T.F. Green Airport Improvement Program - FEIS Chapters - PVD

T.F. Green Airport Improvement ProgramEnvironmental Impact Statement and Final Section 4(f) EvaluationEffects on VMT and VHTThis section documents the effects of the No-Action Alternative on vehicle trip lengths and durations. Adecrease in VMT indicates shorter trip lengths, more direct routes of travel, or less traffic demand through thearea. A decrease in VHT indicates shorter trip durations, travel on less congested routes, or less traffic demand.Assuming traffic demands are held constant, it is possible to show increases in VMT with correspondingdecreases in VHT if drivers choose longer trips that bypass congested roadways. Similarly, if drivers choosemore congested roadways that are more direct over longer ones that are uncongested then there would be anincrease in VHT and a decrease in VMT.Changes in VMT and VHT were determined using the Statewide Model for the model’s traffic analysis zones(TAZs) that generally comprise the Study Area. VMT is predicted to increase by 8.5 percent by 2015,11.4 percent by 2020, and 17.2 percent by 2025 under the No-Action Alternative when compared to the BaselineCondition. VHT is expected to increase by 11.4 percent by 2015, 18.1 percent by 2020, and 28.4 percent by 2025under the No-Action Alternative when compared to the Baseline Condition. These increases in VMT and VHTare attributable to more vehicle trips on the roadway network traveling on more congested routes.Effects on Peak Hour Traffic Flow (Level of Service)This section documents the No-Action Alternative morning and evening peak hour traffic flow. At twolocations, existing LOS E or LOS F capacity constraints would be exacerbated by increased traffic under theNo-Action Alternative:• Post Road (U.S. Route 1) at Lincoln Avenue – During the evening peak hour, the overall intersection woulddegrade from LOS E to LOS F under the No-Action Alternative in 2015, 2020, and 2025. This is primarily theresult of a heavy eastbound left-turn volume (410 to 440 vehicles, depending on the year) fromLincoln Avenue onto Post Road that is not provided a protected traffic signal phase.• Airport Road at Warwick Avenue – During the evening peak hour, the overall intersection would continueto operate at LOS E under the No-Action Alternatives in 2015 and 2020. Under the No-Action Alternative in2025, the intersection would degrade from LOS E to LOS F. This is primarily the result of heavy volumes onall approaches where the signal is operating near capacity.The No-Action Alternative (2015, 2020, and 2025) would result in LOS E or LOS F conditions at seven locations:• Post Road (U.S. Route 1) at Airport Road – During the evening peak hour, the overall intersection woulddegrade from LOS D to LOS E under the No-Action Alternative in 2025.• Airport Road at Commerce Drive – The added traffic from planned development off Commerce Drivewould result in LOS F operations from LOS B in the evening peak hour in 2015, 2020, and 2025.• Airport Road at Warwick Avenue – During the morning peak hour, the overall intersection would degradefrom LOS D to LOS E under the No-Action Alternative in 2015, 2020, and 2025. In the evening peak, theintersection would continue to operate at LOS E under the No-Action Alternatives in 2015 and 2020. Underthe No-Action Alternative in 2025, the intersection would degrade to LOS F during the evening peak hour.Chapter 5 - Environmental Consequences 5-123 July 2011\\mawatr\ev\09228.00\reports\FEIS_Final_July_2011\PVD_CH05_Environmental_Cons_JUL_2011.doc