We are working to rehabilitate three bridges along the Glenn Highway: the northbound and southbound Knik River bridges, just south of the Glenn/Parks interchange, and the northbound Peters Creek bridge near Chugiak. All three of these bridges are over 30 years old, and two are almost 60 years old (the northbound Knik River bridge and northbound Peters Creek Bridge were both constructed in the 1960s). The bridges have potholes, ruts, and other maintenance issues that need to be repaired. The purpose of this work is to extend the service lives of the bridges, reduce maintenance costs, and enhance safety.
Work on this project will include the following:
Repairing potholes in the concrete decks
Installing polyester concrete overlay to waterproof the bridges and reduce corrosion
Replacing the approach slabs to improve the driving surface
Replacing the expansion joints, damaged drainage hardware, and guardrail as needed
Upgrading signs and pavement markings
Working on utilities as needed
Timeline
2024 – Crews constructed temporary detours at the Knik River Bridges.
2025 – Work on the Knik River Bridges is expected to be complete by the end of the summer. Crews started preliminary work at the Peters Creek Bridge in July.
2026 – We expect to close the northbound Peters Creek Bridge for 45 days and reopen it before Memorial Day. Final work applying the polyester concrete overlay will be finished once the bridge is open.
Remaining 2025 Construction Impacts
Crews will resume final work at the Knik River Bridges after the Alaska State Fair is over. We will be repaving the short stretch of highway on either side of the bridges. We anticipate that this will help smooth out the approach. During this work expect changing traffic patterns and lane restrictions. Check 511.alaska.gov for the most current traffic impacts.
Figure 1. An aerial photo of the Knik River bridges. Photo credit Jonathan Tymick, DOT&PF.
2025 WORK AT KNIK RIVER BRIDGES
We closed each Knik River bridge for 30 days while we rehabilitated them. The first bridge closed in late April, and the second bridge was closed in June. When one bridge was closed the other remained open at a reduced speed limit to three lanes of traffic, two in one direction and one in the other. There were two lanes of southbound traffic open during the morning rush to Anchorage. Crews then shifted the median with the Road Zipper and opened two lanes of northbound traffic during the afternoon rush back to the Mat-Su Valley. On Saturdays there were two lanes headed to the Mat-Su Valley and on Sundays there were two lanes headed to Anchorage. Once both bridges are reopened crews will apply a final polyester concrete overlay and remove the temporary detours.
2025/2026 WORK AT PETERS CREEK BRIDGE
Crews constructed temporary detours at the Peters Creek Bridge in July 2025. This work was in preparation for the substantial bridge work in 2026. The northbound Peters Creek Bridge will close for 45 days in the spring of 2026. During this time, all traffic will be on the open bridge, and we will employ the same alternating lane technique described above that we used on the Knik River Bridges. After the bridge reopens crews will apply the final polyester concrete overlay.
Spring 2026 – The northbound Peters Creek Bridge will be CLOSED for 45 days. The Road Zipper machine will come out of storage.
By Memorial Day – Northbound Peter's Creek Bridge is reopened.
Figure 2. Three lanes of traffic will be maintained on the open bridge and the middle lane will alternate directions depending on the time of day.
Changing Traffic Patterns
During this construction drivers are encouraged to utilize the full length of all open lanes through a merging technique called the "zipper merge." Drivers remain in both open lanes of traffic until one comes to an end. Drivers in the lane that is ending use their turn signal and take turns merging into the open lane. Drivers in the open lane must consistently let drivers in the other lane merge into their lane. When correctly done, zipper merging can reduce congestion by up to 40%.
Figure 3. A graphic example of how to zipper merge.
Check out this video from our colleagues at the Utah Department of Transportation for a video demonstrating the zipper merge:
You might be wondering how we're going to move the concrete medians separating traffic every day and allow the middle lane of traffic to alternate directions. Enter the Road Zipper! This machine drives down the median, picks up the heavy concrete dividers and sets them down in their new position. This will allow the crews to shift the median along the 1,532-foot-long bridges twice a day in as little as 15 minutes!
Check out this video of a Road Zipper in action:
The northbound Knik River bridge is named after Sergeant James Bondsteel, a recipient of the U.S. Medal of Honor. Born in Michigan, Sergeant Bondsteel served with the U.S. Marine Corps in Korea and then with the U.S. Army in Vietnam. His actions during the 1969 Battle of Anloc in Vietnam earned him the Medal of Honor.
After retiring in the 1980s with over 20 years of military service, Sergeant Bondsteel moved to Alaska where he worked as a counselor at the Wasilla Vet Center and the U.S. Veteran's Administration in Anchorage. Tragically, Sergeant Bondsteel was killed on the northbound Knik River bridge in 1987 at only 39 years of age when a trailer of logs became detached from a logging truck and crashed into his vehicle.
In 2002 the northbound Knik River bridge was named the "Sergeant James Bondsteel Bridge of Honor" to commemorate his life. While working on this project, we will not only preserve the structural integrity of the bridge, but also remember and honor the man it is named after, Sergeant James Bondsteel.
Why is there a bump on the approach to the bridge?
Why do the bridge decks seem unfinished and unpaved?
Why didn't you repave the northbound (toward Mat-Su) bridge last fall?
How are you going to fit three lanes of traffic on one bridge?
Why can't you work one lane at a time and keep both bridges open?
Why don't you work nights?
Why aren't you widening the bridges?
Did DOT&PF buy the road zipper machine just for this project?
Why did you reopen the Knik River Bridges with concrete that feels unfinished?
Will you use the Road Zipper again?
Brendan Dougherty
DOT&PF Construction Project Engineer
Email: brendan.dougherty@alaska.gov
Project Phone Number: (907) 522-5055
Jason Lamoreaux
DOT&PF Construction Project Manager
Email: Jason.Lamoreaux@alaska.gov
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