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Kansas State Firefighters Association

- Dedicated to the Safety and Education of the Kansas Firefighters -

Roundabouts stymie fire trucks

By Kevin Bates
Saturday, April 14, 2001 - Lawrence Journal World

When emergency crews rushed to get to the scene of a car-bicycle accident in western Lawrence earlier this month, they took different routes.

Lawrence Police cars took a route that included jogging through a traffic roundabout on Monterey Way.

The fire truck that left the station at 3708 W. Sixth St., though, went out to Wakarusa Drive, then south, then back east on Harvard Road, effectively avoiding the roundabout.

And while fire officials say the roundabout wasn't the reason for the difference in routes, they and city leaders are working to keep Lawrence's traffic circles from becoming traffic jams.

Jim McSwain, fire chief for Lawrence-Douglas County Fire & Medical, said his agency plans to present traffic engineers a report on where roundabouts and traffic circles would cause problems for large fire engines heading to emergencies.

"It's not like driving straight, and it does present some challenges," he said.

"We've obviously had some concerns, but all we're asking for is thought about where they're put. We want to have maximum efficiency in responding to emergencies."

Because fire engines are large and at times unwieldy, they can have trouble negotiating Lawrence's three traffic circles — located at Harvard Road and Monterey Way, 18th and Sweet Water streets and Eighth and Michigan streets.

George Williams, Lawrence Public Works director, said the circular intersections have been placed to avoid any traffic headaches.

"I think we've come to terms with being careful to not put them on major routes," he said. "There can be problems, but they've provided us with their routes for response, and we think we can work out those problems."

McSwain said the biggest problem is when a ladder truck is forced to negotiate a traffic circle. Because those trucks' turning radiuses are wide, drivers must take the left side of the circle and drive against traffic to make a 90-degree turn.

"We want them big enough to get through with relative ease," he said. "We don't like to have to go against traffic, but that one (Harvard Road and Monterey Way) has a relatively low amount of traffic and good visibility, so that's OK if we can get through with minimal hazard."

At least three other traffic circles are being planned: at 24th Street and Inverness Drive; Sunflower and Inverness drives; and 27th Terrace and Louisiana Street.

McSwain said he knew both sides would be required to compromise on the designs.

"We understand this is for the whole community," he said. "We're recommending a middle ground."



Problems Associated with Traffic Calming Devices

 by Kathleen Calongne

The report is a 400 page compilation of data and articles from the United States and abroad. Ms. Calongne offers the report to all interested individuals at her cost.

The following is the "Conclusion" of the report:


EMERGENCY RESPONSE ROUTES

The U.S. Department of Transportation (USDOT), the Federal Highway Administration (FHWA) and the Institute of Transportation Engineers (ITE) are encouraging the installation of traffic calming devices in our communities. Overlooked is the fact that cities building devices such as speed humps and traffic circles consistently violate ITE guidelines for their use. Devices are being placed on streets of all volumes and grades, regardless of their designation as critical emergency response routes.

The USDOT has stated recommendations for the design and use of devices that are approved "traffic control devices" in the Manual on Uniform Traffic Control Devices (MUTCD). The designation of calming devices as "geometric design features of the roadway" has allowed devices built on city streets to fall under the jurisdiction of city councils.

The political nature of calming projects has resulted in an attempt to ignore the concerns of our fire chiefs about delays the devices impose upon emergency rescue vehicles. Fire chiefs, as city employees, often will not voice concern until the level of risk becomes intolerable. An analysis performed by Ronald Bowman, a scientist in Boulder, Colorado http://members.aol.com/raybowman/risk97/eval1.html

and applied to the City of Austin, Texas by Assistant Fire Chief Les Bunte http://home.cfl.rr.com/gidusko/texts/tfc_calm.pdf proves we are in far greater risk from even minor delays to emergency response caused by calming devices than from vehicles – speeding or not.

In 1998 the ITE on behalf of the FHWA prepared an informational report on traffic calming in the United States and Canada. Reid Ewing, Associate Professor of Environmental and Urban Systems at the University of Florida and Chairman of the Surface Transportation Policy Project (STPP) in Washington at the time, authored the report. Mr. Ewing seems to reveal his bias in the chapter of his draft report, Traffic Calming: State-of the-Art, on emergency response. Ewing titles Chapter 7, "Agency Concerns (and How They Can be Addressed)." He characterizes the concerns of fire chiefs as "making points" (p. 150). He suggests that transportation planners use "strategies", including the "threat of liability", to make a "case" before city councils (p.162). He proposes that decisions concerning safety are better made by residents than the trained safety professionals of our emergency rescue services.

"Probably the most appropriate role for emergency services is ‘advisory’, as in Austin (Texas). After all, traffic and emergency services are independent line agencies that answer to chief executives and legislative bodies. One should not answer to the other." (P. 137).

". . . it is evident that emergency response routes should be negotiated rather than accepted unilaterally from the fire department.. . . .not only should response routes be negotiated, but they should be negotiated with ample public input. Residents are the best judges of risks to themselves from traffic, fire and emergency medical incidents". (p. 155)

Mr. Ewing contends emergency calls are "rare" compared to the "constant problems of speeding traffic." (p.162) He, as many transportation planners, compares emergency calls to speeding cars, equating every car traveling as little as one mile per hour over the speed limit to a call from a resident stricken by a medical emergency or a structure on fire.

Emergency calls are not the rare events Ewing and some members of city councils and transportation divisions would like to believe. The City of Houston, for example, responds to an average of 150,000 emergency medical calls and 100,000 fire calls per year. While calming devices are purported to increase safety, Reid Ewing’s final report (1999) acknowledges assessment of the safety benefits of calming devices is inconsistent.

Ewing states:

" Traffic calming in the U.S. is largely restricted to low volume residential streets. Collisions occur infrequently on such streets to begin with, and any systematic change in collision rates tends to get lost in the random variation from year to year.

This limits our confidence in drawing inferences about safety impacts of traffic calming. (Traffic Calming: State of the Practice p. 123)

Confronted with evidence that collisions and vehicle/pedestrian conflicts are infrequent on neighborhood streets, transportation planners turn to livability as justification for devices. Residents, however, are fervently divided in their opinions about the benefits of the devices and their purported impact on quality-of-life. Many residents object to the increased noise, pollution, vibration, signage, discomfort in negotiating the devices on a daily basis to reach their homes, as well as to their impact on residents with disabilities and the threat to the well-being of their family members from delayed emergency response.


 CALMING POLITICTS VS. SAFETY AND COMMON SENSE

Calming projects have proceeded in the United States largely because they are biased toward those who want the devices, eliminating the voices of those downstream from the devices and those on parallel streets where traffic will be diverted.

City councils are funneling millions of tax-payer dollars into the devices without knowing whether slowing vehicles to speeds below posted speed limits, required to negotiate the devices, results in fewer vehicle/vehicle or vehicle/pedestrian conflicts. When post-studies at devices show a dramatic increase in accidents or pedestrian/vehicle conflict, devices are rarely removed. Pre-installation speed tests are sometimes conducted repeatedly until the desired results of speeding are attained. Political support for devices in the United States, predicated on the numbers of devices in other countries, ignores all negative data from other countries indicating resident opposition and problems from their long-term use.

The allocation of jurisdiction over the installation of calming devices to city councils and employees of Public Works Departments has culminated in an unprecedented compromise of community safety. People around the country are calling for an end to the installation of all deflection devices that impede emergency services, harm residents with disabilities, damage vehicles and increase pollution and disharmony in our communities. A truly independent and scientific cost/benefit analysis of the data available on the issue from this country and abroad should be conducted by an agency of the U.S. government to determine which, if any, devices can be safely used in our communities and what standards for the design and placement of the devices must be required of our local governments.

A cost/benefit analysis should include an assessment of the following:

· Risk to resident lives from delays to emergency response, using the analysis developed by scientist, Ronald Bowman of Boulder, Colorado

· Effect on driver, motorcyclist, bicyclist and pedestrian safety

· Potential effects on patients with varying medical conditions transported to local hospitals by emergency vehicles

· Effect on disabled drivers

· Damage to emergency vehicles and commercial vehicles as well as damage to sensitive equipment transported by such vehicles

· Increased auto emissions and fuel consumption from repeated deceleration and acceleration to negotiate devices

· Increased noise on residential streets

· Decreased property values on residential blocks where speed humps installed

· Potential legal liability to cities for injuries caused by foreseeable hazards related to placement of obstructions on public streets

· Impact of conflict over desirability of devices on the harmony of American neighborhoods

The proliferation of traffic calming devices in communities across the United States should be of immediate concern to our federal government. Lacking investigation, the political agendas of individuals in our local and federal governments will continue to suppress all meaningful consideration of the impact of traffic calming projects on the safety and well being of our communities.

Kathleen Calongne

CalongneK@aol.com



The following position statement was approved at the July, 2002 meeting of the Santa Barbara County Taxpayer Association meeting. Questions or comments should be directed to Mr. Joe Armendariz, Director. The Chair of the Transportation Committee is Scott Wenz.

TRAFFIC MANAGEMENT & ROUNDABOUTS

 

------ Cover page

TRANSPORTATION COMMITTEE REPORT

FOR

THE SANTA BARBARA COUNTY TAXPAYERS ASSOCIATION

_ _ _ _

TRAFFIC MANAGEMENT & ROUNDABOUTS

SUBMITTED AT THE JUNE 2002 MEETING

Approved and adopted at the July 2002 meeting

-------- Body

Introduction

A significant portion of the "Alternative Transportation" discussion in Santa Barbara County is the management of intersections. One of the most persistent designs put forth by anti-car groups is the Roundabout. When confronted with the charge that this is a "traffic calming" device intended to cause congestion and inhibit the smooth flow of traffic they have consistently denied this. Yet the Federal Department of Transportation is circulating an independent publication called, Designing Sidewalks and Trails for Access3 where the roundabouts are listed under "traffic calming" devices.2 This publication quotes The Institute of Transportation Engineers as stating that traffic calming is "...the combination of mainly physical measures that reduce the negative effects of motor vehicle use, alter driver behavior, and improve conditions for nonmotorized street users, 1999."

Examples of roundabouts often promoted are those primarily in Europe and England. The chief argument for roundabouts is that they provide a continuous feeding of traffic through an intersection without the need for stopping. The theory then states that as a result of this continuous movement of traffic there is reduced travel time, reduced pollution, and reduced accidents (and severity of accidents). Most often the primary argument "for" is based solely on perceived time delays. The most significant analysis of intersection design currently used is based upon delay. This is qualified in a system based upon the so called Level Of Service (LOS). The grading of each intersection, "A" through "F" is based on the ability to process traffic with or without significant delay.

The argument against roundabouts include the lack of pedestrian safety, lack of bicycle safety, placement requires more land area then conventional intersections, a greater cost of construction, the need to remove parking adjacent to roundabouts, and the fact that as an un-regulated intersection accident responsibility is difficult to assign. This difficulty exists because vehicles are not required to stop. Right of way determination is at best difficult to determine. Accident rates often increase after installation of a roundabout.

Location Examples

Massachusetts

In the United States, Massachusetts stands out as having the greatest number, and the longest history of roundabout application. The traffic review group Cars Are BasicTM contacted the head of traffic management for the state of Massachusetts (1998) and asked him as to his experience and opinion of roundabouts. He pointed out that his state was in the process of removing small and medium roundabouts (rotaries) because of the problems of congestion that they cause. He stated that when volumes of traffic reached rush hour peaks, and with the added problem of pedestrian management, they are not desirable. The direct quote is, "roundabouts are contraindicated where pedestrians are present." He did state that he supported roundabouts on large highway and freeway interchanges as long as they are designed in accordance with specific safety standards and include properly designed entry point deflections. The proper entry angle is dependent on having ample land available with adequate site lines on each approach, and a large turn radii. He supports the concept and use of roundabouts in proper context. This is the difference between the old concept of traffic circles or "rotaries" and the modern day roundabout.

Utah

Park City Utah is another location that has been held up as a great example of roundabout installation. Talking with both commuter workers and residents of Park City the apparent reality is that the construction has created more problems then it solved. The problems are associated with peak traffic congestion (roundabouts are supposed to solve this), and the creation of an un-regulated intersection. All of these problems are the issues that have plagued the City of Santa Barbara.

Santa Barbara

There has been a consistent public relations campaign supported by those interested in making car travel a thing of the past. The Santa Barbara News-Press last year printed an article praising roundabouts with a picture of the Milpas/Carpinteria Street roundabout at a low traffic period. This story was a syndicated publication that based its information on a report published in the American Journal of Public Health, April 2001, Vol. 91, No. 4. Reading the abstract one would believe that roundabouts are akin to the second coming of the savior of the world. A critical review of this is attached at the end of this paper. This paper pointed out that the "expected" number of accidents at this intersection without conversion to a roundabout equaled the actual accidents after conversion to a roundabout.2

The short of it is that the methodology of the paper is flawed, yet to their credit the authors point out that the type of small and medium roundabouts of the type planned in this county are on streets that should not have them. These are streets that are business oriented, tend to have pedestrian traffic, have periods of high traffic flow as diversion routes, and/or have substantial bicycle traffic.

Salinas/APS - Milpas/Carpinteria

A quick look at the reality of both the Salinas St./APS/Sycamore Canyon roundabout (rush hour and diversion route), and the Milpas St./Carpinteria St. roundabout (business & rush hour) proves the wisdom of the Chief Traffic Engineer of the State of Massachusetts. When the City of Santa Barbara traffic engineer, George Gerth claimed "success" of the roundabout at the Salinas intersection as an example of why the Milpas roundabout would work it would appear that he did not look at the results of the predicted theory of recognized roundabout experts. This same traffic manager has declared the Milpas St. roundabout a success despite official City of Santa Barbara accident figures to the contrary (300% increase in traffic accidents, 2 deaths, and congestion at rush hour at Milpas/Carpinteria Streets.)4. It is note worthy here to mention that approximately 1/3 of the increase in accidents reported are due to intoxication. Which means that those with impairment have difficulty negotiating this type of intersection. There is anecdotal evidence from witnesses and debris that more than the reported accidents have occurred. The current protocol for investigating automobile collisions is that no reports are made unless there are injuries or at least one vehicle was damaged so badly it was un-driveable and had to be towed from the scene. Additionally the following effects occurred: it was 100% over budget (2.5 vs. 5.1 million dollars), several months over due on completion, dramatically hurt nearby local businesses, and has yet to have built the required pedestrian bypass that will cost millions of dollars more.

An "Unintended Result" of the Milpas/Carpinteria roundabout is the fact that the amount of traffic Eastbound on Carpinteria St. exceeded design year (2015) projections within a year of the installation. Vehicles are not required to stop, entrance to the street from the roundabout is at an accelerated rate, and it encourages north bound drivers to turn eastbound on Carpinteria without slowing. The change to a roundabout eliminated the safety factor of a regulated intersection. The accident and death rate further down the block on this street sky rocketed after the roundabout was built and residents demanded the city do something about the speed and traffic volume on the street. All this as a direct result of a design that was intended to make traffic safer.

Goleta

Six roundabouts have been proposed for the new City of Goleta. These proposals are in part based upon glowing reports of the "success" of the Salinas and Milpas street roundabouts by obviously biased proponents. In addition to the dangers inherent in a roundabout sited at an inappropriate location similar to the Milpas St. roundabout is the increased expense verses a standard intersection, and larger land area needed for building such a device. This is further supported by the example of the Salinas/APS rotary.

Just the "improvements" after construction like the circular medium cost an additional $250,000.00, for an area approximately 20 ft. across and has not provided any remedy for pedestrians. Recently the city tore out this and planted a tree in the middle of this circle despite the fact that it was designed to be driven over in case of emergency. How the City of Goleta will handle such pressures will be instructive.

North County

It would appear that North County (Lompoc, Santa Maria, Guadalupe) is under these same pressures to "calm" traffic. Yet these are locations that are growing and developing traffic counts and increased populations that the above examples dictate should not have roundabouts. The only instances that would appear to benefit by the construction would be some of the intersecting highways and freeways. There is land space available to build the multi-acre roundabouts that work efficiently, do not have the inherent problems of pedestrian traffic, tight radii, insufficient lanes, and business traffic. A concern that this report has is the City of Santa Maria that constructed a roundabout at a growth area. This has the potential of becoming the same type of congestion and accident problems that have been reported above.

Impacts on pedestrian access

Under signals Building a True Community (final report) has developed among its guidelines for for roundabouts the recommendation that "(C) Signals. A pedestrian acutated traffic signal complying with x02.5.2 shall be provided for each segment of the crosswalk, including at the splitter island. Signals shall clearly identify which crosswalk segment the signal serves."1 This completely negates the concept of free flow of traffic that the proponents of roundabouts have tauted to be a primary reason for building roundabouts. The discussion section of this chapter is quite detailed but it is instructive to quote the following: "While this traffic pattern has been an asset to traffic planners in controlling and slowing the flow of traffic at intersections in lieu of having a signalized intersection, the absence of stopped traffic presents a major problem for blind and isually impaired pedestrians when crossing. .... Pedestrians report that vehicles at roundabouts, right slip lanes, and other unsignalized pedestrian crosswalks often do not yield for pedestrians."1 What this states is that most certainly roundabouts are not pedestrain friendly and they are most definitely considered traffic calming devices despite the ascertations of the city of Santa Barbara to the contrary.

The following are quotations from Desiging Sidewalks and Trails for Access.3

Negative impacts:

Motorists exiting the roundabout are often not required to yield to pedestrians..;

If properly designed, the crosswalk locations are set back from the intersection,.... Setback crosswalks are difficult for people with vision imparments to identify becasue they are not at the roundabout itself. (note this takes additional space that detracts from parking capability of the street);

Busy roundabouts provide very few gaps long enough to cross. This can be especially problematic and unsafe for pedestrians such as children, elderly with mobility and cognitive ivsion impairments;

Pedestrians with vision impairments experience difficulty seizing the right-of-way from exiting drivers due to the lack of pedestrian to driver eye contact;

Due to the wide turning radii at the corner, pedestrians with vision impairments may fail to identify the intersection; (note this includes intoxicated walkers)

Roundabouts are confusing for people with cognitive impairments due to the irregular design of the intersection....; and

When a crosswalk is setback from the intersection, pedestrians have to walk longer distances out of their way to cross the street. Some pedestrians will use the most direct route regardless of the crosswalk. (note this phenomina has been observed by members of this committee at the Milpas/Carpinteria roundabout from the first day of operation)

Add these negative observations to problems listed above and the grave concerns about emergency evacutation then the problems become daunting. The admonition to not build roundabouts (rotaries) where there is heavy peak traffic conditions, constantly heavy traffic conditions, commercial traffic conditions, or concerns about bike and pedestrian takes on important and serious weight in this light.

Final note

It appears that a common tactic by those in favor of roundabouts is to dismiss the expense and other objectionable factors related to them. They then pick an intersection that is in need of long over due maintenance, and possibly has other factors contributing to hazardous traffic operation such as improper signalization. Multiple options are then presented all of which include a variation of what they want and leave out other reasonable alternatives. This was very apparent with the City of Santa Barbara decision to build the Milpas/Carpinteria Roundabout.

Conclusion

With the increased population density witnessed in the entire County of Santa Barbara, and the concurrent increases in cars and trucks on the roads it is obvious that roundabouts or "rotaries"are not desirable intersection design for intra-city urban locations. Vehicle safety, evacuation route concerns, cost, increased size of intersections, loss of parking, creation of un-regulated intersections, and the need for safe bicycle/pedestrian alternatives that roundabouts adversely impact are all points against their construction.

Roundabouts are reasonable alternatives for highway and freeway junctions. Where there is enough room to create the proper deflection angles, maintain vehicle speed, and have safe travel because of the available land for proper planning they make sense.

Bibliography

1. Building a True Community

Final Report - Public Rights-of-Way Access Advisory Committe

U.S. Architectural & Transportation Barriers Compliance Board

January 10, 2001

----

2. Crash and Injury Reduction Following Installation of Roundabouts in the United States.

R.A. Rerring, B. N. Persaud, P. E. Garder, and D. Lord

American Journal of Public Health

April 2001, Vol 91, No. 4

----

3. Designing Sidewalks and Trails for Access

Best Practices Design Guide

U.S. Department of Transportation

Federal Highway Administration

September 2001

----

4. Milpas Roundabout Traffic Study

Presented July, 2 2001

Willdan Associates

City of Santa Barbara, California

--------

REVIEW OF AMERICAN JOURNAL OF PUBLIC HEALTH

Bibliography item #2The following review of this article was prepared by a former City of Santa Barbara police officer who worked as a traffic accident investigator and is presently working locally as an attorney.

A. Methodology

1. The method of extrapolation using a small sample is bad science. The projections of how many accidents the researchers predicted "would have occurred" if the roundabouts were not installed is not supported by an empirical evidence.

2. Only 4 intersections involving signal lights were studied before and after the conversion to roundabout.

3.. Any bona fide reduction in accidents or more accurately injury accidents are a result of the forced reduction in speed not the roundabout per se. The theory states that the angle of deflection is such as to force a speed reduction lessening the severity of impacts.

a. No significant information is provided as to whether the signalized or previously un-controlled or partially controlled intersections had speed limits of 35-55 mph. Obviously a reduction of such speed by any means at any intersection will reduce accident severity and frequency.

4. There is no evidence that fewer accidents are occurring. There is in fact only evidence that there may have been a reduction in REPORTED accidents in some intersections. The reduction if any, in reported accidents, is as likely a result of the reduction of severity of accidents (not supported), and the vehicles are driveable with no report made. No law enforcement agency is called or the drivers would not wait for a responding agency.

B. Specifics

1. As the reader can see there was a 40% increase in accidents in the Salinas/APS roundabout which was included in this national study.

2. 11 "property" and no "injury" accidents prior to the roundabout to an increase of 17 total accidents including 2 injury after conversion to roundabout. The authors describe the Salinas/Sycamore Canyon/APS roundabout installation as a failure. This admitted failure is said to be because prior to conversion to a roundabout all five entry points were controlled by stop signs (all way stop). This stop sign controlled design is concluded to be as safe or safer than the roundabout configuration.

C. Relation to Milpas

1. The Milpas roundabout was too new to be included but as you know our experience confirmed by the City of Santa Barbara Police Department accidents statistics, it is very likely that safety is not improved by roundabout conversion except in rural, low volume and often higher speed uncontrolled or partially controlled intersections.

D. Conclusions

1. The authors admit roundabouts are not particularly safe or efficient for busy high volume urban intersections, particularly when used also by bicycles, pedestrians and mixed types of vehicles such as trucks and buses.

2. The authors admit that roundabouts may not be as safe as conventional intersections for pedestrians and bicyclists. The context or location of any roundabout as well as its design, are critical to the determination of whether or not to install a roundabout.

3. The attempts to estimate or predict the likely reduction in accidents that would or could result from roundabout conversion is a virtual impossibility because of elements of chance and changes in volume and traffic patterns brought about by the roundabout (and demographic changes of population).

4. Traffic volume and relative speeds are more important factors in the likelihood of accidents than any other element(s). e.g. The pre roundabout traffic accident "patterns" were non-existent 1995 - 1, 1996 - 6, 1998 - 0, etc. There are many intersections which have gone years with no accidents reported then suffered a spate of 3-4 accidents in one year. Often these are pure coincidence, other times the result from changing temporary physical conditions , overgrowth, visual obstruction, or weather conditions and the volume of vehicles using that intersection during that period or season.

5. The paramount problem with the current intersection analysis is that it is pre-occupied with time delays. The level of service (LOS) approach grades intersections on an A through F scale based entirely on delay. i.e. whether queues develop, and at signalized intersections whether all waiting vehicles "clear" the intersection in one or more signal cycles, and how many seconds they must wait. This approach fails to consider safety, comfort and convenience factors, non-reported accidents, new accidents, fear and road rage incidents.

6. In addition the Americans with Disabilities Act (ADA) provides that no government may alter or modify any existing public facility so that it results in a condition less safe or convenient for those with a disability. Signalized intersections like the Milpas/101 intersection provided protected intersections right of way for pedestrians using "walk", "Don't Walk" lights. To remove these protections for a system that leaves a pedestrian to fend for themselves (that is cross only when they think it is safe to do so) is a violation of the A.D.A.

The proponents of roundabouts often know little about any of these factors.



 

 

Trucker's view of calming in the U.K.

· By: Gordon Pye
· Date: 1996-09-09


To use fuel efficiently, the driver of a heavy vehicle needs to store the energy contained in the vehicle. Traffic calming is perhaps the greatest waste of fuel ever devised. One new roundabout, causing an average speed reduction of 30 Kph, traversed five times loaded at 32.5 tonnes, and four times at 11.5 tonnes, used on average 2 gallons extra fuel per day. This can be proved by mathematical calculation, but I have never seen the equations in any text book. I have undertaken a rough calculation of the extra fuel used by causing a heavy vehicle to stop or slow. The roundabout calculation shows that fuel consumption is doubled over a certain road section from the start of braking, to the end of acceleration. This will be true for all vehicles forced to stop or slow. The same principle applies to all vehicles if the stored energy has to be wasted through the brakes.

I have recently heard that all new or improved major roads in Lancashire must have roundabouts at all junctions with less than 1 km vision in both directions. The roundabout recently constructed on the A59 near Clitheroe is so tight for Heavy Goods Vehicles (HGVs), that it will reduce speed to under 20 Kph for vehicles traveling up grade. It is also guaranteed to increase congestion, therefore using extra fuel. Even though the road is dual carriageway, the roundabout has only one true lane through it, unless everyone drives a Nissan Micra. If anyone had deliberately set out to design a death trap for cyclists, it is doubtful whether they could have made a better job of it. Drivers at a nearby cement works are experiencing vehicle stability problems at low speed in the eastbound (empty) direction. Their union representatives have asked the company to contact the local highway authority in an attempt to get the roundabout modified into a safer layout.

Miles per Gallon is not a true measure of fuel consumption. The true measure is grams per kilowatt hour, as used by transport engine manufacturers. The total amount of time under power is the factor which determines Mpg. Almost all internal combustion engines are most efficient at or near full load. This is because the heat lost through cooling and the exhaust is almost constant under any load condition.

Developments such as power steering, air conditioning and even electric windows all consume extra fuel. Air conditioning is perhaps the most environmentally damaging development, as it consumes a vast amount of extra fuel. Average family cars fitted with power steering may use up 10% more fuel than non fitted vehicles. The addition of air conditioning may increase fuel consumption by a further 15% or more?

Factors such as these can make recent theoretical improvements in thermodynamic and emission performance quite meaningless. Almost all new cars come with power steering and or air conditioning as standard. If the public were aware of the extra pollution caused by these extras, perhaps the manufacturers would be forced to abandon them as standard.

Road safety is usually the reason used to justify traffic calming schemes, but most are designed to slow the average family car. To the HGV driver, most new junction layouts cause more potential safety problems than the ones they replaced. Road design appears to have more to do with the need to accommodate standard kerb (curb) components, than the physical needs of long vehicles. Modern road design takes no account of the turning space that a long or articulated vehicle needs. The junctions and roundabouts are quite adequate for the needs of a car, but the lanes are usually impossible for HGV's or buses to follow. Apart from causing additional safety problems for other road users, bad road design also increases wear and tear, driver fatigue, and thus the ultimate safety of the vehicles themselves. I have been reliably informed that new traffic calming under rail bridges is largely responsible for the recent high number of bridges hit by high vehicles? The present situation is probably the result of a whole generation of road designers being taught the perverse theory that, "making roads more dangerous makes them safer."

Inappropriate traffic calming on routes frequently used by HGV's and buses causes additional problems. Once wide roads which once caused few problems are now filled with pinch points and traffic islands. Most new roads are a series of traps to catch cyclists and incompetent car drivers. The specified minimum safe distance from the kerb was 18 inches when I passed my HGV test in 1982 . This distance is impossible to achieve where traffic calming measures exist. Traveling close to the kerb is bad for pedestrians, especially when pools of water form in holes or hollows. The A59 at Copster Green between Preston and Clitheroe carries a large amount of extra HGV traffic from the cement works, and roadstone quarries at Clitheroe, and the quarries in the Craven area of North Yorkshire. The road was improved during the 1960s and did not require resurfacing until about 1990. Two years ago, Lancashire County Council introduced traffic calming measures at Copster Green. In addition to a 40 Mph speed limit, several traffic islands were built into the centre of the wide road. Since the introduction of central traffic islands, all HGVs are forced to travel close to the nearside kerb. This has caused excessive damage to the nearside of the road in both directions. Almost all the drain grates have been pounded well below the road surface and the surface is cracking up next to the kerbs. This creates additional dangers for cyclists.

In just a couple of years, the traffic islands at Copster Green have caused the same amount of damage which one would expect after about 15 years or more for a similar wide road. The extra maintenance of the carriageway must place extra demands on natural resources. Patching roads usually means that more material than needed is ordered. The spare (usually at least a ton) ends up being tipped back at the quarry, unless the driver can find someone who has a use for it, then only if its the last load of the day.

Traffic Calming encourages lunatic drivers to attempt an overtaking maneuver on the approach to pinch points, or roundabouts . It is impossible for vehicles to follow a true safe line through any of the obstacles after the road alleged safety improvements. Road design is a major factor in overall road safety, but is seems as though no one is prepared to take this important factor seriously. Many accidents involving goods vehicles are a direct result of poor road design. Adverse cambers and other ideas designed to slow traffic are built in to almost all new roads.

Road design appears to be immune from scrutiny by accident investigators, even though it is the probable cause of many accidents. Most new road junctions are designed to cut the speed of vehicles using them. However, designing roads with impossibly low safe speeds is counter productive in the case of heavy goods vehicles. Being crushed by a goods vehicle ( or its load ) traveling at 5 Mph leaves you just as dead as one traveling at 50 Mph. Modern road layouts almost all incorporate features which can set up a pendulum effect in high vehicles and lead to slow speed roll-over. The driver can counteract this effect by use of the accelerator to provide a force to cancel out the effect. Being forced to apply the brakes, or cut the accelerator at the wrong moment during the pendulum cycle is extremely dangerous.

Continual braking and accelerating also causes the brakes of HGVs to rapidly overheat and "fade" thus significantly increasing the stopping distance in an emergency. This factor is compounded on vehicles fitted with ABS, but that's another story.

Air pollution could also be reduced by reversing the present theory of traffic management by traffic calming. In many cases this would cost very little as it mainly involves altering the phasing of traffic lights. The replacement of all small diameter roundabouts on major roads would also produce a useful reduction in emissions from all vehicles. Part time traffic signals and "free give way" left turns could replace many current roundabouts and other permanently controlled junctions, without a significant reduction in safety.

The recent development of speed cameras offers a unique opportunity to depart from the use of potentially dangerous road layouts to control the speed of vehicles. Roads could once again be laid out to suit the true safe turning characteristics of vehicles, as demonstrated when snow obscures the lane markings. By getting rid of the need for small roundabouts and any other forms of traffic calming, land, fuel, tyre wear, and other vehicle maintenance is saved; road maintenance will also be less frequent and easier. Thus we would likely see cost savings for everyone and benefit to the environment all round.End of Article

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