Do Safer Roads and Vehicles Make For Safer Driving?

A new study showing that bad roads contributecalm traffic, traffic calming devices include speed
for more than half of the traffic fatalities in thebumps, roadway restrictions, and signs painted on
US has stirred a lot of debate. From 1979 to thethe road surface. Probably the best and most
present, most studies have shown that drivervisible examples of traffic calming procedures are
error is most responsible for traffic collisions. Arethe traffic circles that are replacing traditional
bad roads at fault and will improving the roadsfour-way intersections. Traffic circles allow traffic
reduce the fatality rate? There is some data toto move through an intersection without the use
show that the traditional methods of roadof traffic lights. Traffic circles force drivers to
improvement may actually make the roads moreslow down upon entering but keep traffic moving
dangerous.more smoothly due to the lack of traffic lights.
A lot of the nation's highways are in bad shape,Traffic calming measures have been implemented
including bridges and overpasses. There is nofrom Florida to Washington State but city
doubt that we need more and better roads toplanners are finding that they are very expensive
relieve the traffic burden; especially in large cities.to install and maintain. Traffic calming is most
However widening roads, adding more signs andoften seen on urban streets with lower speeds.
clearer lane markers may not be the bestStudies have found that implementing traffic
answer. There have been some argumentscalming measures on major highways have had
claiming that widening roads and painting clearerlittle impact on speed control.
markings will lead to the "Peltzman Effect".Hans Monderman, a Dutch traffic engineer looked
Sam Peltzman, a professor of Economics at theat some of the traffic calming procedures and felt
University of Chicago theorized that people tendthey were ineffective. Monderman rejected the
to respond to safety regulations or safetynotion that wider roads and more warning signs
technology by engaging in more dangerouscreated a safer environment. He was hired to
behavior. He felt that people adjust their behaviorlook at a street in the Dutch village of Oudehaske,
to a regulation in ways that counteract thewhere speeding drivers had struck and killed two
intended effect of the regulation. One study thatchildren. Instead of employing the typical traffic
found the Peltzman Effect to be true looked atcalming devices, Monderman removed the curbs,
increased safety technology in NASCAR racetook out the signs, and used paving bricks that
cars. The study revealed that safetyhad the effect of making the road seem
improvements in race cars have resulted in riskiernarrower. The effect was to create enough
driving behavior and an increase in the number ofuncertainty in the minds of drivers that traffic
collisions on the raceway.immediately slowed down and the average speed
The Insurance Institute for Highway Safetywas dramatically reduced. Without signs or lane
(IIHS), in looking at new technology to make carsmarkings, the effect changed driving behavior
safer, warned that systems designed to keep amaking drivers more accommodating and
car from automatically straying from the lane orcooperative.
from coming too close to a vehicle ahead areOn another project, he removed the traffic
great in theory but they feel it will give drivers asignals and signs and replaced a traditional
false sense of security leading them to take theirfour-way intersection with what he called a
eyes off the road more often or allowing them to"traffic square". The resulting increase in
become more distracted.cooperation between motorists, cyclists, and
The intended effect of building wider, clearerpedestrians led to a dramatic decrease in the
roads is to improve the flow of traffic and to cutcollision rate. He often demonstrated the
down on injuries and deaths due to collisions. Theeffectiveness of this new intersection by safely
Peltzman Effect however says that, as roads arewalking backwards down the street with his eyes
improved, drivers feel they can take greater risksclosed.
and the average speed on the roadway increases.Keeping the Peltzman Effect in mind may help
As a result, the intended effect of making thedrivers, city planners, and traffic engineers to
road safer is offset by riskier driving behavior andmore safely negotiate the current driving situation.
the rate of collisions is basically unchanged.Drivers who rely on vehicle safety technology and
As a reaction to this, traffic engineers in citiesroadway improvements to keep them safe could
around the world have moved to a Europeanbe forgetting that safety on the roadway is
innovation known as "Traffic Calming". To slow orultimately their own responsibility.