WYDOT aims for new Snake bridge in 2023
A four-lane bridge will span the Snake River on Highway 22 in just a few years.
At a public meeting last week the Wyoming Department of Transportation unveiled plans to rebuild the bridge — as well as the nearby intersection of Highways 22 and 390 — in 2023. The new bridge is planned to include four lanes, a median and standard shoulders, engineers said.
“We want to have a four-lane road,” resident engineer Bob Hammond said, “because, well, there’s a lot of traffic out there. You see it every day.”
In August 2018 WYDOT counted an average of 22,086 vehicles a day on Highway 22 west of Jackson, up from 21,330 the year before.
While the highway work will initially focus on the bridge, the widening has implications for the entire highway corridor that runs from the town of Jackson to the Idaho border, District Engineer Keith Compton said.
“It’s a smaller project of a much larger corridor at some point that we’ve got to address,” he said.
“There’s no way we could go in there and spend that kind of money to completely redo the whole corridor,” Compton said. “How do we start biting off little pieces of this?”
A first little piece, for example, was summer 2017’s tweaks to the “Y” intersection at Broadway and Highway 22.
Vague plans for the corridor have already been envisioned in a 2014 Planning and Environmental Linkage study. The PEL study recommended a four-lane highway with a median from town to the turnoff to Teton Village.
Based on that recommendation, Teton County’s 2012 comprehensive plan and 2015 Integrated Transportation Plan also call for multilane Highway 22 designed with a variety of users in mind, and for exploring high-occupancy vehicle lanes or bus lanes. WYDOT has hired a consultant to look into transit options for Highway 22, engineers said.
Compton said the Snake River bridge replacement ranks above all others across the state because the deck is crumbling and nearing the end of its life. Its narrowness and traffic volume also make it difficult to perform maintenance or handle accidents.
“If you’ve got a wreck on the structure or something like that, it completely isolates the West Bank from an emergency response perspective,” Compton said. “That’s not good.”
WYDOT’s analysis is that the best design of the new intersection at Highways 22 and 390 is something called a “Florida T.” That means widening the main roadway to four lanes while also providing a couple of “slip” lanes for vehicles that don’t have to stop at the intersection.
One slip lane will direct eastbound through traffic on Highway 22 around the intersection, while the other will allow westbound Highway 22 drivers to turn right onto Highway 390 without stopping.
“The slip lanes help traffic move on those turning movements,” Hammond said. “The lanes help for capacity. There’s also the fact that compared to some of the other choices, it had less impacts into the wetlands and surrounding areas. It has a smaller footprint.”
Rejected intersection designs included a roundabout (can’t handle the traffic volume), additional lanes (won’t work long-term) or flyovers (too expensive).
Engineers are also continuing to work with local citizens and agencies, including the Wyoming Game and Fish Department, on installing up to four wildlife crossings in the area, which is a hot spot for moose-vehicle collisions.
While the design choices are “fairly firm,” WYDOT is open to public comments, and wants to know if the agency “missed something,” Hammond said. Compton echoed a commitment to involving the public.
“We’re going to be transparent in this process,” Compton said. “We’re going to be accountable in this process. We’re going to continue to reach out and try to get information. It’s our responsibility to respond to your concerns and to not operate in a box.”