On Thursday Caltrans had an open house to discuss proposed fixes to the freeway. While the format of the meeting was less than desirable, the solution they offer does not appear to address the major problem along this corridor.
First, at Kidwell, they propose converting one mixed-flow lane to managed lanes. Then at the Solano/Yolo County line, all the way to the Yolo Causeway, they propose paving the median and adding a managed lane.
Finally, at the Causeway they propose adding managed lanes there as well, while moving the existing bike path and creating a separate bridge.
A lot of people are skeptical that simply adding traffic lanes – ten years down the line – is going to fix the problem.
Especially when the problem appears to occur due to two key factors – the increase of lanes to six and back down to three over a relatively short period creating a bottleneck that many vehicles attempt to bypass by using local roads, which in turn creates not only local traffic jams in places like Davis, but also probably contributes to the slowdown as all of the vehicles re-converge at the entrance to the Causeway.
We can see this analysis in the two presentations made by Fehr & Peers discussing Mace.
As Adrian Engel from Fehr & Peers discussed in his presentation on Tuesday, there is a direct correlation between freeway speed and the traffic that diverts onto side streets, with most of it entering onto northbound Mace and reentering the freeway around Mace.
Mr. Engel actually noted that the biggest advantage in terms of time is not to take the Dixon bypass at Tremont, but rather to go to Highway 113 and cut across via Road 29.
He explained that he and his team got onto the freeway during peak time to validate that the freeway was not the fastest way to get from Dixon to the Causeway. Five of them traveled at the same time through different routes to see if the apps and maps and Waze “were telling us the true story.”
Traveling on the freeway was indeed the longest time. Some of the other routes “were definitely faster than the freeway.” The fastest they found was Highway 113 and County Road 29 to bypass the queue. They found that to be almost 15 minutes faster.
“There are multiple ways that can be used to bypass this freeway traffic,” he said. “The software that’s giving you these alternate routes is true and we have verified are actually faster. Ultimately the solution for this problem is going to fix I-80 and getting that traffic to flow better to keep cars on the freeway. Because if you fix Mace or do something to Mace, it may just cause traffic to go in other places.”
Ultimately, he said “the solution is to fix I-80 and get the traffic to flow better.”
Caltrans acknowledged the same problem in a September 23 letter to Bob Clarke, the city’s Public Works Director.
Brian Alconcel, Caltrans District 3, Chief Traffic Operations notes: “The severe congestion on EB I-80 and the use of GPS navigation apps have allowed drivers to make real time route changes based on travel times.”
He notes that that traffic is utilizing two primary routes. The first is exiting at Pedrick and traveling to Tremont and then County Road 104 which becomes Mace. The second exits at 113 and uses Covell Blvd. to get back on the freeway at Mace Blvd. by the southbound Mace exit.
Mr. Alconcel writes: “Travel times on the local road routes were faster for almost all time periods during the PM peak period, making the local road routes more attractive options for travelers.”
Why are they finding the traffic is primarily getting off I-80 at Dixon? The problem here, as Mr. Engel explained at the October 24 meeting at Pioneer Elementary, has to do with the configuration of I-80 as you hit UC Davis and it goes from three lanes to six lanes but then it condenses back to three lanes by the time you hit Richards Blvd.
That creates a huge slow down which traffic is trying to bypass out of. There is a second bottleneck at the Causeway – but you can’t bypass out of that one. So basically what Fehr & Peers found is that by bypassing at Tremont, you save 10 minutes, and apparently going 113 to Road 29 and reentering near the levee off Road 32, you end up saving 15 minutes.
But you’re only bypassing the traffic jam at UC Davis.
The way the freeway works is that you hit the bottleneck on eastbound I-80 right after the UC Davis entrance and that continues to Richards. It then runs at three lanes the rest of the way, but there is a secondary bottleneck, depending on the day, starting around Mace and going through the Causeway.
If you stay on the freeway, you hit the bottleneck in two locations, but even if you bypass the queue at Dixon or 113, you will hit a back up attempting to get back on the freeway, whether it be at Mace or near the fruit stand near the levee, and the traffic remains slow until you are a good way across the Causeway.
Are adding managed lanes and increasing capacity going to fix this problem? I think a lot of people are justifiably skeptical on that. The other question is why there is a need to increase the number of lanes to six at that point in the first place? Re-configuring the Highway 113 and UC Davis interchanges may make a lot more sense than simply adding managed lanes.
Interestingly enough, Caltrans has data which shows that by putting the metering in at Mace, they have helped to alleviate the congestion at the Causeway, but it has apparently come at the expense of local traffic congestion in Davis.
Note, however, that in both cases the traffic congestion begins when I-80 drops from six lanes to three just after UC Davis.
—David M. Greenwald reporting