DOT to begin Glenn Highway pavement preservation next summer

Three weeks after the Matanuska River undercut part of the Glenn Highway, stabilization work continues taking place with crews working to widen the embankment and will be finishing it with riprap to prevent further erosion.

Meanwhile, the Alaska Department of Transportation and Public Facilities (DOT&PF) is conducting preliminary engineering, survey and field activities and final design for the upcoming Pavement Preservation Project between MP 66.5, near King’s River, and MP 92 near Cascade, as part of the DOT&PF’s Preventive Maintenance program.

The DOT&PF is planning to construct road and drainage improvements along the Glenn Highway as the existing pavement shows signs of deterioration and structural failure. Insufficient drainage ditches and missing, damaged, and/or failing culverts contribute to roadside erosion and structural damage. Guardrails and guardrail end treatments will also need replacing.

The planned improvements will address short-term immediate needs to extend the useful life and maintain the functional condition of DOT&PF roadways, thereby substantially reducing maintenance efforts and costs. However, the planned road construction does not include the area affected by the recent erosion.

“The Glenn MP 66.5 to 92 Pavement Preservation project will not include the area where the erosion repair work near milepost 63.6. Due to the imminent need to complete repairs quickly, DOT&PF Construction has been working with a contractor address the erosion damage as quickly as possible,” said Clint Adler, Chief, Mat-Su District Office of the Alaska DOT&PF

Adler says that DOT&PF recently stabilized the entire area (~1500’ long x ~30’ wide) near MP 63.5 of the Glenn Highway, and their contractor imported approximately 18,000 cubic yards of shot rock from the nearby State of Alaska Callison Pit, and that the Department is currently assessing the quality of the imported rock for long term application.

“This assessment will likely necessitate importing an additional 4,000 to 6,000 cubic yards of Class III/IV Rip Rap. Hauling and placing this additional Rip Rap would take up to 6 weeks. Traffic should expect minor lane restrictions during that period.”

The Pavement Preservation Project will resurface the highway, reestablish ditches and improve drainage, repair damaged structural sections, repair and replace culverts, install guardrail and guardrail end treatments, and signing and striping. Key goals are to maintain safety and preserve the level of service and function of the existing roadway until the Glenn Highway Rehabilitation project can be constructed. It also includes erosion protection where the highway is immediately adjacent to the Matanuska River, installing rip-rap protection along the road embankment at MP 71 and MP 76, and rockfall mitigation where rocks and loose material fall from eroding slopes onto the highway.

As survey and field activities are underway, a final design is expected sometime this summer, and Phase I of construction is expected to begin summer 2025 and continue for the next subsequent summers after.

For more information, please visit www.dot.alaska.gov/creg/1r/glenn66/