Image by Adam Fagen licensed under Creative Commons.

There’s been no lack of coverage of the peak $40 toll for the 10-mile stretch of I-66 that converted to HOT lanes this week. As a single occupancy driver who commutes to DC from the Virginia suburbs outside the Beltway, I was curious to crunch the numbers to find out how the numbers shake out — beyond the shock of the peak-of-the-peak pricing.

A few things changed for drivers with the introduction of these new HOT lanes, but the biggest change was for single-occupancy vehicle drivers. Previously they were restricted from driving on I-66 eastbound between 6:30 am and 9:00 am and westbound between 4:00 pm and 6:30 pm. Outside of these time restrictions, they were free to access the roads anytime.

In converting I-66 inside the Beltway from HOV2 to Express Lanes, the time period for restricted access increased to 5:00 am to 9:30 am and from 3:00 pm to 7:00 pm. However, now single occupancy drivers may use the lanes if they pay a toll.

The I-66 Express Lanes website provides historical estimates of their tolls, so I decided to compare them with the actual prices thus far. I recorded the cost over 15-minute intervals from the longest length between Washington and just outside the Beltway over the first three days of the new HOT lanes. After analyzing them, what I found is a mixed bag of pros and cons for drivers.

Variance of I-66 HOT lane tolls charge over time each day. Image by the author.

Here's how the original estimates stack up to the actual costs

Two years ago, the Virginia Department of Transportation (VDOT) estimated that the average toll could be $6 each way. At the time, opponents pointed to VDOT’s estimate that the tolls could hit as high as $17 for a round trip during the peak of the peak.

Indeed, over the first three days, the westbound lanes had an average toll of $7.43, with an average daily peak of $11.83.

However, the eastbound lanes had a much greater variance from those 2015 estimates. The three-day average toll was $16.08, and average peak fare on those days was $32.67. It’s worth noting that one Wednesday the average eastbound price was at its lowest rate of $12.39, which was about a third of what it was Tuesday.

2015 VDOT Image showing estimated tolls during peak periods inside the Beltway. Image by Virginia Department of Transportation.

VDOT expects it to take a month or two in order to determine the new driving patterns caused by the HOT Lanes, but over the first three days I identified a few early trends.

Driving early isn’t always better

Traditional logic would say that the earlier you travel before the rush hour the better the deal, but this doesn’t seem to be the case. The average eastbound rate at 5:30 am was $9. Just fifteen minutes later, the average over three days was $3.75. It’s not until 6:45 am that the three-day average rate was more than it was at 5:30 am.

Graph shows the three-day average for morning eastbound traffic. Orange bars represent time previously reserved for only HOV 2 vehicles. Green bars represent the time periods previously without restrictions. Image by the author.

At an average rate of $5.92, the cheapest westbound time was at 6:30 pm. At 4:15 pm, seventy-five minutes after tolling begins, the average was $6.25. Equally as surprising is that the average rate between 4 pm and 5 pm was actually 27 cents cheaper than the rate between 3 pm and 4 pm, $6.69 cents and $6.96 respectively. This is important to note, because prior to Monday, solo drivers couldn’t use westbound I-66 between 4 pm and 6:30 pm.

Graph shows the three-day average for evening westbound traffic. Orange bars represent time previously reserved for only HOV 2 vehicles. Green bars represent the time periods previously without restrictions. Image by the author.

The pricing really is dynamic

Similar to the 495 and 95 Express Lanes, dynamic pricing is used to regulate the lanes to maintain a constant speed and avoid overcrowding. Every six minutes a new price is developed in order to maintain an acceptable speed. Over the first three days, we saw some large fluctuations that proved just how dynamic the pricing could be.

Tolls hit their zenith at $34.50 for eastbound solo drivers on Monday, sparking a social media firestorm. However, during the hour prior, we saw wild swings in pricing. At 7:45 am, the toll was $28.50. Just twenty-one minutes later, at 8:06 am, the price had dropped to $17.25. By 8:30 am, it made it to $30 before hitting its peak for the day ten minutes later.

So what does this all mean?

The change from HOV to HOT lanes seems to have its pros and cons for different people. For those who used to travel solo outside of the old peak hours and now have to pay a toll to drive in, the HOT lane conversion is an obvious con. There’s also the potential for solo drivers to overwhelm other local roads in order to avoid the new toll during these expanded hours.

However, one of the big advantages offered by this program is the availability for everybody to use I-66, regardless of what time it is.

Currently, the morning rush hour period is cost-prohibitive for most, but the afternoon rush period, which previously prohibited solo drivers, is much more affordable. The three-day average at 5:15 pm was $7.83. The average rate for those using the roads between 3 pm and 5 pm was $6.82. Neither of these are too far off from the 2015 estimates.

Daily average of the tolls in the morning and evening. Image by the author.

Faster speeds are also an added perk of the new system. This not only is an advantage for solo drivers paying tolls, but those who choose to carpool. VDOT reported that the average speed during Monday’s rush hour was 57 miles per hour, compared to 37 mph at the same time a year ago.

What also shouldn’t be overlooked is what the tolls will be going to. Besides paying for the installation and upkeep of the tolling system, this will also pay for multi-modal transportation improvements with the goal of reducing traffic. This could include expended bus service, park-n-ride lots, WMATA improvements, and improved roads. For a region with some of the worst traffic in the country, these types of improvements are greatly welcomed.

The initial sticker shock of the peak-of-the-peak fares is tough to get past, but when we are looking at this program, let’s not overlook the positives as well.

Clarification: Average tolls in the article are calculated based on the 15-minute increments for the entire length of the I-66 lanes.

Mike Grinnell has worked in the design and construction industry since 1998, and relocated to DC in 2001.  He has a BS in Building Construction from Auburn University and studied Economic Development in grad school at Virginia Tech.  Mike served two terms on the Potomac Yard Design Advisory Committee before moving to West Springfield with his wife and two daughters.