Intersection Safety Study
The Indiana Department of Transportation asked Lochmueller Group (Lochgroup) to review its scoping report for the SR 56 intersection that, despite a recent widening, still experienced 28 accidents from 2003 to 2010. The initial scoping report identified two alternatives: realigning approaching roadways for an estimated cost of $730,000 or reconstructing the intersection with a roundabout costing more than $1 million.
Lochgroup’s traffic experts found that 64% of the accidents were related to “right-angle” crashes, unusually high for this intersection type. This lack of visual communication and lack of clear pavement markings/signage resulted in drivers navigating through the intersection by way of turn lane, rather than the through lane.
Lochgroup identified simple measures to significantly reduce the number of accidents such as: additional signage; relocation of existing signs for approaching traffic; pavement markings for the right/through lanes; skip dash pavement markings to delineate vehicle path; and installation of back plates on the overhead signals for better visibility.
The new approach estimated construction cost was $6,000—a savings of nearly $725,000 over the previously-scoped alternative.