Better Design Means Safer Roads
In addition to increasing capacity and reducing costs, all non-traditional intersections are thought to be substantially safer than traditional designs, due to the reduction of the number of conflict points. Conflict points have always served as a surrogate for safety (with the least number of conflict points being the safest). Traditional intersection forms typically have 32 conflict points, while most non-traditional forms have 16. Likewise, a traditional diamond interchange has 30 conflict points, while most non-traditional interchange forms have only 16.
Fewer Stops Cause Less Pollution
Many areas of the country are in non-attainment for air quality. As a result of having two signal phases, the efficiency of non-traditional designs permits more vehicles to be moving within a specified time period than the traditional multi-phased designs which operate with more delay and idling while waiting on their signal phase to turn green. Based on VisSim models, air pollution can be reduced by 25%-30%, depending on the pollutant, with non-traditional designs when compared to the same traffic volume with traditional designs.
Typically, non-traditional designs provide a win/win/win/win over their traditional counterparts by providing:
- Higher capacities lane for lane
- Safer designs with less conflict points
- Reductions in air pollutants
- Less expensive designs