Share of Reverse Commute Trips Growing
Metro is focused on solving one of the region’s most pressing mobility issues – increasing the capacity of the system to handle more trips through the core (defined below) of the Metrorail system. While Metro’s planning staff has been conducting technical analyses and searching for the best solutions for some time, we also asked for ideas for increasing core capacity from you as well as discussed the potential for new lines, new connections and expanding to all 8-car trains during peak periods.
There are also operational strategies Metro could employ to provide more trips on the rail system without expanding capacity. Among the various options is to promote and encourage more “reverse commuting” where commuters travel opposite the peak travel direction in seats that would otherwise be empty. Data show that reverse commuting has already increased over the past 10 years and many speculate that it will only increase further as the region builds more suburban town centers near Metro and as Metro begins operations on the Silver Line later this year.
As a primer, allow us to define what Metro means by “the core.” Because we’re interested in assessing growth of trips that don’t impact core capacity, we consider the “core” as the stations and tracks just inside the maximum load point of each rail line. Therefore, we won’t consider a trip a “reverse commute” trip if it starts just outside the max-load point, travels through the core and out the other side. This definition of “core” is more restrictive than that used in other analyses as it is defined by the maximum load points on each rail line.
The next step is to define different trip types, including types of Reverse Commute trips. The diagram illustrates the six different types of trips defined for this assessment, including one traditional trip type and two reverse commute trip types:
Once the trip types are defined, each Origin-Destination (OD) pair is assigned one trip type. For example, a trip from Foggy Bottom to Metro Center is a #6, core-to-core trip and a trip from Shady Grove to Gallery Place is a #1, traditional commute into the core. Once the trip typology is applied, we can then assess the number of trips making each type of trip. This was done for the 2002 and 2012 Metrorail Ridership Surveys, with the results below.
AM Peak Ridership is up about 10% system wide between 2002 and 2012, but the traditional commute pattern (suburb to core) which makes up 50% of our AM Peak ridership only increased by 2% over the same time frame. Reverse commute trips are up to 8% of all AM Peak Metrorail trips from 6% in 2002. The percent change in absolute trips has increased by 34% to 49% depending on the trip origin. See the table below:
|Commute Types||2002 Share||2012 Share||% Change 2002 to 2012|
|Non-Core Peak Direction||8%||11%||45%|
|Same Line Reverse||3%||4%||49%|
Basically, the number of trips using Metrorail out-of or away-from the core increased dramatically by approximately 40%, though their share of all trips remains relatively low.
Looking at the destination stations of reverse commute trips can give some insight as to why this pattern has changed. The map below shows the Top 10 destinations for AM reverse commute trips in 2012. Seven of the top 10 are suburban work locations in Montgomery and Arlington Counties and the City of Alexandria. The remaining three are stations closer in. Several factors are likely at play here:
- Job growth near Metro stations in suburban centers.
- An increase in interest in living in walkable, urban communities has increased the number of residents near these “core” stations.
The data used for this analysis is also available for download.What other changes in trip patterns can you find between 2002 and 2012? What reasons might you propose for these changing patterns?