HomeMy WebLinkAboutAgenda - 06-07-2016-13-5 - Information Item - Memorandum - Development Impacts on Rural Areas INFORMATION ITEM 1
PLANNING & INSPECTIONS DEPARTMENT
Craig N. Benedict, AICP, Director
Administration 131 W. Margaret Lane
(919) 245-2575 Suite 201
(919) 644-3002 (FAX) ORANGE COUNTY P. O. Box 8181
www.orangecountync.gov NORTH CAROLINA Hillsborough, NC 27278
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MEMORANDUM
TO: Board of County Commissioners
FROM: Craig Benedict, Planning & Inspections Director
DATE: June 7, 2016
SUBJECT: INFORMATION ITEM — Development impacts on rural areas
ATTACHMENT 1: Adopted Growth Management System Map, November 5, 2003
ATTACHMENT 2: NCDOT Level of Service D Standards for Systems Level Planning
(excerpt)
Please accept this memorandum in response to a request from Commissioner Barry
Jacobs for an explanation on the identification/measurement of transportation impacts.
Specifically Commissioner Jacobs wanted a breakdown of how we
regard/regulate/gauge traffic impacts in the rural and/or urban areas of the County.
Preamble: Roads under county planning jurisdiction have been under the maintenance
control of the North Carolina Department of Transportation (NCDOT) since 1932 and
therefore their responsibility and authority will in most cases take precedence over local
county government.
Existing Regulations
The Growth Management Systems was adopted on November 5, 2003 as a tool
allowing for the differentiation between the various required review processes and
development standards for projects located in either urban or rural settings (Attachment
1). The intent of the Growth Management Systems process, ultimately, was to require a
heightened level of project review based on a project's location and its anticipated
impact(s) in that setting.
The UDO also establishes standards for the completion of a Transportation Impact
Analysis (TIA) for development projects meeting set criteria. A TIA is intended to
provide an analysis of a development project's impact, if any, on existing transportation
networks.
The UDO requires a TIA for the following:
1 . All Conditional Use and/or Conditional Zoning District permit applications
regardless of anticipated daily trips or location within the County (Section 2.9 of
the UDO),
2
2. Any proposed land use (i.e. permitted or special use) having an estimated traffic
generation exceeding 800 traffic trips per day regardless of location within the
County,
3. Within rural designated areas of the County, as depicted on the adopted Growth
Management Systems Map (Attachment 1), for subdivision projects proposing 41
or more individual parcels (Section(s) 2.9 and 7.2.3 of the UDO, and
4. Within urban areas, as depicted on the adopted Growth Management System
Map (Attachment 1), for subdivision projects proposing 80 or more lots
(Section(s) 2.9 and 7.2.3 of the UDO).
Per Section 6.17.2 (B) of the UDO staff may also require any `special use permit,
subdivision, or site plan' application to be accompanied by a TIA where a `road capacity
or safety issue' is identified. Please note there are currently no criteria within the UDO
for staff to utilize in deciding/determining same. Adopting defensible and discernable
criteria/threshold for Sec. 6.17.2. (B) may be useful to avoid being arbitrary or capricious
in our decisions making processes. While this might provide clarification, it will not
necessarily result in the requirement for related road improvements.
NCDOT TIA Review Policy
In those instances where a TIA is required, staff provides a copy to NCDOT for its
review and comment. NCDOT considers the results of the document but is not
governed by its findings. Ultimately decisions related to required public road
improvements (i.e. internal and external on a given project) are made in accordance
with the NCDOT Policy on Street and Driveway Access to North Carolina Highways
(i.e., the `Driveway Manual').
Capacity and Improvements
Section 6.17.5 of the UDO requires a capacity analysis as part of a TIA, to determine
the adequacy of the roadway system to accommodate the proposed additional traffic.
Road improvements can be required to address capacity issues.
The capacity of a road facility is defined as the maximum hourly rate at which vehicles
reasonably can be expected to traverse a section of a road during a given time period
under prevailing roadway, traffic, and control conditions (e.g., signal phasing).
The Trip Generation Manual (used by transportation professionals conducting TIAs)
states that single family residential trips are approximately ten (10) vehicle trips per
residence per day. The Manual also includes potential solutions/improvements to be
incorporated either within or external to the proposed development when traffic
mitigation needs are identified through the TIA.
Level of Service (LOS) is a quality measure describing operational conditions within a
traffic stream (speed and travel time, etc.). LOS is defined with letter designations
ranging from A to F that can be applied to both roadway segments and intersections.
LOS A represents the best operating condition and LOS F the worst. NCDOT defines
capacity on rural two-lane highways as LOS D, which is when a road facility has poor
conditions with very minimal service. LOS D has a maximum density of generally
around 42 passenger cars per mile per lane (Source: NCDOT Level of Service D
Standards for Systems Level Planning).
2
3
Rural two-lane undivided highways are classified by NCDOT as `other major
thoroughfares' if they are a US or NC route and `minor thoroughfares' or `rural two-lane
highways' if they are a secondary/local route. Within the Piedmont area of North
Carolina, LOS D Standards for these types of roads is generally between 14,300 and
16,500 vehicles per day, depending primarily on lane width and speed limit. NCDOT
tables providing more detailed information are provided in Attachment 2).
The NCDOT Driveway Manual states that a TIA may be required for developments with
an estimated trip generation of 3,000 vehicles per day or greater. A TIA may also be
required by NCDOT for:
• Proposed accesses within 1,000 feet of an interchange;
• In the vicinity of a high accident location;
• On a major arterial roadway;
• Where there is involvement with a median crossover;
• Where highway improvements are in the Transportation Improvement Program
(TIP):
• If there is involvement with an active roadway construction project: or
• At the discretion of the District Engineer.
Improvements more restrictive than NCDOT's are unlikely to meet the warrants under
the NCDOT Driveway Manual due to the study threshold being so much higher than
Orange County's.
Existing Development Conditions
There are three basic types of subdivisions within the UDO: Exempt (by statute), Minor
and Major. Minor and Exempt subdivision development is much more prevalent in
Orange County than Major subdivisions. From 2008-2015 the average lots per year for
Major, Minor and Exempt subdivisions were 25.43, 46.38, and 57.25, respectively, and
admittedly part of the recession years. TIAs are required by the UDO according to the
location and size of subdivision, as well as the type of development application required.
All of the Minor and Exempt subdivisions will continue with only the requirement of a
NCDOT driveway permit, with no warrants being met for improvements. These
subdivisions are prevalent in the County compared to the larger subdivisions.
The TIA threshold within urban areas in Orange County is 3.75 times more restrictive
than the state. Orange County has made revisions to lower the threshold for required
TIAs within rural areas. This might be informative to the evaluation of a development
request, but will likely not accomplish required improvements because NCDOT will not
enforce TIA recommendations in conflict with the Driveway Manual, and when there is
capacity on the roads. We will continue to work with NCDOT to institute improvements
acceptable to their guidelines and that of the County.
3
Growth Management System Attach J ment1
Urban and Rural Designated Areas
Urban Designated-Property located within Transition Areas as identified in the Land Use Plan.
Rural Designated-Property not located in Urban Designated areas
49
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Hillsborough
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Legend
Urban Designated (3.6%)
.I‘ Rural Designated (84.4%)
Rural Buffer
City Limits
40—� Extra-Territorial Jurisdiction
Chapel Hill
6.4% Chapel Hill/Carrboro Transition
(Not part of Growth Management
t.-
System)
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Carrboro (74:-D.
2.3% 0 1 2 3
Miles
1 inch = 3 miles
Orange County Planning and Inspections Department
GIS Map Prepared by Brian Carson.
Growth Management System adopted by BOCC 11/5/03
Printed 5/23/2016
5
Attachment 2
MG OD T F 8
TRAM BPORTATIC? N PLANNt1%4G BRAN G1--J
II
Level of Service D Standards for
Systems Level Planning
Updated 10/14/2011
6
Piedmont Level of Service D Standards
for Other Major Thoroughfares *
55 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 12900 14600 15100 14200 15900 16500
11 foot lanes 12500 14100 14600 13700 15400 16000
10 foot lanes 12000 13600 14100 13300 14800 15400
9 foot lanes 11600 13100 13600 12800 14300 14900
45 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 12200 12700 14600 13300 13800 16000
11 foot lanes 11800 12300 14100 12900 13300 15500
10 foot lanes 11400 11900 13600 12400 12900 14900
9 foot lanes 11000 11400 13100 12000 12400 14400
35 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 11100 11600 12700 12900
11 foot lanes 10700 11200 12300 12500
10 foot lanes 10400 10800 11900 12000
9 foot lanes 10000 10400 11400 11600
25 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 11000 12700
11 foot lanes 10600 12300
10 foot lanes 10300 11900
9 foot lanes 9900 11400
Uses "Principal Arterials" Facility Type in NCLOS
* Decrease in Lane Width Capacity calculated via 2000 Highway Capacity Manual
lane-width adjustment factor for saturation flow rate j'll
See Appendix D1 for HCM 2000 Urban Arterial Equations
Use Appendix D3: Piedmont Major Thoroughfare Inputs for adjustments
NOTE: Lane Width is adjusted downward by 3.33% per less foot of pavement
11 Updated 10/14/2011
7
Piedmont Level of Service D Standards
for Minor Thoroughfares *
55 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 12900 14600 15100 14200 15900 16500
11 foot lanes 12500 14100 14600 13700 15400 16000
10 foot lanes 12000 13600 14100 13300 14800 15400
9 foot lanes 11600 13100 13600 12800 14300 14900
45 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 11700 12200 14600 13100 13200 16000
11 foot lanes 11300 11800 14100 12700 12800 15500
10 foot lanes 10900 11400 13600 12200 12300 14900
9 foot lanes 10500 11000 13100 11800 11900 14400
35 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 10200 10200 11700 12700
11 foot lanes 9900 9900 11300 12300
10 foot lanes 9500 9500 10900 11900
9footlanes 9200 9200 10500 11400
25 MPH 1 Lane Per Direction 1 Lane Per Direction WCLTL
Urban Suburban Rural Urban Suburban Rural
12 foot lanes 10000 11300
11 foot lanes 9700 10900
10 foot lanes 9300 10500
9 foot lanes 9000 10200
II
Uses "Principal Arterials" and "Minor Arterials" Facility Types in NCLOS
* Decrease in Lane Width Capacity calculated via 2000 Highway Capacity Manual
lane-width adjustment factor for saturation flow rate
See Appendix El for HCM 2000 Urban Arterial Equations
Use Appendix E3: Piedmont Minor Thoroughfare Inputs for adjustments
NOTE: Lane Width is adjusted downward by 3.33% per less foot of pavement
16 Updated 10/14/2011
8
Level of Service D Standards for Rural 2-Lane Highways
Coastal 2-Lane COASTAL
Highway Standard Minimum Standard Maximum
12-Foot Lanes 10500 12700*
11-Foot Lanes 10000 14700*#
10-Foot Lanes 9200 12000
9-Foot Lanes 7700 10700
Piedmont 2-Lane PIEDMONT
Highway Standard Minimum Standard Maximum
12-Foot Lanes 10300 12400*
11-Foot Lanes 9900 14300*#
10-Foot Lanes 9000 11800
9-Foot Lanes 7500 10500
Mountain 2-Lane MOUNTAINS (Level)
Highway Standard Minimum Standard Maximum
12-Foot Lanes 10200
11-Foot Lanes 9800 12100*
10-Foot Lanes 8800 11700 14000*#
9-Foot Lanes 7400 10300
Mountain 2-Lane MOUNTAINS (Rolling)
Highway Standard Minimum Standard Maximum
12-Foot Lanes 9600 12100*
11-Foot Lanes 9100 14000*#
10-Foot Lanes 8200 11100
9-Foot Lanes 6300 9800
Uses"2-Lane Highways" Facility Type in NCLOS
*All capacities calculated based on HCM 2000 procedures using HCS software. Under some conditions,
two-lane highway capacity is not affected by lane width.This occurs where capacity is governed by
Percent Time Spent Following rather than by Average Travel Speed.
#Best-case/Maximum conditions are less likely to occur where lane widths are below 11 feet.
Use caution before selecting "Maximum"values for 9-ft or 10-ft lanes.
See Appendix Fl for HCM 2000 2-Lane Highway Equations
Use Appendix F2: Coastal Rural 2-Lane Highway Inputs for adjustments
Use Appendix F3: Piedmont Rural 2-Lane Highway Inputs for adjustments
Use Appendix F4: Mountain (Level) Rural 2-Lane Highway Inputs for adjustments
Use Appendix F5: Mountain (Rolling) Rural 2-Lane Highway Inputs for adjustments
18 Updated 10/14/2011