The latest I-405 express toll lane data is in and we are pleased to see that drivers between Bellevue and Lynnwood continue to see time-saving benefits in the express toll lanes. Between October and December of 2016, people who used the express toll lanes during the busiest hours of the day moved up to 24 mph faster than the regular lanes, and the express toll lanes carried up to 27 percent more vehicles per lane than the regular lanes.
|Data clearly shows that the express toll lanes are being utilized in a big way.|
While that is good news, the express toll lanes still have their challenges. Specifically in the area north of SR 522 in Bothell, demand during the peak commute exceeds the capacity with only one express toll lane. While there's no easy fix to that issue, we're working to find ways to help until a more long-term solution can be made.
Moving more vehicles during the busiest times
The Puget Sound region is growing by about 1,700 people every week and all of our roads are increasingly crowded. Like other freeways, I-405 is carrying more vehicles than it was last year. Unlike other roads, people on I-405 have a faster, more predictable choice to use the express toll lanes when they really need it.
Every weekday about 51,000 drivers choose to get in the express toll lanes. In Kirkland, where there are two express toll lanes and five total lanes, the express toll lanes represent only 40 percent of the pavement but carry 44 percent of the vehicles. In Bothell, where there's one express toll lane and two regular lanes, the express toll lane is carrying an impressive 39 percent of the vehicles.
|A look at the percentage of traffic the I-405 express toll lanes are carrying|
Of course, these statistics vary depending on when and where you are looking, but it gets more impressive when you look at the absolute busiest times and places. For example, each morning from 7:30-7:45 a.m. there are an average of 315 vehicles travelling south past the SR 522 interchange in the single express toll lane, which is 23 percent more vehicles than each regular lane. In Kirkland from 4:30-4:45 p.m. there are 74 more vehicles zipping past NE 53rd St. in each of the express toll lanes – 12 percent more – than there are in each regular lane.
Faster speeds when you need them
There is a reason so many drivers are choosing to pay the toll to use the lanes: Time savings. Vehicles traveling between Bellevue and Lynnwood save an average of 11 minutes southbound and 15 minutes northbound. That's almost 30 minutes saved round trip and about 2½ hours a week.
Overall, people in the express toll lanes moved an average of 20 mph faster than the regular lanes southbound during the peak morning commute times of 5-9 a.m. and 24 mph faster northbound during the afternoon peak times of 3-7 p.m.
|The average speed at the top of each hour during peak commute times in the express toll lanes.|
Of course, how fast you're traveling depends on where and when you are driving. Due to the different capacities in the single and double lane sections, travel times and average speeds vary a lot between these two sections. Data shows the fastest sustained speeds at the beginning of every hour during the peak commute were on the stretches with two express toll lanes.
Working to address challenges
One way that we measure express toll lane reliability is by calculating the percentage of time that vehicles in these lanes are moving at least 45 mph. The goal is vehicles moving 45 mph or faster 90 percent of the time during peak periods. Before the express toll lanes opened, vehicles using the I-405 HOV lanes were only moving 45 mph 52 percent of the time. The express toll lanes provide more reliability and vehicles are moving at 45 mph 78 percent of the time during peak periods.
When you break it down between double- and single-lane sections, you'll see why we aren't meeting the 90 percent goal. Where we built a new lane, speeds exceeded the goal 93 percent of the time between July and December. In the single-lane section where no new capacity was added, vehicles moved 45 mph 67 percent of the time.
|I-405 travelers on the stretch where there are two express toll lanes.|
reach speeds 45 mph or faster 93 percent of the time
While limited capacity combined with heavy demand is one factor in the performance of the single-lane stretch, congestion in the neighboring general purpose lanes – which causes vehicles to slow down while traveling in the express toll lanes and while trying to exit – and the very wet weather we've had are also factors.
We are working to address the challenges as much as possible. We've used express toll lane revenue to improve speeds in the regular lanes between Bothell and Lynnwood with a new peak-use shoulder lane that opened on April 24. We're also building a new merge lane near SR 527 to give vehicles space to slow down and merge without creating a backup behind them. The new lane will provide drivers a place to pull out of the express toll lane before merging into the regular lanes.
While these improvements should help specific areas, they aren't silver bullets to solve the fundamental issue with the single-lane section: There's simply half as much space and incredibly high demand for a faster trip. We need additional investment in the corridor to build a second express toll lane in the northern portion of the corridor. The latest transportation budget includes funding to continue engineering work for the potential first phase of major north end improvements, which would add a new lane and improve interchanges in the section of I-405 between SR 522 and SR 527.
Putting toll dollars to work
In fall 2016, the average toll paid for all trips on the express toll lanes was approximately $2.25 and the average toll paid during the peak periods was approximately $3.35. This is up about 35 cents from the previous quarter, continuing a trend we've seen since opening the express toll lanes in fall 2015. We've also seen an increase in the number of people choosing to pay a toll of $8 or more, which was eight percent of peak period tolls this past fall.
With all that said, nearly 70 percent of all tolls paid during peak periods in the fall were $4 or less.
At the end of 2016, the I-405 express toll lanes had generated $22.6 million in toll revenue. After expenses like customer service, operations, and maintenance, about two-thirds of this money will be spent directly on improvements to I-405, which will benefit drivers and transit riders in every lane.
Want more data? Check out the full report in our project library.