tfp3

"THE FINE PRINT"

The musings of Michael Schrader

                            THE POLITICS OF SPEEDING
(Published 1994 in the Farmington Press-Leader; posted in toto with Preface and Epilogue 5 July 2001)

PREFACE -- One of the crusades that I have fought for over the past decade as an engineer is the concept of designing roads to fit the speed at which you motorists to drive. If you want motorists to go 30, design to road for 30. Unfortunately, we overdesign our roads, which encourages speeding, as motorists will tend to drive what they feel is the safe and proper speed depending on the design and ignoring the posted speed limit. Here in Texas, for example, we have six lane divided streets with posted speed limits of 30 and 35 and most motorists ignoring these speed limits. The ultimate result, then, is a general cynicism and disregard of speed limits. This is a nationwide problem that can be rectified through education and litigation.

       One of the most frequent concerns I have heard as a traffic engineer is what to do about speeding. The solution that is most often implemented to solve this problem is the lowering of speed limits. Lowering of speed limits is a winning situation for politicos, as it appeases voters while giving the illusion of solving the problem. I use the word illusion, because that is what speed limits provide: an illusion of speed control.
      Even state legislators have gotten into the act of lowering speed limits. Because of a complaint by a constituent that speed limits are too high, a St. Louis County state representative has vowed to lower speed limits in South County, despite the objections of both the county and state highway departments.
      How are speed limits determined, anyway? Proper speed limits should reflect the speed that 85 percent of the motoring traffic will not exceed, as it is impossible and unrealistic to expect 100 percent of motorists to drive reasonably. (There's always one in every crowd who pushes the limit.) This "85th percentile speed" (as it is called) is commonly referred to as the "reasonable and proper" speed.
      However, it is not politically wise to post speed limits at the "reasonable and proper speed," as posting proper speeds usually cause a severe, and negative, reaction from concerned parents, residents, schools, etc. For example, the new and improved Hillsboro Road, when complete, will probably (this is an educated guess based on my years in the traffic engineering profession) have an 85th percentile speed between 40 and 45. However, to post a 45 speed limit on Hillsboro Road would cause such a public outcry as to be an unreasonable option. Thus, the speed limit will probably be arbitrarily set at 30 or less. Of course, most motorists will be travelling 45, but at least there will be the false sense of security that the speed limit is 30. Once the road is opened, the Farmington police will be able to make a king's ransom on speeding tickets.
      Most speed limits are arbitrary, and do not reflect the safety of the roadway. That is why most speed limits are ignored. For example, why does the speed limit on the new 32 Bypass of Park Hills suddenly drop from 55 to 30? Does the road really become that much more dangerous? The 30 (as well as the 55) was arbitrarily determined by politicians and does not reflect the safety of the roadway. Does 55 really become more dangerous north of Barnhart? I don't think so, but the speed limit drops from 65 to 55. Completely arbitrary.
      Studies done over the years have proven time and time again that people drive what they consider to be the safe speed, regardless of the speed limit. Other studies have shown that many people do not even know what the speed limits on local roads are, as they are so familiar with them that they know how fast they can drive on them. When I was a city traffic engineer in Illinois, I changed the speed limits on several streets (much to the chagrin of co-workers who swore I was creating new freeways). The result? Speeds did not change. Why? Drivers had already determined the safe speed and ignored the signs. One year after the change on one street, a motorist called and said he drove that street every day and wondered why we recently changed the speed limit. I told him that motorists ignored speed limit signs. He told me I was full of bull. When I told him that the speed limit had been changed over a year ago, and that he had not noticed the change, either, his tone changed from belligerent to apologetic. He had proven my point.

Epilogue-- The crusade continues. Meanwhile, here in Texas, speed limits on the freeways have been lowered to help bring North Texas into compliance with air quality standards. The old speed limits were violated, and so are the new. While theoretically air quality has been helped by the reduced speed limits, in reality, it hasn’t. And the politics rolls on . . .