4% less vehicles yielded 36% reduction in congestion in DC Metro
If you didn’t hear, the Pope Francis visited the United States recently, and of course a stop at the seat of American power, Washington DC was on his itinerary. His tour included a host of cities across the country, and in each and every one city officials were tasked with safely addressing the predicted massive increase in traffic volume. In the DC area particularly, there was increased scrutiny regarding congestion, traffic patterns, and travel times for commuters during peak hours. The entire summary can be found at http://www.mwcog.org/transportation/weeklyreport/2015/files/10-20/PapalVisit_FullMemo.pdf, if you like reading graphs and charts. The study was done with commercially available data gleaned from the GPS capabilities of smart phones and driver navigation units and spanned the week of the papal visit along with the week preceding.
What the study found is that ‘modest reductions in driving during peak periods can yield dramatic improvements in travel conditions’. That’s not an exaggeration. In some cases, traffic volume reductions of only 4% yielded congestion reductions of as much as 36%. That’s a congestion reduction factor of 9x!
That’s all well and good, but to put that in terms of driving time, inbound traffic on the I-395 between the Beltway and the Potomac took a mere 12 minutes for commuters as opposed to the normal rush hour travel time of 44 minutes. Not very many of us are in a rush to get to work, but shaving a half hour off the time spent sitting in traffic sounds pretty enticing. It wasn’t just peak hour traffic on I-395 that saw an improvement in congestion; Maryland’s I-270 saw a drop from 38 minutes to a whopping 11 minutes for commuters from the ICC to the Beltway.
Remember, all of these improvements in congestion came from only a 4% drop in volume. What if that volume decrease could be achieved every day? What if the time savings of over thirty minutes could become the norm?
The answer lies in minor changes to driving and work habits. In response to the anticipated traffic that the papal visit was predicted to produce, many employers instituted temporary telework policies and flexible hours for commuters. Together these practices created the effective decrease in traffic volume, and the related reductions in congestion. Carpooling, or slugging, can also regularly decrease volume during peak hours. Collaborating with coworkers can not only reduce fuel costs, but can also reduce commuter volume during peak hours. The next time you’re sitting in traffic with your empty car, remember that it only takes some small changes to make a big difference.