I-66 Multimodal Study Final Report - Virginia Department of ...

Mobility OptionsOption C1 – I-66 Capacity Enhancement Option 1As illustrated in Figure 2.12, this option adds an additional lane in both directions, with newadditional HOV restrictions applied to the new capacity (inside the Beltway only) as follows:In the peak direction, all lanes are Bus/HOV 3+ only during peak hours;In the reverse‐peak direction, one lane is Bus/HOV 2+ during peak hours, and the rest aregeneral purpose lanes; andIn off‐peak periods all lanes are open to all traffic.The HOV restrictions will be in place during the same hours as the current restrictions. Theaddition of the restricted lane in the reverse-peak direction will provide an uncongested lanefor transit vehicles, allowing for an increase in bus speeds. The widened I-66 profile willinclude three lanes total, except on the portion east of the split for the Dulles Connector Road.For this section, both the eastbound and westbound segments will have three general purposelanes and one auxiliary lane.Figure 2.12 I-66 Capacity Enhancement – Option C1Key FindingsThis option primarily eases congestion on I-66 in the reverse-peak direction, although the additionalincremental capacity is restricted to HOV 2+. The HOV 3+ restriction on all lanes duringpeak periods limits use of the new capacity in the peak direction. Other findings based on theMOEs detailed in Table 2.3 include:The percentage and amount of uncongested VMT increases in both the morning andevening peak periods due to the new roadway capacity;Total PMT in the study area increases as additional travel shifts into the study as shown inFigure 2.13;I-66 Multimodal Study 2-21