Glenn Highway bridge closure forces Birchwood detour through June 2

The northbound Glenn Highway bridge closed April 18 for 45 days of deck preservation work. All traffic now squeezes onto the southbound span with 11-foot lanes and a 45 MPH speed limit.

The closure also shut the northbound on-ramp from Birchwood Loop Road to the Glenn Highway through June 2. Drivers heading to the Mat-Su now detour via Old Glenn Highway to reach the next entrance.

The bridge work is part of a $20 million to $30 million contract covering the Peters Creek and Knik River bridges. The project includes bridge deck and expansion joint repair, guardrail work, and paving. Completion is scheduled for August 15, 2026.

Lane configurations shift multiple times daily to accommodate peak commuter flows between Anchorage and the Mat-Su. Two lanes stay open in the peak direction: Anchorage-bound in the morning, Mat-Su-bound in the afternoon.

On Sundays between 7 a.m. and 8 a.m., barriers shift to allow two southbound and one northbound lane. Mondays through Fridays between 11 a.m. and noon, barriers shift to allow two northbound and one southbound lane. Tuesdays through Fridays between 3 a.m. and 4 a.m., barriers shift to allow two southbound and one northbound lane. On Saturdays, two northbound and one southbound lane are open all day.

More information is available at www.glennbridges.com. Alaska 511 provides real-time traffic updates for the work zone.