"It's not going to be permanent in any way, anytime soon." Alpine Mayor Eric Green said that to the Star Valley Independent in September, before a single bollard went down at U.S. 89 and Greys River Road. He was right on schedule. The town removed the roundabout on Tuesday, Oct. 14, and the intersection went back to its usual layout the next day.
For three weeks the roundabout gathered data for a town safety plan, and the drivers who went through it were part of the test. The next step for Alpine's busiest junction happens this winter, when the Alpine Town Council sees what that data shows.
Three Weeks of Bollards on the Highway
The town's Safe Streets and Roads for All page gives the demonstration's dates as Sept. 22 through Oct. 14, 2026. The town listed what drivers would find there:
- A temporary roundabout configuration
- Pavement markings
- Plastic bollards
- Crossings
- Continued observation of traffic operations and safety
The Star Valley Independent described tubular markers and temporary curb. Green described rubber bumpers and an approach that bent traffic slightly into an S shape. Green stated the purpose plainly: "The goal is to try and slow down traffic coming through Alpine."
The dates moved before the installation went in. The September reporting and council minutes described a trial from Sept. 9 to Oct. 7. The town's later notice moved it to Sept. 22 through Oct. 14. The roundabout was only ever meant to stay for a set period, and the town ended it on the date it announced.
What the Bollards Were Measuring
Since the roundabout was a test, the useful thing to know is what it was testing. According to the Star Valley Independent's October report, the town monitored the intersection with traffic counts and camera observation. The town also named the kinds of traffic it wanted to watch go through the junction:
- Passenger vehicles
- Recreational vehicles
- Buses
- Emergency vehicles
- Pedestrians
- Bicyclists
The list fits the junction. Greys River Road runs south from this corner into the Bridger-Teton backcountry, so a design that works for a sedan also has to work for RVs and emergency vehicles. Three weeks of real traffic shows whether larger vehicles can get around the circle without trouble, and a drawing cannot show that.
The second source of data was residents. The town ran a 10-question community survey through Oct. 21. It asked where respondents live, how often they drove through the roundabout, how accessible it was, how traffic flowed compared with before, and whether they support the project and feel comfortable using a roundabout. The town said the survey also covered perceived safety, vehicle speeds, the pedestrian experience and possible future improvements. The survey has closed. Kimley-Horn, the engineering consultant on the project, will combine the responses with the traffic data.
The test was also inexpensive compared with permanent construction. Council minutes from the Sept. 1 meeting show approval of a payment of up to $25,663.03 to Idaho Traffic Safety, with the full demonstration estimated at about $44,000. The town spent that money to see how the junction works with a roundabout before deciding whether to design one.
Why This Corner Came First
The demonstration came out of a larger effort. Alpine is writing a Transportation Safety Action Plan under the federal Safe Streets and Roads for All program, and the town says the plan covers safety needs and possible improvements across Alpine. The Star Valley Independent reported in 2025 that a $60,000 grant from the Wyoming Governor's Infrastructure Matching Funds program covered the town's local match for the federal project.
The plan goes well beyond one intersection. The Star Valley Independent reported in August that Kimley-Horn's job is to assess safety in Alpine and just outside town limits, with a focus on fatal and serious injuries. The final plan is expected to describe and price possible improvements, including 12 safety-improvement projects. The same report listed both the Greys River Road intersection and the Snake River Canyon intersection among the safety concerns.
The groundwork came before the bollards. In May 2026, Kimley-Horn and town representatives did field reviews along U.S. 89, and the US 89 Road Safety Audit that followed in June recorded observations on vehicle speeds, pedestrian crossings, lighting, wildlife and intersection conditions. The town calls the audit's recommendations "options for further consideration." A Kimley-Horn presentation on the audit and the demonstration was on the council's June 23 agenda.
The traffic the plan is responding to is real. A Wyoming Department of Transportation sample counted 3,674 vehicles in both directions in one 24-hour period on July 30. That is a midsummer count, taken while the highway into the Snake River Canyon is busiest. It gives Kimley-Horn a baseline for comparing traffic during the fall demonstration.
So the Greys River junction is one of several locations in a plan that is still being written. The roundabout was the one option the town could test at full scale before the plan is finished.
A State Highway Means a Second Party at the Table
U.S. 89 is a state highway, and that affects how any change at this corner gets made. According to the Star Valley Independent's September coverage, WYDOT supported Alpine's grant application and reviewed the proposals and designs. During the demonstration, WYDOT planned its own informal monitoring, while Kimley-Horn handled the formal data collection and the review afterward.
The same report named two other Wyoming towns where WYDOT has allowed temporary traffic tests:
| Location | Temporary measure, as WYDOT described it |
|---|---|
| Sheridan | A lane reconfiguration from four lanes to three |
| Pinedale | A U.S. 191 demonstration using flexible delineators |
| Alpine | A temporary roundabout at U.S. 89 and Greys River Road |
Pinedale and Sheridan show that trying a change temporarily first is now normal practice on Wyoming state highways. For Alpine, it means the data from these three weeks will be reviewed by the town council and by the state agency that owns the road.
Where the Decision Goes From Here
The town's position hasn't changed since before the installation: "No decisions about permanent improvements have been made." According to the Star Valley Independent, Town Administrator Riley Hovorka said Kimley-Horn Engineering will present the demonstration data and the survey results at a town council meeting in November or December.
The remaining council meetings this year on the town's meetings calendar are:
- Tuesday, Nov. 17, 2026
- Tuesday, Dec. 1, 2026
- Tuesday, Dec. 15, 2026
Anyone who wants to see the numbers from the three weeks will find them at one of those meetings. The town's demonstration FAQ and the US 89 Road Safety Audit memo are posted on the town's SS4A page for anyone who wants the background first.
For now, the corner of U.S. 89 and Greys River Road has its usual layout and the bollards are gone. Whatever the town eventually does with the junction will come out of the safety plan, which also covers the Snake River Canyon intersection, and the presentation is the next step in that process.
Road decisions at the north end of Star Valley affect daily drive times, how a property is reached and, over time, what a location is worth. If you are weighing a home or land in Alpine and want to know how the safety plan could affect a specific location, Colby Murphy follows these council decisions closely and can go over them with you. Work with Colby Murphy.
