Roadway safety data and public works: it’s fundamental Stephen W. Read, P.Eng., Highway Safety Improvement Programs Manager, Virginia Department of Transportation, Richmond, Virginia; Michael B. Sawyer, P.E., Senior Highway Safety Engineer, Vanasse Hangen Brustlin, Inc., Richmond, Virginia
ccording to a recent American Automobile Association (AAA) study, the cost of motor vehicle crashes in urbanized areas was close to $300 billion in 2009. For the same year, a Texas Transportation Institute (TTI) congestion study for those same urban areas pegged the cost of congestion at nearly $100 billion. Practicing professional engineers go to work every day to assist planners, city managers and other public works professionals in their local communities to stay focused on safety and to deliver crucial countermeasures to address severe crashes. Innovative solutions and unique approaches are used to save lives and prevent serious injuries from motor vehicle crashes. Public works agencies and professionals are also tasked with any variety of roles related to roadways safety—from planning to operation and maintenance. Using roadway safety data can help inform local decision-making processes and make policy and program decisions for roadway safety improvements. In the past, an engineer would start with a traffic crash database to find concentrations of severe crashes. Now, with the use of roadway inventory data, engineers are pushing to expand how they determine where their low cost, systemic safety countermeasures would be most effective within the jurisdiction for which they are responsible. This more robust approach reflects a renewed emphasis on improving and combining roadway inventory data with crash data. These combinations include looking at 132 APWA Reporter
August 2012
dangerous horizontal curves, as well as critical intersection or facility types. Recent research demonstrates that a small subset of the roadway inventory can be extremely effective when combined with related crash data. Having an extensive understanding of the existing conditions is preferred, but starting with some basic roadway inventory data can provide a better focus to save lives. Increasingly, the Fundamental Data Elements (FDE) shown below are being used to save lives in communities across the country, yet some engineers and
public works professionals may not have heard about how powerful a “small” amount of information can be. So how can transportation agencies use these FDE with the Highway Safety Manual (HSM) or SafetyAnalyst to save lives?
The Virginia Experience Like other transportation agencies, the Commonwealth of Virginia is on a journey towards zero deaths. Over the past five years, Virginia has
Fundamental Data Elements Roadway Segment Intersection Segment ID* Intersection ID Route Name* Location Alternate Route Name* Intersection Type Route Type* Date Opened to Traffic Area Type* Traffic Control Type Date Opened to Traffic Major Road AADT Start Location* Major Road AADT Year End Location* Minor Road AADT Segment Length* Minor Road AADT Year Segment Direction Intersection Leg ID Roadway Class* Leg Type Median Type Leg Segment ID Access Control* Ramp/Interchange Two-Way vs. One-Way Operation* RampID* Number of Through Lanes* Date Opened to Traffic Start Location Interchange Influence Area on Mainline Ramp Type Freeway AADT* Ramp/Interchange Configuration Ramp Length AADT Year* Ramp AADT* Ramp AADT Year *Highway Performance Monitoring System full extent elements are required on all Federal-aid highways and ramps located within the grade-separated interchanges, i.e., National Highway System (NHS) and all functional systems excluding rural minor collectors and locals.
