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5
Recommendations
5.2 Roadways
In order to determine which roadways would be recommended for adding lanes, modi-
fying intersections, or would require new, parallel roadways, a number of factors were
considered. Each of the following factors (Figure 5.2) was considered in the context of the
whole, and their importance may vary according to the specific context of the surround-
ing environment.
One important concept is the travel demand model,
which allows analysts to “test” various roadway and
land use configurations, and then see the results in
terms of traffic on the simulated “streets.” However,
this is only one aspect of transportation planning.
Too often, the travel demand modeling exercise has
served as a substitute for common sense. Constraints
produced by financial limitations, context of the road-
way, topography, and desirable land use interactions
should serve a much greater role in determining what
can and should be recommended. In this Plan, the
travel demand model results were blended with pub-
lic and staff input, as well as physical considerations to
create a more balanced set of recommendations.
As with the review of the Existing Conditions (Section
Three), the recommendations for roadway and in-
tersection improvements are described briefly in the
body of this section in terms of their north-south and
east-west connectivity, as well as connecting ma-
jor destinations within Morrisville. However, detailed,
street-by-street and intersection recommendations are provided in
Appendices E and F, which can be used for guiding development
requirements.
North-South Corridors
As shown in Figure 5.3, NC 54, I-40, Davis Drive, and NC 55 are all
forecasted to be operating under severe traffic congestion in 2035,
with the volume-of-cars-to-capacity-of-roadways (V/C ratio) at 1.0 or
greater. This congestion is predicted despite the numerous planned
capacity improvements. Figure 5.4 provides a summary of the results
of the Triangle Regional Model (TRM), and several significant points
are noted below:
•
NC 540 (Western Wake Freeway), six new lanes of freeway ca-
pacity, is lightly used;
•
Davis Drive, widened to six lanes, still has significant delay on
the roadway throughout its length in the Morrisville area;
•
NC 54 is assumed to be four lanes instead of the current two;
•
New McCrimmon Parkway Extension has been constructed;
and
•
New separated-grade overpasses of NC 54 and the Norfolk
Southern Railroad at both Airport Boulevard and McCrimmon
Parkway are included.
The fact that the TRM is still predicting significant delays on nearly all
major north-south roadways despite massive capacity increases veri-
fies a truth that has been borne out in many places at many times over
the past decades: simply adding more capacity in a growing area
is a temporary solution at best, and needs to be carefully weighed
against the goals of the community.
Figure 5.2 General Roadway Improvement Factors
Existing Congestion Levels
a
How long does it take now?
Future Congestion Levels
a
How long will it take later?
Public and Plan Advisory Com-
mittee Involvement
a
What did the public say about this?
Number and Type of Accidents
a
How many preventable accidents have there
been?
Land Use Interactions v. Street
Functions Now
a
What is the land use in the area like now?
Land Use Interactions v. Street
Functions Later
a
What will the land use in the area be like later?
Bicyclist and Pedestrian Facilities
and Safety
a
What are the conditions for cycling & walking?
Future Modes of Travel
a
What will the street be used for later (transit riders,
cyclists, walkers?)
Roadway Geometry
a
Are there physical or natural constraints?
NC 54, Davis Drive, I-40, Airport Boulevard, and Aviation Parkway
show high congestion levels in this forecasted map in spite of large
improvements. Sample modeling suggests that even with more lanes
(six) and additional capacity on NC 540 and other roads, congestion
levels will remain high in the peak periods of the day. Levels indicated
are derived from volume-to-capacity ratios. New roadways shown
as present/connected in the map were included in the model.
Figure 5.4 Level of Service Summary for Travel Modes for Transporta-
tion Scenarios (Derived from the Triangle Regional Model)
Location/Roadway
Model Year
Car
Bike Ped
p
o q
Morrisville-Carpenter Road
2035 trend
F
E
E
2035 proposed
E
C B
NC 54
2035 trend
F
F
F
2035 proposed
E
C A
Aviation Parkway
2035 trend
B
F
E
2035 proposed
B
B
B
Airport Boulevard
2035 trend
C E
E
2035 proposed
C B
B
Town Hall Drive
2035 trend
C D A
2035 proposed
C E
B
McCrimmon Parkway
2035 trend
E
E
D
2035 proposed
D C B
Davis Drive
2035 trend
F
E
E
2035 proposed
F
B
B
For a definition of level of service categories, please see Figure 3.3.