Why is the WALK light so short, and the flashing DON'T WALK
light so long?
The flashing DON'T WALK signal for pedestrians is similar to a yellow
light for vehicles. If a person has started to finish crossing a
street and the flashing light appears, they will have time to cross
the street. If the flashing DON'T WALK signal appears and a person has
not started to cross the street, they should wait for the next WALK.
At some intersections, the WALK signal will not appear unless the
pedestrian push button is pushed.
At some intersections, there is not a pedestrian push button because
the WALK signal will automatically appear with the associated vehicle
green light.
"Flashing Lights-Do they Really Slow Traffic?"
Flashing beacons (commonly called flashers or flashing lights) are
frequently requested in the belief that they will reduce vehicle
speeds. Unfortunately, this is not necessarily the case. The following
discussion of flashing beacons is offered in the interest of broader
public understanding of what flashers can do and what factors must be
considered before they should be installed.
Effective Usage of Flashers
A flasher is generally installed at an intersection or in conjunction
with a warning sign in advance of an area requiring greater than
normal care by the average driver. Flashing beacons serve a useful
purpose where the flashing yellow is used to alert drivers to unusual
conditions that are not readily apparent, such as: obstructions in the
roadway, uncommon roadway conditions, narrow bridges, or unusual
conditions hidden from the motorists’ view. One of the more common
locations where a flasher can be used effectively is at a signalized
intersection located just beyond a vertical or a horizontal curve,
when the intersection is hidden from the view of approaching
travelers.
For any flasher to be effective, it must command the respect of the
traveling public. In other words, immediately after seeing a flasher,
the driver must consistently see an unusual condition which is being
singled out for attention. Furthermore, the condition that the driver
sees must be viewed as serious enough to justify his having been
alerted.
Unjustified Flashers
When flashers are used improperly and installed at locations where
they are not warranted, they soon lose much of their effectiveness.
They simply cease to command the respect of the drivers.
What happens is that after continually being alerted to a condition
which seldom, if ever, appears to be truly unusual, drivers actually
stop "seeing" the flasher. When this happens, flashers which are truly
needed may well be disregarded by drivers who have become conditioned
to believe that flashers are just "window dressing. "Because of this
normal human reaction, even one improper usage greatly reduces the
effectiveness of essential flashers."
Symptoms versus Problems
Quite often, requests for flashers are emotional responses to
symptoms, rather than attempts to solve underlying problems.
To put this into perspective, let's use an appropriate analogy: the
case of measles. Obviously, to cure a patient who has measles, the
disease itself (measles) must be treated - not the symptom (rash). In
traffic control, it is not uncommon for public responses to be
directed at treating symptoms.
For example, in cases where concerned parents are requesting flashers
on pedestrian warning signs, a traffic investigation all too
frequently reveals that:
- There is no "safe route to school" plan for the school.
- There is no pedestrian safety program in the school.
- Very young children are allowed to travel to school by whatever route
they prefer.
- Parents are willing to abdicate their responsibilities by placing the
entire burden for pedestrian safety on a traffic control device.
Local law enforcement officials turn a blind eye to pedestrian traffic
violations.
- Where traffic laws are enforced by conscientious law enforcement
officials, parents claim that the fault lies in inadequate traffic
control devices, not in their children's actions.
Flashers that are installed when these unwarranted conditions exist
result in the following:
- The flasher soon becomes part of the normal driving environment and is
ignored.
- The community continues to avoid treating the real problem.
- Other flashers, which are justified, are frequently disregarded by
drivers conditioned to believe that flashers can be safely
disregarded.
In summary, when flashers are properly located, they serve a useful
function. When they are used improperly and installed in locations
where they are not warranted, they soon lose much, if not all, of
their effectiveness. More seriously, improper usage greatly reduces
the effectiveness of other flashers installed in areas where there is
a real need. Above all, it is essential to prove that there is a
problem which can be solved through the installation of a flasher
before actually employing one. Too often, flashers are installed when
someone assumes there is, or is going to be, a problem. It is of the
utmost importance that flasher installation beheld to a minimum in
order to maintain a high degree of respect for the flasher
installations that are truly needed.
What is Traffic Calming?
The term "Traffic Calming" is used to describe methods of altering the
behavior of traffic to suit the character of the area it moves
through. The most apt example of this character occurs where a local
street is used by motorists as a short cut from one arterial to
another. Because cut-through traffic often moves faster than
neighborhood traffic and there is a lot more of it, this use can
severely degrade the character of the street. Increased volume and
increased speed can lead to a more dangerous, less pleasant street and
discourages its use by bicyclists, pedestrians and children.
As concern over safety and the desire for improved pedestrian and
bicycle safety increases, communities across the country are looking
at installing traffic calming measures to improve safety and reduce
vehicle speed.
Traffic Calming is a form of traffic planning that seeks to equalize
the use of streets between automobiles, pedestrians, bicyclists, and
playing children. This is accomplished through the use of devices and
techniques that reduce traffic volume and speed in neighborhoods while
maintaining maximum mobility and access. Traffic calming also attempts
to make drivers aware of the fact that they are sharing the space of a
street with other users.
- Cynthia Holye, Traffic Calming, 1995.
Here in East Baton Rouge Parish, the need for traffic calming was
brought about by the increased requests by neighborhood groups to "do
something" about the quantity of traffic using their neighborhoods as
cut-through thoroughfares.
Other Benefits
The overriding purpose of traffic calming devices is to discourage
non-local traffic from cutting through neighborhoods. There are
several other benefits to the process as well. Because many traffic
calming strategies reduce vehicle speeds for all the traffic on the
street, safety on that street is increased. Because many traffic
calming strategies use landscaping and pavement treatments, these may
serve to enhance the aesthetic look of the neighborhood.
Need for Traffic Calming
The need for traffic calming stems from an increase in complaints
about traffic on neighborhood streets. Increased traffic through
neighborhoods threatens the integrity and character of the
neighborhood and puts non-motorized users at risk. Limited resources
of the City prevent comprehensive enforcement of speeds, volume, and
safety.
The increase in traffic through neighborhoods is likely caused by one
or more of the following:
- new development in neighborhood creating increased traffic,
- cut-through traffic avoiding congestion on arterial streets,
- re-routed neighborhood traffic due to obstacles at other outlets.
Traffic calming. What is it?
Traffic calming is an attempt to strike a balance between vehicular
traffic and everyone else who uses the street: pedestrians, bikers,
business people and residents.
That balance tilts away from cars. Some see traffic calming as a way
of "reclaiming" local streets from a traditional domination by
automobiles. Others see it more modestly as a way of trying to restore
the safety and peace in neighborhoods that are becoming overwhelmed
with speeding traffic.
In many ways, this approach upends the traditional goals of traffic
engineering, which strive to move auto traffic quickly and
efficiently. Roads have been designed as wide, straight routes, with
few obstructions to the motorist's vision or progress, and strict
barriers or space between vehicles and pedestrians.
Traffic calming, by contrast, seeks to do the opposite.
What is the point?
The goal is to slow vehicular traffic, and in some cases discourage
drivers from using certain roads.
How is that done?
By altering the design of the road, introducing obstacles, and
otherwise making the path a bit more difficult for vehicles, motorists
will be forced to drive more slowly and carefully. There are dozens of
techniques for this, ranging from narrowing the roadway, to creating
medians, to allowing on-street parking, to installing speed humps.
Does it work?
Yes. Before-and-after traffic studies in many municipalities show a
reduction of speed and a reduction in the traffic volume after calming
changes are made. Many proponents believe it also reduces accidents,
though that claim is less well documented.
Are there drawbacks?
Yes. Police, fire and ambulance response times will be slowed. Some
designs bring pedestrians, parked vehicles and bicyclists in closer
proximity to moving cars, which may increase safety risks. Slower
vehicle traffic could create traffic back-ups. Not all drivers will
navigate the obstacles designed to slow their speed. Roadway
alterations require construction costs.
Is it popular?
Citizen surveys in some municipalities show traffic calming to be the
most requested and most popular government program. Other city
councils have been stormed by irate residents demanding the removal of
speed bumps or traffic circles. The difference seems to lie in having
a clear and predetermined program, objective criteria for adopting
traffic calming, a variety of options, and extensive public
participation in the planning phase. There are dozens of variations of traffic calming techniques, limited
only by the imagination of architects, motivated residents and road
engineers. For a more thorough list and definitions, please see the
glossary. Here are some of the more common techniques, with tips on
their advantages and disadvantages.
Types of Traffic Calming Methods.
- Speed bumps, humps and tables.
All in the same family, they raise the pavement three to four inches.
Although the terms are popularly used interchangeably, engineers refer
to speed "bumps" as narrow and abrupt, best confined to parking lots.
Speed humps and speed tables are more gradual, often 22 feet
start-to-finish, usually with a flat top. They are comparatively
inexpensive. Effective in cutting down speed. Self-enforcing. Make
drivers think about their roadway. Also noisy, aggravating, and tough
on emergency vehicles.
- Traffic circles.
In residential areas, may be as small as 16 to 25 feet in diameter;
just enough to cause motorists to slow and alter their path. Rotaries
are larger versions used at major intersections. Both can be
attractively landscaped. Keeps traffic flowing. May confuse motorists
and make pedestrian crossing more difficult. Bicyclists sometimes find
them difficult to negotiate.
- Chicanes, bends or deviations.
Roadway redesigns that make motorists drive around fixed objects,
usually curbs extending alternately from opposite sides to form a
serpentine pathway. Visually pleasing, better for emergency vehicles.
Expensive.
- Neckdowns, chokers, bulbs.
Various forms of narrowing the road at midroad or intersections,
usually by protruding sidewalks into the street from one or more
sides. Can be aesthetically pleasing. Helps pedestrians cross. Can be
a problem for bicycles, snow removal.
- Narrow roads.
Using sidewalks, landscaping or striping to narrow lanes to about 10
feet. Drivers instinctively slow. Pedestrian-friendly, creates
neighborly scene. Can be tough on bicyclists. Eliminates on-street
parking.
- Raised intersections, changes in road texture.
Can use grooved asphalt, colored paving stones, brick, (or for the
ultimate effectiveness, cobblestones). Gets drivers' attention. Good
for pedestrians. Noisy for neighbors. Can be bumpy for bicyclists.
- Direction changes.
Accomplished by "diverters" that diagonally bisect an intersection,
traffic barriers that force cars to turn one direction, sidewalk
"bulbs" that block access to one lane. All force drivers out of
straight-line routes. Effective in stopping short-cut and cut-through
traffic. Can be costly, confusing to strangers and add to commutes and
emergency response times
Street Classification
The street network is constructed in a hierarchical manner to provide
efficient and effective routes from one’s origin to destination.
Arterial streets form the backbone of the street network. These
high-capacity roadways serve as direct links between different areas
of the city. Local collectors feed into these arterials allowing
motorists quick and easy access to the major roadways while at the
same time allowing pedestrians and bicyclists to move about their
neighborhood and to move from one to another. The majority of streets
in the city are local neighborhood streets. These streets provide
residents access to their houses.
Design Characteristics of Seven Roadway Classifications
|
|
Use |
Dimensions |
Volume |
| |
Trip
Length |
Design
Speed* |
Pavement
Width |
# of
Lanes |
Average
Daily Trips |
|
(miles) |
(mph) |
(feet) |
(#) |
(ADT) |
| Freeway |
> 5
miles |
70 mph |
72 –
96 |
6-8 |
80,000 |
| Expressway |
> 5
miles |
60 mph |
72 |
6 |
75,000 |
| Principal
Arterial |
1-2
miles |
45 mph |
83 –
120 |
6 |
15,000
– 50,000 |
| Minor
Arterial |
> 1
mile |
40 mph |
60 –
72 |
4-5 |
10,000
– 25,000 |
| Major
Collector |
1 mile |
35 mph |
44 |
2-4 |
3,500
– 10,000 |
| Minor
Collector |
1 mile |
30 mph |
36 |
2-3 |
1,500
– 3,500 |
| Local
Street |
< 1
mile |
25 mph |
34 |
2 |
200 –
1,500 |
* Design speed
refers to the design specifications and can differ from posted speed limit.
|