Forecasts indicate congestion will continue to be concentrated in a few key segments of our region's roadways, but impact a greater share of travelers and trips.
Congested lanes make up a small portion of the roadways in the region, however the number of lane-miles in the region that are congested during peak periods is expected to increase substantially between now and 2040.
Congestion on this small portion of roadways will affect a greater share of vehicle-miles travelled as more and more trips are added to these highly traveled routes.
Congested lane miles will make up a small portion of the total lane miles in all areas of the region both today and in 2040. The total number of congested lane miles is forecast to go up in all three sub-areas with the greatest expected increase in the inner suburbs. The share of lane miles that are congested is also expected to increase in all three sub-areas, but the highest increase is expected in the outer suburbs.
Though congestion on many segments of the region’s major highway system is expected to get worse over this period of time, some segments of highway will see slight relief in congestion thanks to capacity expansions or changes in travel behavior. Major highways seeing improvements in congestion include portions of I-66 East, I-70 East, and VA-267 East.
Though a relatively small share of lane miles are currently congested, a higher share of Vehicle Miles Traveled (VMT) is currently on congested roadways. This indicates that the roadways that are congested are some of the more heavily traveled in the region. In 2040, VMT on congested roadways is expected to increase in each sub-area as well as the share of VMT on congested roadways.
Analysis completed by WMATA shows that four of five lanes entering the downtown core are expected to become congested or highly congested by 2040. Without additional capacity, WMATA estimates that the Metrorail system will reach capacity by 2040 on trips to and through the core.