The Idaho Transportatio
n Department has collected the votes and is making plans for three new noise walls along Interstate 84 as a part of a multi-year study of improvements in Canyon County.
ITD proposed four locations for noise walls. Those locations and the results of votes from those who would benefit from them are:
- Along eastbound I-84 adjacent to the Indian Creek Estates – approved
- Along the westbound on ramp at Franklin Road – approved
- Along westbound I-84 between Centennial Way and 10th Ave. – approved
- Along eastbound I-84 between Centennial Way and 10th Ave. – not approved
ITD invites members of the community to ask questions about the project on Oct. 17 at the Caldwell Best Western (908 Specht Ave.) anytime between 4:30 p.m. and 6:30 p.m.
“The decision whether or not to build noise walls belongs to those adjacent owners and residents who are shown to be affected by future traffic noise,” said ITD Transportation Program Manager Amy Schroeder. “ITD’s role is to model the change in noise levels to determine who is a benefited receptor, follow state and federal noise policies, and facilitate the decision-making process,.”
A noise analysis was conducted earlier this year to determine the increase in traffic noise from adding a third lane in each direction on I-84. The next step was to confirm whether noise walls would reduce sound by 5 decibels or more. Human speech ranges from 50 to 65 decibels; traffic noise ranges from 70 to 80 decibels.
The noise study also identified specific properties, or “receptors” that would benefit from mitigation measures such as a wall. These property owners were invited to vote on the walls through an extensive balloting process in July and August 2019. View a map of the receptors.
For a noise wall to be approved, ITD policy states that more than 50 percent of affected property owners must vote “yes.” If the property owner vote is 50 percent or fewer, then affected residents are invited to vote. Resident votes must be greater than 75 percent to overturn the owners’ “no” vote.
The walls will be designed using concrete panels between 12 feet and 16 feet tall.
ITD is investing more than $330 million into Interstate 84 in Canyon County over the next several years. More information about the I-84 expansion is available at itdprojects.org/84corridor and on the Drive Idaho podcast (available on all podcast players).

The Idaho Transportation Department has approved construction of a interim traffic signal at the intersection of Idaho Highway 55 and Brookside Lane to accomodate the Dry Creek Ranch development.
The signal, which will be paid for by the developer Boise Hunter Homes (BHH), is the next step in the development of Dry Creek Ranch. The Department is permitting this signal for the time being to accommodate the vehicles accessing Brookside Lane currently and in the near future. As the development continues to grow, ITD is requiring BHH to construct additional improvements and remove the signal. A similar agreement is in place for the Avimor development to the north.
“ITD’s long-range vision for this section of ID-55 requires the corridor to be free of signals north of Beacon Light,” said Amy Revis, District Engineer of ITD’s Southwest Idaho offices. “We often phase implementation of improvements to meet current and near-term traffic demand, allowing the development to generate revenues which can fund the ultimate mitigation improvements.”
ITD has an agreement with BHH and Ada County that improvements to ID-55 must be constructed at certain stages of growth. This is measured by the number of trips into the development during the evening rush hour. ITD collects the trip data annually. Currently, there are 100 trips per hour.
- At 550 trips per hour, the developer must construct an additional travel lane in each direction on ID-55 from Beacon Light Road to a few hundred feet north of Brookside Ln.
- At 1300 trips per hour, the developer must remove the signal and construct an alternate intersection that allows free-flowing traffic at 55 mph.
With the approval from ITD, BHH is now cleared to construct the signal. No exact timeline for construction has been provided to the Department.
ITD collaborates with developers and local governments to find balanced solutions that achieve the Department’s mission of “Your Safety. Your Mobility. Your Economic Opportunity.”
Several intersections on Idaho 55 will be closed beginning Oct. 1. Construction crews are placing concrete gutters along the roadway. Access at each intersection’s will remain closed for 2-3 days (weather permitting) while the concrete hardens.
What to expect:
- All work will be done during daytime hours.
- Work is anticipated to take approximately two weeks to complete (weather permitting).
- Work will be conducted between Bruneau Hwy. to Edwards St. on the north; Bruneau Hwy. to 9th St. on the south.
- Side streets will be closed to all traffic while work is being done and while concrete hardens. Closures will be staggered.
- Major intersections will be reduced down to one lane, but will remain open at all times. Steel plates will be placed over the gutter work while concrete hardens.
Flaggers will assist with the gutter operations at the major intersections.
The contractor will be placing the next set of girders tonight, Oct. 1. What to expect:
- ID-55 and the Snake River Bridge will be closed for up to 30 minutes each time one of the girders are being placed.
- Sunny Slope Road southbound will be reduced to one lane between Lowell and True roads. The lanes will be restricted from noon to 2:00 am each night to stage the bridge girders.
- Work will generally be done between 10:00 pm and 2:00 am.
- The work will be noisy.
Interstate 84 will be closed overnight between the Karcher/Midland and Northside interchanges on Monday, Sept. 16 through Thursday, Sept. 19. The closures will allow crews to safely remove the wooden forms that temporarily supported the new bridge deck this summer.
- Westbound I-84 will be closed for two nights – Sept. 16 and Sept. 17. Each night I-84 will be closed from 10 p.m. to 6 a.m.
- Eastbound I-84 will be closed for two nights – Sept. 18 and Sept. 19. Each night I-84 will be closed from 10 p.m. to 5 a.m.
During the four overnight closures, motorists will exit I-84 at Karcher/Midland or Northside and follow a detour along Karcher Road. Flaggers will direct traffic. View the detour map.
Lane restrictions and flaggers will also be in place on the Northside Boulevard between the ramps each night while crews begin to work on the new bridge.
The new Karcher Overpass is on schedule to re-open later this fall. Reconstruction of the Northside Interchange has begun and will continue through early 2021.
For more information about the reconstruction of I-84 in Canyon County, visit itdprojects.org/84Corridor. To receive construction updates; text 84corridor to 555888. “Drive Idaho,” ITD’s new podcast series on all things I-84 in Canyon County, is available for download on Spotify and Apple Podcast and other major podcast sharing sites.
There will be temporary closures on Idaho Highway 55 at the Snake River Bridge in Marsing while girders are placed for the new bridge.
Girders are large horizontal beams that support the surface of the bridge. Each girder weighs 141,000 pounds and is 148 feet long. Current plans call for girders to be placed overnight on Tuesday Sept. 3, Thursday Sept. 5, Friday Sept. 13, and Monday Sept. 16. This is subject to change.
Sunny Slope Rd. southbound will be reduced to one lane between Lowell and True road. The lanes will be restricted from noon to 2:00 am each night to stage the bridge girders. Placement of the girders will generally occur between the hours of 10:00 pm and 2:00 am. Traffic will be stopped for up to thirty minutes while each girder is placed. Each night up to three girders will be placed.
This work is part of a two year-long project to replace the Snake River Bridge in Marsing The project will improve safety and driving conditions on the bridge, which is the primary river crossing for the area. More information can be found at https://itdprojects.org/marsing55improvements/.
Ahead of constructing additional lanes on Interstate 84 in Canyon County, the Idaho Transportation Department is reconfiguring westbound lanes of the Interstate near the Franklin Blvd. interchange.
Currently, three westbound lanes are reduced to two lanes with the far left lane merging into the center lane. In the new configuration, the left lane will no longer merge, remaining a travel lane. The far right lane will end, used as the off-ramp to Franklin Blvd. A similar configuration is on westbound I-84 at the Garrity Blvd. interchange, where the Interstate is reduced from four to three lanes.

“This reconfiguration maintains the existing capacity of I-84 during construction,” said ITD Project Manager Styles Salek. “With this change, we remind motorists to slow down, plan ahead and pay attention in construction zones.”
In order to promote the safety of motorists and construction crews, ITD has partnered with the Idaho State Police to provide enhanced patrols throughout the duration of the project.
This change will allow crews to begin adding lanes in the I-84 median between Karcher/Midland and Franklin Boulevard. The addition of lanes is part of the ongoing I-84 corridor project from Nampa to Caldwell. Improvements are expected to improve safety, address congestion and benefit the regional economy for many years.
For more information about the I-84, Karcher to Franklin project, listen to the Drive Idaho podcast, visit itdprojects.org/84corridor or text 555888 to request construction updates. You can also contact ITD at 84corridor@itd.idaho.gov and (208) 334-8002.
The Idaho Transportation Department has scheduled an overnight closure for the westbound I-84 off-ramp at the Karcher/Midland Interchange on Friday, July 26. The planned closure will allow crews to pave the ramp as part of ongoing improvements to widen I-84 from Nampa to Caldwell.
The off-ramp will be closed from 10 p.m. July 26 to 7 a.m. July 27. Motorists seeking access to Karcher Road or Midland Boulevard from westbound I-84 will need to use the Northside Boulevard exit and follow posted detour signs. See a map of the detours below.

Overnight closures on I-84 are part of ITD’s large-scale project geared towards improving the I-84 corridor between Nampa and Caldwell. The work is expected to improve safety, address congestion and benefit the regional economy for many years.
For more information about I-84 in Canyon County, listen to the Drive Idaho podcast or visit ITDprojects.org/84corridor. To request construction updates right to your cell phone, text 84CORRIDOR to 555888.
The Idaho Transportation Department is issuing a travel advisory on Idaho Highway 55 near Marsing for July 3, 2019.
Construction to rebuild ID-55 through downtown Marsing and the bridge over the Snake River will impact travel around the City of Marsing’s annual July 3rd Fireworks Extravaganza at Marsing Island Park. Traffic will be reduced to a single lane on the highway north of the bridge and in town. No left-turns will be allowed in town during the event.
The Snake River Bridge is closed to pedestrians and bicyclists. The City of Marsing has arranged for a free shuttle service to and from the event. Please see the event map below for details.

ITD encourages those planning to attend the event consider using U.S. 95 to reach Marsing. Consider carpooling to alleviate congestion as over 5,000 visitors are expected to arrive for the celebration. Plan extra time for the return trip. Please exercise patience and kindness as you leave.
ITD reminds those who will be drinking during the event to make a plan in advance to get home safe. The Department is partnering with law enforcement to increase DUI patrols during the Fourth of July week.
Following a speed study of I-84 in the urbanized parts of the Treasure Valley, the Idaho Transportation Department (ITD) is reducing the speed limit on the western side of Caldwell to 65 MPH.
The current speed limit on I-84 traveling west goes from 65 MPH to 80 MPH after the Notus/Parma Exit (Exit 26). Due to the high number of vehicles using Middleton Exit (Exit 25) both east- and westbound coupled with varying speeds of thru traffic and merging vehicles, the Department determined a speed reduction was warranted. The 65 MPH speed zone will now extend west of Exit 25. Crews will place new speed limit signs today.
“We observed significant variations in speeds, with entering traffic speeding up to merge with I-84 traffic, which was slowing for the speed limit change,” said ITD Traffic Technical Engineer Erika Bowen. “This resulted in a number of near misses between cars on the Interstate and those looking to enter. Given the high demand at the Middleton Exit, we believe the change will improve the driving conditions in this area.”
ITD routinely studies sections of the State Highways System to ensure the safety, mobility, and economic opportunity of the traveling public is best served. Staff looks at the pavement condition, crash history, geometry, signage, and observed driver behavior when considering changes to the highway.
Over the last five years, growth near the Middleton Exit has seen an increase of 5,000 vehicles per day added to this section of I-84. During the evening commute, congestion often occurs at Exit 25 causing backups on the westbound off-ramps. ITD is looking at solutions for this separate situation to improve the efficiency of the interchange.
UPDATE (June 11)
I-84 detours in Nampa have been extended due to equipment-related delays during the Karcher Overpass girder placement. A detour will be in place Tuesday and Wednesday nights (June 11 and 12) between the Karcher/Midland and Northside Boulevard interchanges.
- Eastbound I-84 will be closed overnight Tuesday, June 11. A detour will begin at 10 p.m. Tuesday and end at 5 a.m. Wednesday, June 12.
- Westbound I-84 will be closed overnight Wednesday, June 12. A detour will begin at 10 p.m. Wednesday and end at 6 a.m. Thursday, June 13.
Original Story (June 4)
ITD will require overnight closures on Interstate 84 in Nampa next Tuesday and Wednesday nights (June 10 and 11) to place girders on the new Karcher Road Overpass.
- Eastbound I-84 will be closed overnight Monday, June 10. A detour will begin at 10 p.m. Monday and end at 5 a.m. Tuesday, June 11.
- Westbound I-84 will be closed overnight Tuesday, June 11. A detour will begin at 10 p.m. Tuesday and end at 6 a.m. Wednesday, June 12.
Motorists will follow a detour route on Karcher Road both nights. See detour map below.

“ITD will place 10 steel girders over the two nights. Each girder is 136 feet long and weighs approximately 115,670 pounds,” said Alex Deduck, ITD Design/Construction Engineer. “This is no small operation and we appreciate the patience of the traveling public during the detour.”
ITD is replacing the Karcher Overpass to accommodate additional lanes on I-84. Construction to widen I-84 will begin later this summer.
For more information, visit itdprojects.org/84Corridor, text 84CORRIDOR to 22828 or listen to “Drive Idaho,” ITD’s new podcast series on I-84. Drive Idaho is available on Apple Podcasts, Spotify and other major podcast players.