Accident Study Highway Safety Investigations

As part of a team, SIMCO performed comprehensive Highway Safety Investigations (HSI) for various Priority Investigation Locations (PILs) identified by Region 11 of the New York State Department of Transportation (NYSDOT).

The PILs identified by NYSDOT were located on the Brooklyn-Queens Expressway (BQE), the Bruckner Expressway, the Franklin Delano Roosevelt (FDR) Drive, the Major Deegan Expressway, and the Staten Island Expressway (SIE).

• SIMCO prepared collision diagrams from the police accident reports received from the State. The accident rates were computed and compared to the statewide average accident rates for similar facilities.
• SIMCO then reviewed the accident patterns to identify potential contributing factors to the high accident occurrence locations.
• JFK British Airways/TWA Terminals traffic counts
• A field investigation was also conducted within the limits of the PIL to identify deficiencies that may have contributed to the high accident rate and actual traffic movements are noted.
• Short- and long-term safety mitigation measures were developed which included improvements to existing signing, pavement markings, pavement, alignment, and roadside appurtenances.
• A safety benefit analysis was then performed for the proposed mitigations, using Forms TE-156a and TE-164.

Additionally, spot speed studies were done at certain locations as part of this contract. The spot studies were used to define the “design speed” or the maximum safe speed that can be maintained over a specified section of roadway when conditions are so favorable that the design features of the roadway would govern.