Street Wise: Taking Rush Out Of Traffic

Traffic-Calming Measures Around Hartford Have Cut Accidents, Speeds

May 8, 2005
By TONI GOLD

I ran into one of my favorite neighbors recently, and asked him what he thought of the traffic-calming measures that have begun to appear on Hartford streets - and specifically the most obvious one in our neighborhood, the newly painted stripes on Whitney and South Whitney Street.

The stripes delineate sections of the street into alternating one-side-of-the-street parking areas, a treatment known as "parking chicanes." It has the effect of creating a winding, or weaving, driving lane, which is also narrower, where once there had been a wide, straight shot, with parking all on the same side, or no parking at all, from one intersection to the next.

Knowing my enthusiasm for traffic calming, the neighbor chose his words carefully: "Well, it does slow the traffic. And it sure makes you pay attention." Exactly.

Unknowingly, he had hit on the basic behavioral premise and the underlying genius of traffic calming: It makes you pay attention. David Engwicht, an Australian who was one of the earliest proponents of the art of traffic calming, argues that controlling a driver's natural propensity for speed is futile. A more effective approach is to engage the driver by emphasizing "uncertainty and intrigue" in the street environment - for example with parking chicanes, as on Whitney/South Whitney Street, or by raised and planted medians, as West Hartford has done on Asylum and Farmington Avenues.

Having to actually pay attention is a challenge for many American drivers. They assume that on the street, autos have priority, and aren't these created obstacles making it less safe? Well, no, as it turns out.

Many studies, such as the exhaustive 1999 "Traffic Calming, State of the Practice" by Reid Ewing for the Institute of Traffic Engineers, show that thoughtful traffic calming can have a dramatic effect on speed and safety, which are closely related. These studies have looked at the costs of traffic calming - such as increased trip length, emergency vehicle delay and traffic spillover onto other streets. But they have also have looked at the benefits of traffic calming, which range from the obvious ones of slowing speeders and reducing crashes, (especially fatalities), to increases in property values, more walking and cycling, noise and pollution reduction, and increased neighborhood interaction that helps reduce crime.

An evaluation model for traffic calming proposed by one transportation think tank suggests how to measure these repercussions, and further proposes how to calculate the financial value of each factor. Traffic calming comes out as a net benefit in most cases. This kind of sophisticated research is not done much by most local governments, but West Hartford and Hartford have both done some informal measuring of their own. Dave Kraus, the town engineer of West Hartford, said he's been told that citizens like the widened sidewalks and reduced speeds.

"Drivers can have too much flexibility," he said, adding that traffic calming is inexpensive. He reports reduced crash rates at Farmington and Mountain Road, where left-turn lanes have been added. Next year, West Hartford will continue building medians, eliminating lanes and widening sidewalks on Farmington Avenue, this time east of the town center. The town will also begin to experiment with bump-outs - curb extensions at corners, which narrow the pedestrian crossing distance - on Boulevard between Farmington and LeMay streets. Kraus says the town has no overall traffic-calming plan, but it does have an aggressive street reconstruction program, which allows it to look at each street as its turn comes up.

Hartford, following a citywide plan developed with the neighborhoods last year, has also begun to implement traffic calming on many of the city's arteries, mostly in the form of re-striping lanes to narrow them, often accompanied by added parking and bike lanes. The city is also experimenting with a "mini-circle" at Coventry and Cornwall streets, after one such experiment at North Beacon and Fern streets got a thumbs-down from the neighbors.

After seeing the parking chicanes on South Whitney Street, the residents of Charter Oak Place, a short residential street, asked for the same treatment to slow speeders, and have been pleased with the results. The residents and businesses on Franklin Avenue also asked for road striping after seeing what was done on Maple and Wethersfield avenues.

Hartford's "road diet," or narrowing of the streets, has had positive results, said city public works director Bhupen Patel. His department has documented fewer crashes and less speeding as well as smoother traffic flow and general public satisfaction. For example, speeds dropped overall an average of 6 mph overall on streets that have been "calmed."

But it is the crash data, or rate of traffic accidents, that are most interesting. The largest impact occurred on Capitol Avenue - a 60 percent reduction in accidents per month, according to numbers from two years before traffic-calming steps were taken and 13 months afterward.

On this wide street, parking lanes on both sides were delineated by striping, and bike lanes were added as well. The remaining two auto lanes, one in each direction, moved smoothly - but more slowly - confirming the research finding that traffic flow optimizes at 25-30 mph. Similarly, Main Street experienced a 38 percent reduction in crashes, Tower Avenue a 35 percent reduction, and Whitney/South Whitney a 25 percent reduction. Only Maple Avenue experienced no reduction in crashes or speed. Apparently Maple Avenue needs a closer look; it is probably a candidate for a different traffic-calming treatment.

Patel reports that state Sen. Billy Ciotto D-Wethersfield, co-chairman of the General Assembly's Transportation Committee, initially complained about Franklin Avenue, but after driving it a few more times, he reported being impressed at the more orderly driving behavior. However, Patel warns not to assume that Hartford's dramatic improvements could be attained in a suburban town: "We were starting from a higher level of chaos," he said. "There was lots of room for improvement."

One interesting change has been the elimination of reversible one-way traffic on Asylum Avenue at rush hours, a longtime practice much detested by neighborhood residents who found reaching nearby destinations difficult if not impossible at those times. Since the resumption of two-way traffic at all times, there have been minimal backups except at one bottleneck, where parking will be eliminated. How could this be, when nothing else has changed?

Walter Kulash, a consulting traffic engineer and the dean of new urbanist street designers, says when planners widen roads to meet projections for more traffic, they get more traffic. This is known as "induced traffic." By the same token, when road capacity is reduced, traffic volume is reduced. Where does it go? Kulash asks.

"Nobody knows," he says, answering his own question with a twinkle in his eye. And then he explains: "Traffic is not like sewage disposal, or educational services for schoolchildren - you don't have to accommodate everyone."

Toni A. Gold of Hartford is a Senior Associate with the Project for Public Spaces and a member of the Place board of contributors.