Los Alamos County Engineer Eric Ulibarri, at the podium, and Public Works Project Manager Keith Wilson, seated, discuss the road diet on Trinity Drive during the County Council work session July 18. Screenshot/LADP
By KIRSTEN LASKEY
Los Alamos Daily Post
kirsten@ladailypost.com
Just how much has the road diet that runs eastward from 39th Street to Oppenheimer Street impacted driving times? According to Los Alamos County staff, not that much.
County Engineer Eric Ulibarri and Public Works Project Manager Keith Wilson presented an update on the road diet during the council work session July 18.
Ulibarri said when the road diet initially opened in June 2020, traffic didn’t seem impacted but then in 2022, Canyon Road was closed for repaving.
As a result, Ulibarri said the staff brainstormed what was going on and what improvements could be made. The traffic counters were installed to track the volume of vehicles going in each direction.
“We went from about 14,000 vehicles a day traveling on Trinity Drive overnight to 24,000 so that is a 75 percent increase in traffic,” Wilson said.
In November 2022 after Canyon Road reopened, traffic volumes returned to around 14,000 vehicles per day. More recently traffic volumes have increased to around 17,000 per day and it is speculated that once the Jemez Road/NM4 intersection is completed the traffic will decrease back to 14,000 because drivers will take the truck route. Furthermore, Wilson said he hopped into his car to personally research drive times on the section of the road diet from when the Canyon Road was opened to when it was closed. He found when driving in the eastbound direction in the morning there was very little difference.
However, he noted that traffic wasn’t at its peak. Mid-day, Wilson reported he saw a 20-30 second difference between when Canyon Road was opened and closed. This amounted to roughly a little more than 2 minutes versus 1:50. The evening time had the worst driving time for eastbound traffic. Wilson said there was roughly a minute difference on average.
Reporting on drive times for westbound traffic, Wilson said the morning times had a 30 second difference. Mid-day, there was a 15-40 second difference. Finally, in the evening, there was a 5 second difference.
“The point of showing this is basically … there was no prolonged, consistent period of congestion,” he said.
Wilson also touched on crash data. From 2014-2019, he said there were 10-12 crashes a year on this section of road. In 2020, when the road diet was implemented, the number of crashes decreased. Wilson attributed this to the road diet and COVID having less people on the road. In 2022, the number of crashes increased but that could be due to more traffic because of the Canyon Road closure, he said. Since then, the number of crashes has stabilized and decreased. He added there have been crashes involving bicyclists, but this could be due to more cyclists on the roads.
There are pros and cons to the road diet, Ulibarri said.
The pros, he said, include a continuous center lane. This allows for a “storage” lane for left turns, a two-stage crossing ability for cars turning into traffic in either direction from the side streets, and access availability for emergency vehicles.
Furthermore, Ulibarri said the road diet is a traffic calming feature, meaning it slows traffic down but still allows it to flow. Plus, it reduces conflict points, which mean less rear-end crashes and less right-angle crashes.
“It really brings about a community- focused complete street, which is one of our goals,” he added.
For example, it gives bike lanes in both directions and provides a pedestrian buffer. There also are bays for transit buses near 36th Street planned.
Finally, Ulibarri said a new left turn at the east entrance of Los Alamos Medical Center was able to be implemented as part of the road diet.
Cons include having the capacity issues on the Diamond Drive/Trinity Drive intersection remain unsolved. Plus, drivers’ expectations changed.
“Motorists become accustomed to four lanes and now all of a sudden they have two lanes or one way in each direction and there’s a perception that there is less capacity on the roadway,” Ulibarri said.
Also, the planned pedestrian refuge in the center lane can be an issue with an emergency vehicle that could also be there, too. The whole idea for the road diet started with a New Mexico Department of Transportation (NMDOT) grant for pedestrian and ADA improvements, road preservation and The Hills apartment complex, Ulibarri said.
In 2019, the County transportation board requested that an analysis of a road diet be included in The Hills complex off-site traffic study. Ulibarri added that later in 2019, the transportation board recommended that a road diet be installed on Trinity Drive. Council initially voted against the road diet in May 2020 but then reversed its decision in June 2020.
The markings for the road diet were implemented on June 11, 2020.
