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5
Recommendations
5.0 R
ecommendations
5.1 Land Use and Transportation Relationships
Nearly everyone alive requires transportation – to get to food, buy shoes, attend a church,
have a baby, or get to work to pay for it all. It is easy to overlook transportation and the
systems that comprise it simply because we live in an era where the “friction” of travel is
pretty low; the distance we can cover in one hour is a multiple of the distance traveled in
several days just 150 years ago.
This section will briefly cover several concepts that will provide a sound underpinning for
the current discussion of transportation recommendations. Especially important are con-
nections between what happens within street rights-of-way (the area owned, usually, by a
state or public agency) and on the adjacent lands. Following is a quick overview of major
concepts that should be considered in addition to traffic performance and safety issues;
each topic’s importance varies according to the situation and specific context of the
area in which a transportation facility resides.
Access vs. Mobility
One of the most-established concepts in the modern era of road-building is that roadways
should have a lot of capacity for vehicles or provide good access to adjacent land par-
cels – but not both on the same road (see Figure 5.1). Freeways allow high-speed travel for
many cars at the same time; the local street where we reside carries few cars but allows us
to park a car close to the front door. Often, there is pressure to develop alongside major
thoroughfares that should be carrying many cars but with restricted access. This creates a
situation with a lot of traffic congestion and the potential for safety problems, or “conflict
points.” Managing access, through shared driveways, medians, street / driveway spacing
standards, and other techniques, helps to conserve the traffic capacity of the roadway
system.
Build It and They Will Come
There is no urban area in the United States that has been both growing rapidly and has
managed to construct enough roadway capacity to create free-flowing traffic conditions
in peak rush hours. Simply widening the streets, while important, is insufficient to create
easy traffic movement for a long period of time in our region. Redundancy (having more
than one option for how to get to your destination) is a key to an efficient transportation
system because it allows travelers to choose an alternative path when one is stopped (e.g.
accident or construction). Alternatives are also critical for police, fire and other public
services to quickly reach all areas in town. An efficient system allows for short trips to be
made by walking, bicycling or by car without taking up capacity on thoroughfares and
longer trips to be made with a transit option for many people, rather than the few served
by transit currently. Providing information to travelers before they set out and removing
accidents in a timely manner will help reduce delays. Regardless, traffic congestion is a
fact of life: just as water seeks low ground, people will certainly seek out lightly-used routes
to save time. Providing a good system is not just a nice thing to do for a few people, but
critical to providing an efficient transportation system.
What Has Been May Not Always Be
Twenty-five years ago, few people owned cell phones, in part because they were as a
big as a football. Twenty years ago, people said that individual recycling programs would
never work because no one would take the time to separate out their trash into bins and
take them down to the curb. Ten years ago, the idea of tolling roadways to help pay for
them was a foreign idea in North Carolina, and one that was received with near-universal
hostility. As fuel prices continue to surge with no end in sight, as sustainable energy prac-
tices gain momentum all over the state and the country, we would be well-advised to
remember these changes and not plan for the last trend but instead prepare for the next
one. Transit use has been increasing in the first decade of the new century: Wake County
now turns away 25% of requests for transit service due to limited capacity, and C-Tran,
Cary’s transit service, has seen 50% annual growth over the past three years. The incredible
increases in the demand for road capacity – as well as the inability of governments to pay
for their rapidly escalating costs – may soon reach a zenith, a concept that even a few
years ago was unthinkable.
Get Creative
In part as a result of changes in lifestyle, awareness of environmental issues, oil shortages,
and other external factors, we are capable of considering bolder changes in crafting this
Plan. Coordinated signal systems that provide signal priority to buses; multi-purpose road-
ways that move cars, bicycles, pedestrians, and transit vehicles with similar ease; “new
urbanist” designs that are calling for lower speeds and greater connectivity between
neighborhoods; traffic calming facilities in neighborhoods; street designs that respect the
context of the natural and built environments; greenways and sidewalks as commuter cor-
ridors to job center; allowing expanded home occupations in residential areas; these are
just a few of the possibilities that are now becoming a part of mainstream transportation
planning and engineering.
The following recommendations take into account a number of considerations, many
more than can be derived from a computer travel model or straightening out a bend in
the roadway. The roadway, transit, and bicycle/pedestrian recommendations are shown
separately, but serve each other and the adjacent lands they touch.
To choose doubt as a phi losophy of l i fe i s ak in to choos ing
immobi l i ty as a means of transportat ion
- Yann Martel, The Life of Pi
Figure 5.1 Access vs. Mobility
There is an inherent tradeoff between land ac-
cess and mobility in roadways. Local streets with
many driveways and lots of intersections contrast
with freeways that have limited access ramps but
increased speeds. Streets that were intended to
provide high degrees of mobility often slow down
with street intersections, driveways, and traf-
fic signals. This degradation causes the access/
mobility curve to shift towards more land ac-
cess, but causes problems for people who want
to reach their destination safely and quickly.
About theTravel Demand Model
TheTriangle Regional Model (TRM) models all of
theTriangle Region, includingWake, Durham, and
parts of surrounding counties.TheTRM is a type
of four-step assignment model, whereby trips are
artificially estimated from a land use description
containing information on population and employ-
ment by five basic types.This information is distrib-
uted to various destinations, called traffic analysis
zones (TAZs).TheTRM then estimates how many
people will ride alone in cars, carpool, take the bus
or other transit service before finally assigning all of
these trips in a four-hour morning, four-hour eve-
ning, and 16-hour off-peak period to a network that
represents streets in our region (and Morrisville).
The results were used to help our consultants think
about where to plan for future roadway improve-
ments.This is not a straightforward process, since
our modeling work suggests that adding more ca-
pacity to some of Morrisville’s streets – convenient
routes between the big employment generators to
the north and the big residential communities to
the south – simply adds more cars without reliev-
ing congestion. Not all streets in Morrisville are
included in theTRM, nor are the forecasts of land
uses to the year 2035 going to be without error.
Continuous re-examination of the model is the key
to keeping its results relevant. Morrisville partici-
pates in the modeling process by submitting their
best forecast of future land uses in the town.