US-12 emergency rock scaling project starts today to reduce likelihood of rockfall

Picture taken from a drone on a cloudy day above US-12 and overlooking the rocky slope by Arrow Bridge.

SATURDAY, NOVEMBER 22 UPDATE:

U.S. Highway 12 near Arrow Bridge has re-opened one lane this evening with flaggers allowing a single, alternating lane of traffic to pass through the work zone through the night. Drivers should plan for delays of up to 20 minutes.

This is a dynamic project, with conditions that may change quickly so ITD encourages the public to use Idaho 511 for the most up-to-date traffic and closure information. Travelers can visit the website at 511.idaho.gov, dial 5-1-1 or download the Idaho 511 app on any smart device.

FRIDAY, NOVEMBER 21 UPDATE:

All lanes of U.S. Highway 12 near Arrow Bridge will temporarily re-open to traffic starting at 5:30 p.m. tonight until 8:00 a.m. tomorrow morning. Crews have made significant progress on the slope above US-12 and engineers have deemed it safe to open for traffic through the night.

Drivers should expect flaggers throughout the area to monitor traffic and the slope for safety.

Work will start again tomorrow morning, closing US-12 at 8:00 a.m. If all goes as planned, ITD aims to reopen the highway at 5:00 p.m. tomorrow evening. Idaho 511 is the best resource for drivers with updated traffic conditions, detour routes and closure information.

Please use caution through the area and be aware of the possibility of debris in the roadway as work continues to clear the slope of loose rocks through the weekend.

Up-to-date traffic information and the latest schedule for this project can be found by visiting 511.idaho.gov. Travelers can also dial 5-1-1 or download the Idaho 511 app on any smart device.

THURSDAY, NOVEMBER 20 UPDATE:

All lanes on U.S. Highway 12 near Arrow Bridge will close tomorrow at noon for rock scaling. Crews will proactively dislodge large rocky sections from the nearby slope under controlled conditions which decreases the likelihood of future rockfalls that create a safety hazard for drivers. Traffic will be detoured to alternative state routes on U.S. Highway 95, State Highway 3, State Highway 13, and State Highway 162.

The closure will stay in place around the clock until crews finish removing unstable rock. Because conditions on the slope can vary, a specific reopening time can’t be set in advance. Drivers should plan for an extended closure. However, if work progresses smoothly, the closure is not expected to last more than a day or two. At this time, we do not expect this closure to impact the Thanksgiving holiday.

“The decision to close the highway was made from a safety standpoint to protect travelers from falling rocks and to allow for a timelier cleanup process,” Operations and Traffic Engineering Manager Jared Hopkins said. “Heavy equipment will load trucks with the freshly fallen rocks and those will be hauled offsite.”

In addition, there will be increased truck activity outside of the work zone. Trucks will frequently be entering and exiting the highway on US-12 by Cherry Lane Bridge and near the south end of Arrow Bridge.

Experts have been monitoring the slope since Tuesday to ensure there is no danger to drivers and flaggers have been providing traffic control. Motorists should also pay close attention to road signs posted in the area.

Up-to-date traffic information can be found by visiting 511.idaho.gov. Travelers can also dial 511 or download the Idaho 511 app.

WEDNESDAY, NOVEMBER 19 UPDATE:

Rock scaling crews arrived on site today in preparation for the US-12 emergency roadside project near Arrow Bridge. The slope was evaluated and will be prepped for scaling.

Anchor points will be installed so that workers can climb the slope with their equipment. It is anticipated that the rock removal will begin on Friday.

While rocks are dislodged, flaggers will stop traffic at a safe distance. Delays will be 20 minutes at a time. If conditions change, a full closure may be implemented for safety.

Up-to-date traffic information can be found by visiting 511.idaho.gov. Travelers can also dial 5-1-1 or download the Idaho 511 app.

TUESDAY, NOVEMBER 18 UPDATE:

The Idaho Transportation Department is conducting rock scaling work to stabilize the slope above U.S. Highway 12 near Arrow Bridge between mileposts 15 and 16. This effort began today and is expected to continue through the middle of next week. Work will intermittently affect traffic.

Scaling involves wedging and prying debris loose proactively, with rocks falling from the hillside down to the road. Specialized equipment will excavate rock at the top and flatten the slope.

“We are taking a proactive approach by dislodging any unstable material with professional scalers in a controlled setting,” Operations and Traffic Engineering Manager Jared Hopkins said. “For the safety of the traveling public, we’ll have flaggers there to monitor the slope and stop traffic while workers are scaling.”

An anticipated work schedule is as follows and is subject to change based on conditions:

Tue., Nov. 18 – Thu., Nov 20: Flagging operations with 20-minute delays.
Fri., Nov. 21 – Sun., Nov. 23: Full closure potentially all day and overnight. Motorists will be detoured to alternative route on State Highway 13 or State Highway 162.
Mon., Nov. 24 – Wed., Nov. 26: Flagging operations with 20-minute delays until work concludes.

“If the slope becomes too unstable, an extended closure may be needed and drivers will be detoured to State Highway 13 or State Highway 162 in that case,” Hopkins said. “As work continues, we may allow traffic to flow without being stopped during work if it is safe to do so.”

Up-to-date traffic information can be found by visiting 511.idaho.gov. Travelers can also dial 5-1-1 or download the Idaho 511 app.

SH-55 closed between Florida Ave and Lake Ave this weekend

Aerial view of a roadway under construction running through farmland and developed areas, with vehicles traveling on the open lanes and work zones marked by orange fencing on both sides of the corridor.

The Idaho Transportation Department will close State Highway 55 (Karcher Road) between Florida Avenue and Lake Avenue from Friday at 10 p.m. until Monday at 5 a.m.

This will allow crews to replace an irrigation pipe just east of the SH-55 and Florida Avenue intersection, which must be completed before paving the roadway.

Highway traffic is encouraged to detour around the closure using Interstate 84, State Highway 19 and U.S. 95. To view a map of the closure location and detour visit the project website at itdprojects.idaho.gov/pages/55farmway

This work is a part of the larger SH-55 project occurring between Farmway Road and Middleton Road to improve safety and mobility along the SH-55 Corridor in Canyon County. Construction is expected to be finished in fall 2027.

For more information about the SH-55 Farmway to Middleton widening project, please visit itdprojects.idaho.gov/pages/55farmway, call 208-477-1379, or email info@55farmwaytomiddleton.org.

To receive text alerts about these weekend closures, text 55FARMWAY to 866-483-8422.

Nighttime closures Monday and Tuesday at the Karcher Interchange Bridge

Aerial view of traffic traveling across a bridge on State Highway 55 in Nampa, passing under overhead signs for I-84 west to Caldwell and Ontario, Midland Boulevard north, and the Karcher Bypass.

The Idaho Transportation Department will close the Karcher Overpass Bridge on Monday, and Tuesday from 10 p.m. to 5 a.m each night. Crews will be removing the large steel structure that holds the signs over the bridge to make room for new signs that will support the new lane configuration.

Detours signs will be posted for drivers during the closures.

Motorists traveling south on Karcher Road (State Highway 55):

Travel south on the Karcher Bypass.
Turn right onto West Karcher Road.
Turn left onto Midland Boulevard.
Turn right onto Caldwell Boulevard.
Continue straight to Karcher Road (SH-55).

Motorists traveling north on Karcher Road (SH-55):

Use the eastbound on-ramp to merge on to Interstate-84.
Exit I-84 at Northside Boulevard (Exit 35).
Travel north on Northside Boulevard.
Turn left onto Karcher Road/Karcher Bypass.
Continue on Karcher Road/Karcher Bypass.

Click here to view the detour map.

The I-84, Karcher Interchange project will improve safety and mobility at the interchange and along Karcher Road in Nampa. Crews are expected to place final touches in late spring of 2026.

Stay informed by signing up for email and text alerts regarding project updates by texting 84CORRIDOR to 1-866-483-8422 or visit the project page at itdprojects.idaho.gov/pages/karcheric.

ITD begins 2 week project to resurface the Flying Wye

Starting Monday the Idaho Transportation Department will begin a two-week project to micro mill and re-paint the Flying Wye connector linking Interstate 84 and Interstate 184.

This work will take place in two phases:

Phase 1: Nighttime micro milling

Between 10 p.m. and 5 a.m. crews will remove the top layer of pavement overnight to reduce impact on daytime traffic. Drivers should expect lane reductions each night during this phase.

Phase 2: Daytime striping

Striping will then occur during the day when warmer temperatures are required for the paint to adhere to the roadway properly. Lane closures will continue as crews install new markings across the bridge.

Motorists are encouraged to plan for additional travel time and check 511.idaho.gov or the Idaho 511 mobile app for the most current traffic impacts, lane closures and travel conditions throughout the project.

Northbound I-15 traffic between the Northgate and Fort Hall interchanges shifts this week

I-15 with construction being conducted on the new lanes between northbound and southbound lanes.

The Idaho Transportation Department will shift northbound Interstate 15 traffic between the Northgate and Fort Hall interchanges (Exits 73 and 80) the night of Wednesday, Nov. 12. Northbound traffic will move into the newly constructed lanes in the median to allow crews to begin work on the east side of I-15.

During the traffic shift, motorists can expect:

The northbound on-ramp at the Northgate Interchange (Exit 173) will close for a few hours on Wednesday night, Nov. 12.
Lane closures may occur in the project area.

After traffic is shifted, motorists can expect:

Two lanes will remain open in each direction on I-15 during the daytime.
A concrete barrier will separate opposing lanes of traffic.
Reduced speeds in the work zone.

Once the new northbound lanes are completed in late 2026, crews will complete the southbound lanes on the west side of I-15. Construction on the I-15 Northgate to Fort Hall widening project is anticipated to be completed in 2027. This project is funded by Governor Little’s Leading Idaho initiative and will result in three lanes in each direction on I-15.

For more information and to sign up for email or text updates visit itdprojects.idaho.gov/pages/i15northgatetoblackfoot or call 208-252-5553.

The safety of motorists and construction crews is ITD’s top priority during construction. When driving through the work zone, please stay alert, follow work zone signage and drive the posted speed limit. Drivers are encouraged to plan extra time when traveling through the project area and check 511.idaho.gov or the 511 mobile app for the latest updates on restrictions and delays.

Culvert repairs begin Nov. 13 on SH-45 in Nampa

View looking down a busy commercial street with cars driving in both directions. A sidewalk runs alongside the road with fall-colored trees. Visible businesses include Arby’s on the left and Subway on the right. The sky is clear and blue.

The Idaho Transportation Department will begin roadside work Nov. 13 to repair the Elijah Drain culvert beneath State Highway 45 (12th Avenue) near West Dewey Avenue.

SH-45 will remain open throughout construction. Traffic impacts are not expected until mid-December when crews start working along the shoulder. Drivers should expect short lane shifts or brief flagging operations as needed. Most traffic impacts will occur at night to reduce delays for daytime travelers.

Nearby businesses will remain open and accessible during construction, and no driveway closures are planned.

The work will protect the roadway structure and ensure SH-45 continues to serve the growing Nampa community safely. Construction is expected to continue through spring 2026.

Drivers should watch for crews and equipment, obey posted signs, and slow down when traveling through the work zone.

For real-time traffic updates, visit 511.idaho.gov or use the Idaho 511 mobile app.

New digital sign on SH-55 to improve communication

Graphic showing a State Highway 55 road sign with a white background and black outline. The sign reads “Idaho 55” with the state shape and shield design typical of Idaho highway markers.

Drivers on State Highway 55 should expect short delays Wednesday as the Idaho Transportation Department installs a new digital message sign in Round Valley.

A crane will be on site beginning at 10 a.m. and continuing through the afternoon to set the overhead sign structure at milepost 102 just south of Cascade near the descent toward Rainbow Bridge.

During installation, crews will reduce SH-55 to a single lane with alternating traffic. A full closure of up to 15 minutes may be needed while the structure is lifted into place to keep travelers safe from the suspended load.

The new sign will make SH-55 safer by providing real-time alerts about wildfires, delays, and other emergencies along one of Idaho’s busiest mountain corridors. Limited cell service in the canyon makes roadside communication especially valuable for drivers. Drivers can expect the sign to be operational by the end of the year.

Motorists should slow down, follow flagger directions, and watch for crews and equipment in the area.

For the latest updates on traffic impacts and road conditions, visit 511.idaho.gov or download the Idaho 511 app.

Nighttime closures begin this weekend on Franklin Road near I-84

Aerial view of a large highway construction project cutting through open farmland. The image shows a major intersection where crews are building an overpass or interchange, with heavy equipment, cranes, and dirt embankments visible on both sides. Traffic cones line the crossroad, and nearby fields and a few buildings stretch into the distance under a clear blue sky.

The Idaho Transportation Department advises motorists to prepare for nighttime closures over the next month on Franklin Road between Star and McDermott roads as crews place eight steel girders for the future State Highway 16 and Franklin Road Interchange. The girders are horizontal support beams for the bridge, estimated to weigh approximately 184,000 pounds each and will be installed in parts throughout the month of November.

Motorists can expect:

Franklin Road will be closed at night from 8 p.m. to 8 a.m. from Star to McDermott roads.
Closures will begin Saturday, Nov. 8, and will take place throughout the month.
Traffic will be detoured to Cherry Lane.

When complete, the Franklin Road Interchange will allow through traffic on SH-16 to travel over Franklin Road without stopping. The SH-16 and Franklin Road Interchange is expected to open with the entire SH-16 corridor in 2027.

For more information and to sign up for email or text updates visit itdprojects.idaho.gov/pages/sh16corridor or call 208-334-8008.

Drivers are encouraged to plan extra time when traveling through the area at night and check 511.idaho.gov or the 511 mobile app for the latest updates on restrictions and delays.

SH-16 to fully close this weekend between SH-44 and US-20/26

Aerial view of an active highway construction site with multiple excavators, loaders, and work trucks operating on a large dirt area. Crews wearing safety vests work near a newly installed concrete box culvert. Construction materials, trailers, and equipment are scattered around the site. In the background, vehicles travel along a nearby highway, and autumn-colored trees and residential buildings border the work zone under clear blue skies.

State Highway 16 will be fully closed south of State Highway 44 the weekend of Nov. 7-10 as the Idaho Transportation Department installs a drainage structure underneath the highway. SH-16 will be closed between SH-44 and US-20/26. Traffic will be detoured to Star and Linder Roads.

Closures will begin at 9 p.m. Nov. 7 and will end at 5 a.m. Nov. 10. Work will result in significant noise during this time.

Crews will install a drainage structure, also called a box culvert, underneath SH-16. The structure will be 495 feet long and comprised of 86 individual pieces, each measuring 8 feet wide by 6 feet tall and weighing an average of 22,500 pounds.

The culvert is being installed as part of the work on the future SH-16/SH-44 Interchange, which will connect SH-16 to Interstate 84. The new SH-16 corridor is on track to open in 2027.

Motorists are encouraged to text HIGHWAY16 to 1-866-483-8422 for email or text alerts. For maps and details about the project, please visit itdprojects.idaho.gov/pages/sh16corridor.

I-90 striping work to impact eastbound traffic on Sunday

COEUR D’ALENE – Drivers should plan for delays this Sunday on eastbound Interstate 90 between Post Falls and Coeur d’Alene as crews complete striping in the work zone to expand the freeway to four lanes. Work will begin around 7 a.m., with traffic reduced to one lane and the speed limit lowered to 45 mph throughout the day.

“This is one of the last weather-dependent tasks we have to complete before winter, and this weekend just might be our last chance to do it with the conditions needed,” Project Manager Tom Trutter said. “We’re doing it Sunday when traffic is lighter, but congestion is still expected so we’re asking drivers to plan extra time and be patient through the work zone.”

Due to the temperatures needed for the paint to dry properly, this work cannot be done overnight.

In addition to this work, new variable speed limit signs will soon be activated along the I-90 corridor during the expansion project. These digital signs allow ITD to adjust posted speeds for safety when crews are working close to traffic. As a reminder, drivers are required to follow the posted speed limit at all times and should not rely on in-car navigation systems or GPS devices through the work zone, as they may differ from the posted speed.

This five-mile stretch of I- 90 from State Highway 41 to U.S. Highway 95 is the most heavily traveled and congested area in the corridor. This is the first construction project to advance from the I-90 Corridor Study from SH-41 to 15th Street to enhance safety and add capacity to support future traffic volumes.

Construction began in August of 2025 and is expected to be complete in 2029.

To stay informed about project updates, impacts and milestones, drivers can sign up for email and text updates at I-90 Widening: SH-41 to US-95 | ITD Projects.