WIDER ROADS = SAFER ROADS?  

It is commonly claimed that adding lanes and making lanes wider have helped to reduce total road fatalities and injuries. It is true that as roads have been widened over the years, fatalities did decline. Researcher Robert Noland examined the effect of adding and widening lanes on both fatalities and injuries, using 14 years of data from 50 states. He found that the safety improvements resulted not from the widenings but from the aging of the population, increased seatbelt use, and improvements in medical technology. Had it not been for these factors, the "higher" standards would have made the casualty rates worse.

Noland's research findings have major implications for the cost benefit analysis of highway projects and for new Federal planning regulations that require safety to be considered as a planning factor. He presented the study in a new paper, "Traffic Fatalities and Injuries; Are Reductions the Result Of ‘Improvements' in Highway Design Standards?", at the 2001 Transportation Research Board annual meeting in Washington, D.C.

Download Noland paper PDF file. (110KB)

An earlier paper relating lane widths to safety was "Accident Relationships of Roadway Width on Low-Volume Roads" by Zegeer, Stewart, Council and Neuman. It was more narrowly focused on rural roads, but included data on shoulder width. It received the 1994 D. Grant Mickle Award, given by the Transportation Research Board for outstanding papers published in the field of operation, safety, and maintenance of transportation facilities.

The PDF file of this paper was a transformation of a paper copy sent to me by Charles Zegeer. Although there are some small formatting differences (e.g. larger type, renumbered pages), it should be otherwise the same as the original.

Download Zegeer et al PDF file. (448 KB)

A RIGHT TO SAFETY

Steve Goodrich is an electrical engineer living in Cary, N.C., where he is on the town's Planning and Zoning Board. He thinks pedestrians and cyclists have a right to safe travel on the roads, a right which he describes in an essay posted on his website: The Right to Travel by Human Power

There is a lot of interesting stuff on his website, http://sggoodri.home.mindspring.com/