JACKSON HOLE, WYO – Options for a fix on Cattleman’s Bridge over the Gros Ventre River on Spring Gulch Road are being assessed by the Teton County Engineering Department. Specifically, engineers are trying to determine whether a temporary solution can be put in place before the bridge undergoes a scheduled, permanent replacement.
Traffic in and out of Jackson from the north has been noticeably affected by the loss of a popular ‘locals’ cutoff when the bridge failed early in June.
Currently, the WYDOT-designed Cattleman’s Bridge Replacement Project, scheduled to bid in November 2017 and open late summer of 2018, contemplates the installation of a temporary bypass during the construction of the new bridge. That temporary bridge might be necessary right now. Spring Gulch Road could reopen prior to the bridge replacement project if a temporary solution can be worked out.
Abnormally high flows in early June generated scour around several of the bridge piers. In combination with tree debris lodged against the bridge, this scour caused or exposed structural weaknesses in the bridge. On Thursday, June 8, when the bridge deck subsided approximately two feet and shifted six inches downstream, Teton County Public Works personnel closed the bridge. Since then, Public Works has been monitoring the situation daily, as well as employing contractors to remove large debris from the upstream side of the bridge to minimize additional damage.
Public Works is consulting with bridge contractors and structural engineers to assess the structural integrity of Cattleman’s Bridge and evaluate options for repair. Although water levels are almost 300% of normal for this time of year, contractors are redirecting the river flow to allow access to the damaged piers.
Teton County Public Works is coordinating this effort with WYDOT, the Federal Emergency Management Agency (FEMA), Wyoming Office of Homeland Security, and the US Army Corps of Engineers. WYDOT is the lead agency on the Cattleman’s Bridge Replacement Project and, at Teton County’s request, will attempt to accelerate the bid process to earlier this fall. However, even with an accelerated bidding and construction schedule, permanent replacement of the bridge is limited by various constraints, including but not limited to the 5 to 6 months required for ordering, fabricating, and receiving steel for the bridge. In addition, Army Corps of Engineers natural resource regulations prohibit any work in the river from March 15th to July 31st to protect spawning trout.
“Our goal is to provide connectivity as soon as possible for as long as possible, until a permanent solution is in place,” said Sean O’Malley, director of Public Works. “As we assess our options, project costs and convenience for residents and visitors are very important factors, but safety is our highest priority.”