The inbound Armstrong Tunnel is scheduled to close for a $13.1 million rehabilitation project.

The closure is expected to start at 6 a.m. March 4, according to county officials. It’s not expected to reopen again until winter 2024.

The right lane for inbound traffic on Second Avenue also will close at the road’s intersection with the Armstrong Tunnel.

Cars will be detoured using Second Avenue, Ross Street and Forbes Avenue.

A truck detour will use Second Avenue, B Street, First Avenue, Grant Street, Boulevard of the Allies, Commonwealth Place, Liberty Avenue, Fifth Avenue, Sixth Avenue and Forbes Avenue.

County officials said they expect the inbound Armstrong Tunnel to reopen during winter of 2024.

At that time, crews will close the outbound tunnel and adjacent sidewalk. Restrictions there are expected to end in the spring of 2025.

About 11,000 vehicles use the tunnel daily.

“While this project will certainly impact traffic in and around Downtown Pittsburgh, it is necessary to extend the life of the tunnel and to ensure driver and pedestrian safety within it,” county officials said in a statement.

Recent inspections showed deterioration of the tunnel’s concrete, ceramic tile and lighting fixtures that need to be addressed. Its safety systems also need to be brought up to current standards, officials said.

The rehabilitation project will include concrete repairs, as well as removal of the ceramic tile liner which will be replaced with fireproof wall panels. Work also will include cleaning masonry at the tunnel exits and entrances, upgrading lighting, electrical and fire detection and suppression system upgrades, installing a CCTV monitoring system and placing new pavement, curb, sidewalk, signage and pavement markings.

Once the tunnels reopen, drivers can expect a new lane configuration intended to slow traffic and improve safety.

There are now two, 10-foot-wide lanes with no shoulders in each tunnel. After the project is completed, the inbound tunnel will have one 12-foot lane with four-foot shoulders, except at the exit where there will be two right-turn lanes.

The outbound tunnel will have one 12-foot lane with 2- to 3-foot shoulders except at the exit, where there will be a left-turn lane and a straight/right-turn lane.

The existing sidewalk adjacent to the outbound tunnel, which currently measures three feet and nine inches, will be widened to six feet and three inches, except at its entrances.

Robinson-based Mosites Construction is performing the work.

The Federal Highway Administration is paying 80% of the cost, while the county is covering the remaining 20%.

Opened in 1927, the 1,298-foot-long tunnel is named after former County Commissioner and Pittsburgh Mayor Joseph G. Armstrong. It is listed on the National Register of Historic Places.

The Armstrong Tunnel’s last rehabilitation project was performed between 1989 and 1991.

Copyright ©2025— Trib Total Media, LLC (TribLIVE.com)