Southbound SH-75 will detour to 2nd Avenue beginning Aug. 17
Southbound SH-75 traffic will detour to 2nd Avenue beginning Monday, Aug. 17. The detour will allow Idaho Power and Intermountain Gas Company to perform utility work in the area.
Overview
Crews are constructing improvements to SH-75 between Elkhorn Road and River Street in Ketchum.
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Elkhorn Road is OPEN!
Elkhorn Road is open between SH-75 and Weyyakin Drive!
The traffic signal at the intersection of SH-75 and Elkhorn Road has been reactivated. Motorists can continue to expect intermittent traffic shifts, flagging and lane closures on SH-75 and local roads.
During the closure, crews:
- Removed the roadway surface and layers of roadway material.
- Placed structural fill material in the SH-75/Elkhorn Road intersection and along Elkhorn Road.
- Installed curb and gutter along SH-75 and Elkhorn Road.
- Built sidewalk along SH-75 and installed pedestrian railings.
- Built and paved driveway approaches connecting to Elkhorn Road.
- Completed work on storm and sewer systems.
- Paved and striped Elkhorn Road and the SH-75/Elkhorn Road intersection.
Work continues on the Trail Creek Bridge
Crews will continue work on and around the Trail Creek Bridge. Please slow down, pay attention to signage and stay alert for crews in the area.
Motorists can expect:
- Work will occur during the daytime.
- Traffic shifts, flagging & lane closures will occur on SH-75 and local roads. One lane will remain open in each direction on SH-75 between Elkhorn Road and Serenade Lane.
- Short-term closures may occur on SH-75 between Serenade Lane and River Street. Residential & business access will remain open.
- Speed limits are reduced to 25 mph.
In 2026, crews will:
- Complete improvements to the intersection of SH-75 and Elkhorn Road.
- Complete improvements to SH-75 between Elkhorn Road and Weyyakin Drive.
- Widen SH-75 between Weyyakin Drive and River Street.
- Construct improvements to the intersection of SH-75 and Serenade Lane.
Work hours
Work hours have been extended to complete the Elkhorn Road to River Street project as safely and quickly as possible. This change was made with the approval of the cities of Ketchum and Sun Valley.
Work is expected to occur:
- Monday-Friday from 6 a.m.-10 p.m.
- Saturdays from 7:30 a.m.-7 p.m.
- Sundays from 8 a.m.-7 p.m.
Improvements
ITD is constructing several improvements to SH-75 between Elkhorn Road and River Street. These improvements include:
- Widening SH-75 to five lanes between Elkhorn Road and Serenade Lane.
- Widening SH-75 to three lanes with bike lanes and sidewalks between Serenade Lane and River Street, including on the Trail Creek Bridge.
- Upgrading the traffic signal at the SH-75/Elkhorn Road intersection.
- Installing a traffic signal at the SH-75/Serenade Lane intersection.
- Improving some local roads, including Serenade Lane and Elkhorn Road.
- View detailed improvement plans.
Process & Schedule
-
Spring 2025 – Summer 2025
Crews constructed:
- The northbound lanes of SH-75 from south of Elkhorn Road to Serenade Lane.
- Utility relocations and retaining walls between Serenade Lane and River Street.
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Summer 2025 – Late 2025
Crews constructed:
- The southbound lanes of SH-75 from south of Elkhorn Road to Serenade Lane.
- The northbound side of the Trail Creek Bridge.
- Utility relocations and retaining walls between Serenade Lane and River Street.
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2026 – 2027
Crews will construct:
- SH-75 between Neil’s Way and River Street.
- The southbound side of the Trail Creek Bridge.
- Improvements to the intersection of SH-75 and Elkhorn Road.
- Improvements to the intersection of SH-75 and Serenade Lane.
Crews will also complete improvements to SH-75 between Elkhorn Road and Neil’s Way.
Impacts to Local Roads
A short-term closure occurred on Weyyakin Drive where it intersects with SH-75 in 2025. The project team does not anticipate additional traffic impacts on Weyyakin Drive.
Crews plan to maintain access to Lane’s Way during construction.
The sidewalk on the east side of SH-75 closed between Lane’s Way and Elkhorn Road in 2025.
Elkhorn Road may be reduced to one lane in each direction with traffic shifts through 2026 near where it intersects with SH-75. The roadway may be intermittently reduced to one lane with flaggers directing traffic.
The sidewalk on the east side of SH-75 closed between Lane’s Way and Elkhorn Road in 2025.
River Street will be reduced to one lane heading westbound between SH-75 and Washington Avenue for several weeks in 2026.
A short-term closure will occur at the intersection of Gem Street and SH-75 in 2026. Traffic will be detoured to Leadville Avenue and River Street.
Left turns will be temporarily restricted for motorists turning onto or off Serenade Lane at SH-75 in 2026.
A short-term closure will occur on Serenade Lane between summer and late fall of 2026. The closure will occur at the SH-75/Serenade Lane intersection. Traffic will be detoured to SH-75, River Street and 2nd Avenue.
Stay informed
To stay informed about the SH-75 Elkhorn Road to River Street project and sign up for updates:
- Sign up
- Email: info@sh75project.com
- Call: (208) 254-0421
Frequently Asked Questions
In 2008, ITD published the SH-75 Timmerman to Ketchum Environmental Impact Statement and Record of Decision, which documented a study of SH-75 between the Timmerman Junction (at US-20) and Ketchum. The outcomes of the 2008 Environmental Impact Statement were re-evaluated between 2019-2024. During this process, ITD used traffic projections, safety data, community input and more to confirm final improvements.
ITD developed project plans to improve safety and increase capacity in order to accommodate traffic projections for the next 20 years.
- SH-75 will be reduced to one lane in each direction from south of Elkhorn Road to River Street.
- The Trail Creek Bridge will be reduced to one lane heading northbound for several weeks.
- Short-term impacts will occur on local roads.
- Traffic patterns may change at the intersection of SH-75 and Elkhorn Road and the intersection of SH-75 and Serenade Lane.
- Pedestrian access will be limited between Andora Lane and River Street as well as on the Trail Creek Bridge in 2026.
- The Sun Valley Pathway will remain open during construction.
- The New Spur Trail is scheduled to close for a few weeks in 2026.
No, this project does not include improvements to the River Street intersection.
Project Area Photos
