Recent traffic management tests carried out by city staff and consulting firm Kimley-Horn have revealed that two of the proposed traffic improvements sought by residents and Sedona City Council members — the closure of the State Route 179 crosswalk near Tlaquepaque and the addition of a signal light to the “Y” roundabout — are liable to have little or no effect on congestion and travel times.
City staff and Kimley-Horn consultant Andrew Baird presented updates to council on Oct. 22 and Nov. 13.
Step This Way
Residents, council members and city staff have repeatedly proposed closing the crosswalk near Tlaquepaque on the theory that it will reduce interference with northbound and southbound traffic on State Route 179 and eastbound State Route 89A along Cooks Hill. The city has reached an agreement with the Arizona Department of Transportation, which controls the right-of-way, under which ADOT will do so if the city can prove the alternate pedestrian crossing beneath the State Route 179 bridge has rendered the at-grade crossing unnecessary.
On July 6, the city closed the at-grade crosswalk from 11 a.m. until 2 p.m.
“The northbound volume at [Tlaquepaque] decreased on average the same amount, about 10 vehicles per 15 minutes, from during the metering simulation, and closing of the pedestrian crossing, to after,” the Kimley-Horn report stated. “This indicates that the closing of the crosswalk did not affect the throughput at the ‘Y’ as was observed.”
After the crosswalk was closed at 11 a.m. on July 6, by 12:10 p.m., southbound traffic on SR 89A had backed up to Airport Road according to the Sedona Police Department, while on the previous day, when the crosswalk had not been closed, “SR 89A backup was never past Mariposa [restaurant], per police.”
On State Route 179, northbound travel times from the crosswalk to the “Y” were 4 minutes 6 seconds at 1:30 p.m. and 3 minutes 15 seconds at 2:20 p.m. on July 5, with the crosswalk open to pedestrians, compared to 7 minutes and 52 seconds at 11:23 a.m. on July 6, with the crosswalk closed.
While the Kimley-Horn report did not provide raw data for vehicle counts, the included graphs indicated that the volume of traffic passing the crosswalk declined slightly while the crosswalk was closed and rebounded after the crosswalk was reopened.
During the Oct. 22 council meeting, Mayor Scott Jablow said that the empty crosswalk was “causing its own issues” by prompting drivers to slow down on approach. “People almost came to a stop as they were approaching the crosswalk,” Jablow said.
“On social media this weekend, people were ecstatic because the crosswalk was closed, and they thought that traffic was brilliant,” Vice Mayor Holli Ploog said.
“It may be a while before it’s shown that a full closure is necessary,” Deputy City Manager Andy Dickey said. “We did a warrant analysis at one point to show ADOT that the at-grade crossing was needed three years ago.”
“I don’t want extensive delays,” Councilwoman Kathy Kinsella said.
Kimley-Horn representatives estimated that testing of the crosswalk will continue through October 2025.
“We’re getting to a point where we have enough data to show that it’s helpful having it closed,” Dickey subsequently argued on Nov. 13, but then added, “even during high congestion season … there are times where we likely could need this crosswalk to be a usable facility.”
Director of Public Works Kurt Harris suggested a future median to deter jaywalking might consist of an array of rusted metal vines to complement the design of the highway bridge.
“How about cactus?” Councilman Brian Fultz asked. “Lots of nice prickly cactus?”
Jaywalking is legal in Arizona per Arizona Revised Statute §28-793, which requires only that pedestrians yield to vehicles in a roadway. City traffic control assistants, as they are not uniformed, sworn police officers, do not have the ability to stop pedestrians from using a crosswalk.
Fultz asked during the Oct. 22 meeting if it was time for the city to start prioritizing the construction of pedestrian overpasses in order to eliminate the highway crosswalks.
“I think it would be good to start looking at that,” Dickey said. “The viewshed impact is quite a controversial issue that we will need to overcome.”
In the city’s most recent budget survey, 80% of respondents indicated that they were opposed to the construction of pedestrian overpasses.
“It was pooh-poohed rather strongly,” Fultz said of the survey responses. “I don’t think there was sufficient context provided.”
Signaling a New Direction
The Kimley-Horn traffic study also experimented with having the Sedona Police Department partially block the “Y” roundabout on specific days in order to simulate the installation of a signal light at the roundabout, a concept that Jablow described as a “key concern” for him.
“The travel times confirm field observations of northbound SR 179 being negatively affected by the metering simulation while the northbound SR 89A” — i.e., Airport Road to the “Y” roundabout — “being positively affected by the metering simulation,” the Kimley-Horn report concluded.
For July 5 and 6, the study results showed that controlling roundabout traffic so as to prioritize northbound SR 89A traffic flow reduced travel times from Airport Road to the “Y” from nine-and-a-half to four minutes on July 5, and from eight to six minutes on July 6. As a result, northbound travel times on SR 179 from Schnebly Hill Road to Forest Road increased from eight to nine minutes on July 5, and from 12 to almost 14 minutes on July 6.
Confirming the July results, the simulated signaling again reduced average travel time from 5.6 minutes to 3.1 minutes on Sept. 2, and from 12.3 minutes to 10.9 minutes on Sept. 3, for the Airport Road to “Y” SR 89A stretch. In the other direction, it increased average travel times on SR 179 from Bell Rock Boulevard to the “Y” from 16.5 minutes to 16.7 minutes on Sept. 2, and from 20.3 to 23.2 minutes on Sept. 4.
Southbound SR 179 travel times from the “Y” to Canyon Drive showed minimal change as a result of the simulated signal before 3 p.m. during the Labor Day weekend, with the average travel time of about four minutes controlled or uncontrolled on Saturday rising to around seven minutes by 6 p.m. on Sunday.
Another simulation, using a portable temporary signal rather than police officers, will be conducted over Thanksgiving holiday weekend.
“There are multiple applications if we implement traffic signal metering at the roundabouts,” Baird said on Nov. 13, offering his professional opinion that adding signals to the roundabout would better enable it “to handle the huge surges in traffic,” as well as allowing the city to prioritize different kinds of traffic: “You can use the meters [sic] to ultimately give green time to transit.”
Dickey said that the new roundabout planned to connect the Forest Road extension to SR 89A would also be signalized, and “possibly” the Jordan Road roundabout as well. “This is something that we’ll look at for all of our intersections,” Dickey said.
“All of these signals would be talking to each other. The most important thing is getting a gap in the roundabouts,” Harris said. “People are encroaching into the roundabout and then creating the obstruction.”
Harris added that traffic lights in Sedona are highly prone to breakdowns in August and September due to the effect of local temperatures on the lights’ circuit boards, and that the signalization process will also involve limiting pedestrian access to the roundabout crosswalks with separate signals.
“That is kind of messing up what we’re trying to do, which is create efficiency,” Dickey said.
A three-state study by the Insurance Institute of Highway Safety found that roundabouts “contributed to an 89% reduction in delays and 56% reduction in vehicle stops” compared to signals.
“We don’t want our residents to end up behind traffic jams that are coming from the signalization that’s happening at the ‘Y,’” Councilwoman Melissa Dunn said.