City of Pocatello to Begin Portneuf River Bridge Replacement Construction in Mid-April
State Grant Fully Funds West Benton Street Bridge Replacement in Pocatello, Idaho
POCATELLO, Idaho — The City of Pocatello is set to begin construction on the Portneuf River Bridge on West Benton Street in mid-April, officials announced, with the project aimed at replacing an aging steel girder structure with a modern, single-span concrete girder bridge designed for improved safety and long-term durability.
The project is being funded entirely through the Leading Idaho Local Bridge (LILB) Grant, administered by the Local Highway Technical Assistance Council. The grant requires no local match from the City of Pocatello — a significant fiscal benefit for city taxpayers who will see infrastructure improvements without additional burden on municipal funds.
The LILB Program was established by the Idaho Legislature through Senate Bill 1359 and is designed to support the repair or replacement of bridges greater than 20 feet in length that are in poor condition or have load restrictions, in accordance with Federal Highway Administration guidance. The program represents a targeted, results-oriented approach to infrastructure investment, directing state resources toward structures with documented deficiencies rather than broad, unfocused government spending.
What the Construction Project Involves
The replacement bridge will feature a deep foundation system using driven piles, providing structural stability suited to the conditions along the Portneuf River corridor. The new single-span concrete girder design is intended to offer greater long-term reliability compared to the existing steel girder configuration currently in place.
In addition to the bridge structure itself, the project scope includes reconstruction of roadway and pedestrian approaches on both sides of the bridge, as well as the relocation of select utilities in the construction zone. All work will be completed in accordance with the 2023 Idaho Standard Specifications for Highway Construction, ensuring the project meets current engineering and safety standards.
The Portneuf River runs through the heart of Pocatello, and the West Benton Street crossing serves as an important local route. Replacing the deteriorating structure will restore full load capacity and eliminate restrictions that can complicate traffic flow for both personal vehicles and commercial use.
This project is one of several infrastructure improvements underway in Pocatello this spring. The city is also moving forward with two major road safety projects launching in April, reflecting a broader push by local officials to address deferred maintenance and upgrade aging transportation infrastructure throughout Bannock County.
Road Closure and Timeline for Pocatello Drivers
Residents and commuters in the area should be prepared for a temporary road closure on West Benton Street at the Portneuf River crossing for the duration of the construction period. City officials are encouraging all travelers to exercise caution and plan for alternate routes while work is underway.
Construction is anticipated to be completed by the end of September 2026, weather and other unforeseen conditions permitting. The roughly five-month construction window reflects the scope of work involved in a full bridge replacement, including foundation work, structural installation, and approach reconstruction.
For a project of this scale, the full grant funding through the LILB Program means Pocatello taxpayers will receive a modernized and safer river crossing without reaching into city coffers for a local match — an outcome that reflects the kind of efficient, targeted infrastructure funding model that serves communities well. The Idaho Legislature’s creation of the LILB Program has enabled municipalities across Southeast Idaho and the rest of the state to address bridge deficiencies that might otherwise go unresolved due to local budget constraints.
Drivers in the West Benton Street area are advised to monitor City of Pocatello communications for updates on the closure schedule and recommended detour routes as construction begins.
What Comes Next
Construction is expected to begin in mid-April 2026 and run through the end of September, barring weather delays or other unforeseen complications. City officials have not yet released specific detour route information, but residents are encouraged to follow city announcements as the project gets underway. For broader coverage of Idaho infrastructure and transportation policy, visit Idaho News and the Idaho News Network.