Traffic calming was introduced to the U.S. from Europe some 35 years ago, although the public still thinks of it as a relatively new concept. Over those years, many different neighborhood traffic-management techniques, including traffic calming, were tried in urban and suburban communities to help slow traffic speeds and make local streets safer. Many cities, towns and villages have formal neighborhood traffic-management programs with relatively similar criteria to apply for consideration of various techniques.
Do they work? Do residents like them? While there have been many success stories, there also are many locations where controversy continues over traffic calming. Statistics prove that there are positives and negatives to each technique, but in many instances perception seems to be the biggest factor in determining the success of a traffic-calming program.
Not a friend in the neighborhood
A review of available literature and websites confirms that the speed hump continues to be the most commonly implemented traffic-calming technique in the U.S. There are many studies that demonstrate benefits from speed humps that make them popular. Depending on the spacing of the humps, statistics show that significant speed reductions can be achieved. Although they are not necessarily designed to achieve it, speed humps also may significantly reduce traffic volumes, according to some studies. There have been studies that demonstrate that noise is not increased with the addition of speed humps, but safety is improved.
Speed humps are relatively cheap, which, along with these studies, make it appear that they are the “holy grail” of neighborhood traffic management. However, just as many studies indicate, they are detrimental to neighborhoods.
There are numerous cities and municipalities across the U.S. that prohibit the use of speed humps or at least discourage their use. Many quote statistics from test results around the world that indicate that speed humps do not significantly reduce vehicle speeds once the vehicles have left the hump; present a potential hazard to all vehicles and particularly to bicyclists, motorcyclists and emergency vehicles; cannot be designed to meet the specifications for all types of vehicles; often increase traffic volumes on streets adjacent to streets where humps are located; and increase noise levels when vehicles hit the pavement after going over a hump. In addition, some states do not recognize the speed hump as an official traffic-control device, which may result in additional liability.
In some locations, speed humps have actually been removed in response to complaints from residents and emergency-service providers about noise and increased response times. Delays to emergency-response vehicles due to speed humps have been documented, as well as injuries to firefighters who have hit the roofs of their cabs while traversing speed humps. Studies have shown that speed humps increase vehicle emissions. A community stopped installing speed humps because of complaints from the disabled community that speed humps violate the Americans with Disabilities Act due to pain and inconvenience of traversing them. Some communities do not install speed humps because they make snow and ice removal more difficult. There also are drainage issues at low points on either side of the humps, and children use the humps for skateboarding.
Like any traffic issue, there are two sides to the story. The question to ask all involved stakeholders before installing speed humps is, “Are the speed reduction and other benefits worth the potential drawbacks?” Residents along two parallel streets in the city of Rochester, N.Y., have varying opinions.
A Kodak moment
Winchester and Merrill streets are relatively short, parallel, east-west residential roads. They connect two heavily traveled north-south arterial roads. They bound the north side of Kodak Park, which is the primary manufacturing facility for the Eastman Kodak Co. One of Kodak Park’s main employee parking lots has an access point to Merrill Street. On the south side of Kodak Park, State Route 104 is a heavily traveled principal arterial road which can often experience delays. These two residential streets, as well as Eastman Avenue, provided a convenient cut-through between Lake Avenue and Dewey Avenue to avoid this congested area of Rte. 104.
In 1997, Kodak decided to consolidate parking lots for better security and to remove hazardous waste transport from public streets. To make this happen, Eastman Avenue was closed to become part of the Kodak parking lots or internal road network. With the closure of Eastman Avenue, Winchester and Merrill were the only two connections between the north-south arterial roads for over 21?2 miles north from Rte. 104. This made cut-through traffic an even greater problem along these residential streets.
A study was conducted to assess the potential traffic effects of closing these streets to public traffic and to determine appropriate neighborhood traffic-management measures. Data was collected and forecasts were made concerning traffic diversions. Community workshops were held with the neighborhood association and the city of Rochester to discuss concerns and work with residents to develop an acceptable neighborhood traffic-management plan. One key mitigation measure agreed to was the installation of speed humps on Merrill Street and Winchester Street to slow traffic down and to entice motorists to use Rte. 104. The road closure and speed humps were implemented in 2000.
Speed-hump happiness?
In 2001, a follow-up study was prepared to see if the speed humps were effective in controlling the speed and amount of cut-through traffic using Winchester and Merrill streets. Peak-hour traffic counts revealed that traffic on Winchester Street decreased by 15-21%, while traffic on Merrill Street decreased by 23-27%. Traffic was using Rte. 104, as hoped, and speeds were reduced by 20-35%.
John Thomas, transportation specialist with the city of Rochester, coordinates the Safe Passages Neighborhood Traffic Program. Thomas felt that “the project went very well” and that the speed humps were “extremely effective” in reducing speeds. The toughest part was that speed humps were needed on both of the parallel streets, because putting speed humps on only one would cause traffic to divert to the other. Getting the required 75% petition rate was the most difficult aspect, as residents on Winchester Street were generally in favor, while Merrill Street residents had more concerns. A significant percentage of houses on Merrill Street are actually owned by Kodak and rented out. Many of these residents did not want the inconvenience of the speed humps. Kodak was in support of the speed humps.
Thomas also conveyed the disparate opinions within the city emergency-service providers. The Rochester Police Department wanted the speed humps higher to further reduce speeds, while the Rochester City Fire Department thought there were too many streets with speed humps around the city and had concerns with increased response times. It should be noted that the fire department has veto power over all speed-hump installations in the city.
Perhaps the most important views on the speed humps are from the residents who live on the two streets. A survey was mailed to the 176 houses and asked residents to rate how effective they felt the speed humps were in reducing speed and traffic volumes. They also were asked about what they felt were the positive and negative aspects of the speed humps.
The survey results clearly revealed the role of perception in the evaluation of traffic calming. While many residents rated the speed humps as highly effective in reducing speed, just as many felt they had no effect at all. Since the speed data shows that a significant reduction in speed has been achieved, some drawbacks or negative perceptions of speed humps appear to be influencing the feelings of some residents.
An interesting aspect of the survey was the difference in results from the two streets. While the city had much more difficulty in finding the minimum 75% of residents who wanted the speed humps on Merrill Street, residents of that street felt more positive about the speed humps than residents on Winchester Street.
The open-ended questions yielded responses just as diverse. When comparing positive and negative aspects of the speed humps, the survey showed several people with positive and several with negative opinions on the same issues.
The final question asked was, “Are the speed humps good or bad for your street?” This yes/no question was stated to be purposely vague to try to gauge the overall attitude toward the speed humps. Interesting enough, while the average score on speed reduction was right down the middle, two-thirds of the respondents stated they felt the speed humps were good.
The Merrill Street/Winchester Street speed humps, like traffic calming in many other municipalities, have seen their “ups and downs” over their history from initial planning through years of service. The project’s speed-reduction statistics are consistent with data from other traffic-calming projects, indicating that speeds are significantly lower with the speed humps. However, it also is clear that the perceptions of the people who live on the streets vary greatly, from total acceptance to complete rejection. It is obvious that for some people speed reduction is not as important as personal inconvenience. Will the speed humps remain? The jury is still out. TME
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