Responses to the Problem of Speeding in Residential Areas
Your analysis of your local problem should give you a better understandingof the factors contributing to it. Once you have analyzed your localproblem and established a baseline for measuring effectiveness, you shouldconsider possible responses to address the problem.
The following response strategies provide a foundation of ideas foraddressing your particular problem. These strategies are drawn from avariety of research studies and police reports. Several of these strategiesmay apply to your community's problem. It is critical that you tailorresponses to local circumstances, and that you can justify each responsebased on reliable analysis. In most cases, an effective strategy willinvolve implementing several different responses. Law enforcement responsesalone are seldom effective in reducing or solving the problem. Do notlimit yourself to considering what police can do: give careful considerationto who else in your community shares responsibility for the problem andcan help police better respond to it. Regardless of which responses youprefer, it is strongly recommended that you consult with affected citizensand transportation authorities before implementing the responses. Muchcommon wisdom about how to reduce speeds is wrong, but unless citizensare properly informed and consulted about what is and is not effectiveand acceptable, they will not likely support your actions.
Engineering Responses
- Using traffic calming. Traffic calming describesa wide range of road and environment design changes that either makeit more difficult for a vehicle to speed or make drivers believe theyshould slow down for safety. The measures are also intended to makeroads easier and safer for pedestrians and bicyclists to use. Trafficcalming measures are particularly effective at reducing speeds in residentialareas.14 Someof the more common traffic calming measures are:
- narrowing the road,
- putting bends and curves in the road,
- installing road humps,†
† Road (or speed) humpsare different from speed bumps. Speed humps are about12 feet wide and 2 to 3 inches high, and can be crossedsafely at 20 to 30 mph. Properly designed, they can accommodatelarge vehicles such as fire trucks. Speed bumps are shorterand narrower, and can be crossed safely only at lowerspeeds. They can damage large vehicles. They are moreappropriately installed in parking lots than on roads.
- adding chicanes (traffic deflections that narrow or redirectthe road),
- marking the road to create the illusion that it is narrowing,
- adding pedestrian crosswalks that are raised or made fromdistinctive materials,
- planting trees and other foliage along roadsides,
- building traffic circles† androundabouts,††
† The city of Seattlehas installed over 600 traffic circles, mainly in residentialneighborhoods where they are popular among residents.The circles have helped reduce traffic crashesand resulting injuries dramatically (National Highway Traffic Safety Administration 1999). See www.usroads.com/journals (TranSafety)for detailed descriptions of traffic circles.
Read a short article about traffic circles in Seattle.
†† It is essentialthat vehicles traveling in the roundabouts have the right-of-way,rather than those entering the roundabouts, for themto be effective in reducing crashes (National HighwayTraffic Safety Administration 1999).
- building traffic islands (for pedestrians crossing a wideroad),
- installing gateways to residential neighborhoods,
- permitting parking on both sides of residential streets,†††
††† The speedreductions achieved by permitting parking must be offsetagainst the increased risk to pedestrians who dart intothe road from between parked vehicles.
- timing traffic signals for vehicles traveling the desiredspeed,
- erecting mid-block barriers that create two cul-de-sacs,and
- adding mid-block build-outs (sidewalk area extensionsinto the road).
The U.S. Department of Transportation prepares traffic advisoryleaflets that provide illustrations and technical details aboutmany road design features.
The Dutch pioneered the redesign of residential areas in waysthat blend driving and nondriving activities. Roads are designedas extensions of the public space used for walking, ridingand playing rather than as separate avenues for vehicle travel.15 Inthe United States, Seattle; Portland and Eugene, Ore.; andWest Palm Beach and Sarasota, Fla., have used traffic calmingmeasures extensively.
Traffic calming measures can be expensive, however, so theircost-effectiveness must be determined over the long term. Trafficcalming measures work best if they are understood and acceptedby the public, take into account the special requirements ofemergency response vehicles, and are reinforced with adequatelevels of police enforcement.16 Properlydesigned, traffic calming measures can also reduce noise levelsby reducing vehicle acceleration. Without traffic calming measures,it is difficult for police to reduce average vehicle speedsbelow 25 mph.17
- Posting warning signs and signals. Painting speedlimits or "SLOW" on the road surface, in combination withposting roadside signs, can help reduce speeds.18 Transversepavement markings create the illusion of high speed, and when placedahead of traffic hazards, have been shown to cause drivers to slowdown.19 Strobelight signals, flashing signals and warning signs painted in eye-catchingfluorescent colors can improve drivers' awareness of special hazardsand reduced speed limits.20 Wherethere are many other signs and sights competing for drivers' attention,it is not easy to get drivers to notice speed warnings. Warning signsand signals are more effective if they convey the reason that driversshould slow down (e.g., curve ahead, school zone, road construction).21 Othersigns, such as those that warn of children in the area, are not knownto effectively reduce speeds.22
Education Responses
The goal of education responses is to make speeding socially unacceptable.But given the current acceptability of speeding, there is the potentialfor a negative backlash against anti speeding campaigns.23
- Conducting anti-speeding public awareness campaigns. Anti-speedingpublic awareness campaignhave been recommended, even though theireffects may not be immediate and substantial; they help change thesocial acceptability of speeding and alter drivers' beliefs that theyare better and safer than other drivers.24 Publicawareness campaigns need not be overtly accusatory, but should conveyfacts about the dangers and consequences of speeding so as to debunkcommon myths about speed and driving. Because many drivers say theyspeed merely to keep up with traffic, encouraging voluntary compliancewith speed limits can help slow down those drivers who consciouslyor subconsciously follow the lead of other drivers.
A twist on the conventional public awareness campaign that discourages speedingis a campaign that encourages obeying the speed limit. In some campaignsof this sort, police have achieved positive results by stopping drivers andthanking them for obeying the speed limit; in others, signs have been postedindicating the percentage of drivers obeying the speed limit.25
An interesting method for making the public aware of the hazards of speedingin school zones comes from Lithuania. There, drivers are required to keeptheir headlights on at all times during the first week school is in sessionas a reminder to one another to drive carefully where children are present.
Some public awareness campaigns are professionally developed, using television,radio and billboards. These campaigns typically convey official, government-sanctionedmessages about speeding risks. Anti-speeding campaigns developed at the grass-rootslevel are potentially even more effective than official campaigns. Usingsimple lawn signs, speed display boards, warning letters, or personal appealsto speeders who have been stopped, these campaigns can convey more heartfeltmessages to speeders about the risks they create.
- Informing complainants about actual speeds. Complainantsdo not always estimate vehicle speeds accurately. Vehicle speed almostalways seems faster to a stationary pedestrian than to a moving motorist.Where you suspect that complainants' concerns may be exaggerated, youmight have a police officer monitor speeds with complainants present.Some complainants may be surprised to learn that vehicles are in facttraveling the speed limit. This does not necessarily mean that speedsare appropriate for the conditions, but at a minimum it helps complainantsbetter understand what responses might be most appropriate to remedythe problem.
- Providing realistic driver training. Realisticdriver training similar to what police officers receive can help driversbetter appreciate the effects of speed on their ability to controla vehicle.26 Properrealistic training courses require skilled instructors, special safetyequipment and protected driving areas.
Enforcement Responses
- Enforcing speeding laws. Long-term changesin drivers' attitudes toward speeding depend on drivers' perceivedrisk of being stopped.27 However,a considerable investment of resources is required to significantlyincrease the risk of getting caught.28 Thepublic generally supports speed enforcement, especially in residentialareas and other areas where there are children.29 Speedenforcement works best if
- drivers believe it will occur;
- it has meaningful costs to offenders;
- police apply it generally, rather than at specific times andlocations; and
- drivers are not tipped off by cues as to when it is or is nothappening.30
With respect to the last condition above, you must balance makingthe public aware of the enforcement campaign against allowing driversto anticipate precisely where and when officers are conductingenforcement. For example, you might consider advertising on theradio that the police will be enforcing speeding laws on particularroads on particular days, but not give visual cues to drivers ofthe exact location of the speed detection devices and officers.This will enhance the deterrent effect for drivers listening tothe radio, without reducing the deterrent effect for those whoare not. The enforcement times and locations should be varied enoughso that drivers do not become confident that they can avoid detection.Advance publicity of enforcement campaigns also increases publicsupport for enforcement by establishing a sense of fairness todrivers. Explaining why police have targeted particular locationsfor enforcement (e.g., high rate of crashes or citizen complaints)also increases public support.† Enforcementshould be conducted both at problem locations and at randomly selectedlocations to maximize deterrence.†† Stationarymarked police vehicles are more effective than moving marked policevehicles in reducing speed.31
† The Silverthorne, Colo., PoliceDepartment surveyed the community to determine the thresholds atwhich the public believed the police should issue speeding citationsat specific locations. The police issued the survey results todrivers stopped for speeding, thereby enhancing police authorityto enforce speeding laws and minimizing citizen complaints aboutspeed enforcement.
†† An Australian study concludedthat posting police officers in marked police vehicles on randomlyselected stretches of road at random times generally is a cost-effectiveway to maximize deterrence and reduce traffic crashes (Leggett1997).
Police enforcement is expensive to maintain consistently, andit quickly loses its effect where the enforcement effort is notvisible to drivers.32 Intensivespeed enforcement also loses its effectiveness because of the typicalincentive system for traffic officers—they are rewarded forissuing citations rather than for maintaining reduced average speeds.Consequently, as soon as the enforcement effort has the positiveeffect of reducing speeds, there are fewer violations and trafficofficers move on to other locations, after which speeds quicklyresume their pre-enforcement levels.33
Enforcing speeding laws with speed cameras.Speedcameras, also referred to as photo radar, are cost-effective in reducingspeeds, crashes, injuries, and fatalities, particularly when detectedviolations are prosecuted.34 Speedcameras, used in conjunction with other responses, were determinedto have been effective in reducing the percentage of speeders, vehiclecrashes, injuries, and fatalities in Victoria, Australia.35 There,speed cameras were mounted either in unmarked police vehicles oron tripods along the roadside, without advance warnings to driversabout the cameras' location. The police could move the cameras aroundso drivers could not predict where they were placed. Most were placedalong roads with 60-kilometer-per-hour (37.2-mph) speed limits, andso the results from this test do not necessarily apply to residentialroads. However, there is little reason to assume cameras will notwork on such roads. Some drivers slow down when approaching speedcameras, but quickly speed up once they pass.36 Thiscan be countered by hiding the cameras better and otherwise preventingdrivers from knowing exactly where they are. In some jurisdictions,the relatively inexpensive protective boxes in which speed camerasare placed are mounted in many locations, leaving drivers uncertainas to which boxes actually contain cameras at any particular time.
The public has generally accepted the use of speed cameras, especiallyin high-risk zones, although there are some strong objections to the invasionof privacy and preferences for personal interactions with enforcers.37 Speedcameras were first authorized by law in the United Kingdom in 1991; theyare now used by all British police forces. Norway has used them effectivelysince 1988.38 Notall U.S. jurisdictions have specifically authorized speed cameras for prosecution,and some states and municipalities have specifically rejected proposalsfor their use. You should first gauge public support for speed camerasbefore formally attempting to use them. There are also a number of issuesregarding the fees charged by companies that install and operate speedcameras, and how the revenue generated from fines is to be used.The first generation of speed cameras required that the film be takenmanually from the cameras, to be processed. More advanced technologyallows for more efficient remote image processing.39
- Using speed display boards. Speed display boardsmeasure oncoming vehicles' speeds and prominently display the speedsto drivers. Speed display boards have been shown to reduce speeds andcrashes, and appear to be at least as effective as speed cameras inreducing speeds, and to do so more cost-effectively.40 Speeddisplay boards are particularly effective with drivers who are notpaying attention to their speed. They are more effective when supplementedwith police enforcement—in this combination, the effect can lastseveral weeks after they are removed. Unattended display boards, however,are vulnerable to vandalism.
- Arresting the worst offenders. As one method forchanging public attitudes toward speeding, some police agencies haveamended their arrest policies and placed serious offenders (those drivingmuch higher than the speed limit) in custody rather than merely releasingthem with a citation. The intent is to convey a strong message thatdriving well over the speed limit is a seriously dangerous offenseand not a harmless technical infraction.† Thisresponse may require special legislation and policies.
† The Glendale, Ariz., Police Department (1998) used this response as part of a comprehensivestrategy to reduce speeding. The police department's custodialarrest policy was specifically authorized under state law.
- Having citizen volunteers monitor speeding. Somepolice agencies have recruited and trained citizen volunteers to operatespeed detection devices in residential areas.41 Thevolunteers record the vehicle speeds and license plate numbers andturn them over to the police. Police then send official warning lettersto the registered vehicle owners. Other police agencies, such as theMadison, Wis., Police Department, have had citizens join police officerson traffic stops to explain the community's concerns about speedingto drivers.
Responses With Limited Effectiveness
- Reducing speed limits. Speed limitsalone have little effect on actual vehicle speeds. Reducing postedspeed limits will typically decrease actual average vehicle speedsby only one-fourth of the reduction.42 So,for example, reducing the posted speed limit from 30 to 25 mph willreduce actual average vehicle speeds by only a little more than 1 mph.When speed limits are set lower than what most drivers consider safe(typically, the 85th percentile), the net effect is to cause many driversto ignore those speed limits, as well as other posted speed limits;43 ifpolice enforcement of the reduced limits fails to establish a credibledeterrent, drivers may increasingly lose respect for all speed limits.In some jurisdictions, a posted speed limit lower than the 85th percentilespeed may constitute a legal defense to enforcement. Careful speedstudies should be conducted before speed limits are changed. Similarroads should have similar speed limits so drivers do not come to believethat speed limits are set arbitrarily. 44, †
† The Wisconsin TransportationInformation Center (1999 [
FullText]) published a guide for settingspeed limits on local roads. Although it specifically refersto Wisconsin, much of the information applies to any jurisdiction.Traffic and road engineers may inadvertently increase vehiclespeeds when they build extra safety margins into the road designand speed limit.45 Forexample, if they want vehicles to travel 25 mph along a particularroad, they might set the speed limit at 25 mph, but design theroad using accepted guidelines for 30-mph travel, thinking thiswill provide an extra safety margin. However, the accepted guidelinesalready have a safety margin factored into them, so the resultis a double safety margin that actually makes the road seem safefor travel at 35 to 40 mph. Because most drivers travel at whatthey perceive are safe speeds rather than the posted speed limit,they will end up driving 10 to 15 mph faster than the engineersoriginally intended. This unintended effect reflects an underlyingtension in road safety—a desire on the one hand to buildroads that encourage drivers to drive at slower, safer speeds,and a desire on the other hand to make roads safe enough fordrivers who choose to drive faster. Road and traffic engineershave often tried to resolve this tension by making roads wider,straighter and more obstruction-free. More recent trends havebeen in the opposite direction, to get drivers to slow down.
- Increasing fines and penalties. Higher fines andpenalties, beyond the threshold that offenders consider meaningful,do not continue to reduce speeds.46
- Erecting stop signs. Many aggrieved citizens believethat erecting stop signs along residential roads will force driversto slow down. They pressure elected officials and traffic engineersto erect new stop signs. However, the most common effect on actualdriving behavior is that drivers speed up mid-block to make up forlost time, thereby keeping average speeds high, increasing accelerationnoise and decreasing fuel efficiency.47
- Installing speed bumps or rumble strips. Speedbumps, as opposed to speed humps, do not effectively reduce speeds,and can be hazardous.48 Rumblestrips—intermittent series of bumps across the road—donot reduce speeds directly; they merely serve to warn drivers of ahazard ahead.49
- Reengineering vehicles. New vehicle technologyholds some potential to control speeding, but most features are notyet standard or widely accepted by the public.50 Speedlimiters prevent a vehicle from going faster than a set speed. Speedlimiters can be programmed to receive electronic signals from transmittersalong the road and adjust maximum speeds automatically. So-called smartcards can electronically record a vehicle's speed and report it automaticallyto enforcement authorities. Electronic speed indicators, reading electronicroadside signals, can warn drivers they are speeding, or speed indicatorsin the vehicle can electronically trigger roadside warning signals.