LOW
Carbon monoxide
Carbon monoxide concentrations
Carbon monoxide concentrations
concentrations will be well
will be well below EPA
will be well below EPA
below EPA standards.
standards.
standards.
Schools
MEDIUM
MEDIUM
HIGH
The elementary schools will
Additional elementary and high
Additional elementary, middle
exceed capacity by 117
school facilities will be required.
and high school facilities will be
students, and the high school
Elementary schools will exceed
required. Elementary schools will
will exceed capacity by 89
capacity by 121 students, and the
exceed capacity by 637 students,
students. The middle schools
high school will exceed capacity
middle schools will exceed
will remain 48 students under
by 92 students. The middle
capacity by 194 students, and the
capacity.
schools will remain 46 students
high school will exceed capacity
under capacity.
by 371 students.
New Hope elementary school
Again, the New Hope
Again, the New Hope elementary
district, which comprises most
elementary school district will be
school district will be most
of the planning area, will be
most heavily impacted.
heavily impacted.
most heavily impacted.
Adjusting district lines may
ease some of the burden.
Stoney Creek Basin Area Plan, 44
Table 6 (continued): Summary of Impacts
Impact Area
IPublic Safety
Police/Fire/Rescue
I Parks
IRevenue/Fiscal
Residential
Non - Residential
Conventional
MEDIUM
Moderate increases in police
personnel needed in order to
maintain current levels of
service: 7 (annexation by
Hillsborough) or 4 (Orange
County jurisdiction).
Planning Area lies within Eno
and New Hope Volunteer Fire
Department service radii, and
is covered by Orange County
Emergency Medical Service
(EMS). Small increases in
personnel may be warranted;
response times should not
increase significantly.
LOW
Demand for parks is low.
One community park will be
provided, but no neighborhood
parks will be created.
POSITIVE
Minimal increase in County
and School District employees
(2 %). Annual net fiscal
surplus of $180,700.
POSITIVE
Annual net fiscal surplus of
$400,000.
Density - Neutral
MEDIUM
Moderate increases in police
personnel needed in order to
maintain current levels of
service: 7 (annexation by
Hillsborough) or 4 (Orange
County jurisdiction).
Planning Area lies within Eno
and New Hope Volunteer Fire
Department service radii, and is
covered by Orange County
EMS. Small increases in
personnel may be warranted;
response times should not
increase significantly.
LOW
Demand for parks is low. One
community park will be
provided. No neighborhood
park is provided, but this
demand will be met by available
open space.
POSITIVE
Minimal increase in County and
School District employees (2 %).
Annual net fiscal surplus of
$176,400.
N/A
No proposed non - residential
development
Neo- Traditional
HIGH
Large population increases and
concentrations warrant the
construction of a new public
safety center near the Village
Core area. The center should
combine locally - oriented police,
fire and rescue personnel trained
to serve the new "downtown"
area. In order to maintain current
levels of police protection, 25
new officers would be needed
(Hillsborough annexation) or 16
new officers if Orange County
retains jurisdiction.
LOW
Demand for new parks is high.
The demand will be met by
provision of one community park,
three neighborhood parks, and
several pocket parks.
POSITIVE
Large increase in County and
School District employees (8
Annual net fiscal surplus of
$831,700.
POSITIVE
Total retail/office development net
annual fiscal surplus of over
$2,500,000.
Stoney Creek Basin Area Plan, 45
Conclusions
The Stoney Creek Basin is an area under significant growth pressure, due to its appealing rural
character and convenient access to Durham, Chapel Hill, and the Research Triangle Park. The
small area planning process is an attempt to shape this growth in a manner that is sensible and
responsive to the needs of residents and landowners in the area.
Following the charge of the Orange County Board of Commissioners, the Planning
Applications 223 class of the Department of City and Regional Planning at the University of
North Carolina prepared three alternative land use designs to assist the Stoney Creek Basin
Planning Group in developing a small area plan. The outcomes revealed what the basin might
look like under conventional design patterns and also presented two recent design concepts in
planning that are both innovative and forward - looking. One of these concepts, density - neutral
design, is based on the idea of designing for both development and conservation; while the
other concept, neo- traditional design, is centered on the premise that a return to traditional
town planning principles is a prudent alternative to sprawl development. These designs and
their impacts were presented to the planning group at two meetings at New Hope Elementary
School in April, 1995.
The three alternative designs presented in this report do not represent mutually exclusive
outcomes. Components of each design could be modified and combined to form the basis of a
successful plan. For instance, a neo - traditional development does not have to be transit -
oriented. The neo - traditional development presented in this report is centered around a
regional rail transit station, proposed by the Triangle Transit Authority. High densities are
required to support a rail transit station. A composite plan, however, may contain a neo -
traditional development with much lower densities than those needed to support rail transit.
An example of such a development is Southern Village in southern Chapel Hill. Southern
Village consists of about thirteen hundred homes and a village core with shopping and offices,
on approximately 300 acres of land. Thus, a composite plan might include neo - traditional
development, which may or may not be centered around a transit stop. The same plan could
incorporate the density - neutral concept by including several open -space neighborhoods.
Moreover, conventional neighborhood design may be appropriate for other areas of the basin.
It is also important to note that the impacts presented in this report are based on projected
outcomes for conceptual designs.. More specific impact assessments will depend on the actual
development pattern of the basin and the site - specific layout of that development.
The contribution of this class concludes Phase I of the planning. process for the Stoney Creek
Basin Small Area Plan. This report will serve as a foundation for Phase II in which the
Planning Group will consider these alternatives, together with two additional designs from the
Stoney Creek Basin Area Plan, 46
Orange County Planning Department, and review the positive and negative aspects of each
design towards the goal of developing a composite plan. We hope that this report will provide
a sound basis for developing a high - quality small area plan for the Stoney Creek Basin.
Stoney Creek Basin Area Plan, 47
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Stoney Creek Bassin Area Plan, 49