The Dreaded Closure of I-376 Is Coming. Here’s What to Expect.

PHOTO BY OLLIE GRATZINGER

If you regularly travel on Pittsburgh’s highways, you’ve probably seen the signs declaring what’s to come: A 25-day total closure of a large portion of I-376 from July 10 to Aug. 3.

The reason: workers will be replacing the Commercial Street Bridge, a major throughway near the Squirrel Hill Tunnel that PennDOT says is traveled by more than 100,000 cars in each direction each day. 

The $95 million project can be a source of stress for folks who rely on the parkway.

Already, some roads adjacent to the project zone have closed; on June 29, Commercial Street, Forward Avenue and the Nine Mile Run Trail closed to all traffic in the area near the Commercial Street Bridge — closures that will remain in place around-the-clock through August. Crews are performing what PennDOT calls “preparatory work” leading up to the demolition. 

PennDOT has suggested a variety of detours to reroute traffic around the closure. Interstate detours are recommended for trucks or drivers just passing through, while local detours are available to cars heading to a destination in or near the project zone. As per PennDOT’s website, here are the step-by-step detour instructions:

Interstate Detour Westbound

• From westbound (inbound) I-376, take the Wilkinsburg (Exit 78B) exit toward PA 8 North
• Merge onto Route 8 (Ardmore Boulevard)
• Continue straight onto Route 8 (Penn Avenue)
• Turn left onto Fifth Avenue
• After going through Oakland, take the ramp to the left for westbound I-376. Use caution for opposing traffic
• Merge onto the Boulevard of the Allies and stay in the right lane to merge onto westbound I-376 toward Downtown/Fort Pitt Bridge
• Continue straight to merge onto westbound (inbound) I-376

Interstate Detour Eastbound

• From eastbound (outbound) I-376, take the Forbes Avenue/ Oakland (Exit 72A) exit
• Merge onto Forbes Avenue
• Turn left onto South Bellefield Avenue
• Turn right onto Fifth Avenue
• Turn right onto Route 8 (Penn Avenue)
• Bear right to continue on Route 8 (Ardmore Boulevard)
• Take the ramp to 376/22/30 toward Pittsburgh/Monroeville
• At the split, bear left to eastbound 376/22 toward Monroeville
• Merge onto eastbound (outbound) I-376

Local Detour Westbound

• From westbound (inbound) I-376, take the Edgewood/Swissvale (Exit 77) exit
• At the end of the ramp, turn left onto South Braddock Avenue
• Continue onto the Rankin Bridge
• Turn right onto Route 837 (River Road)
• Continue onto Route 837 (8th Avenue)
• Turn right onto the Homestead Grays Bridge
• Continue onto Browns Hill Road
• Continue straight onto Beechwood Boulevard
• Follow signs for westbound I-376 toward Pittsburgh
• Take the ramp to westbound I-376 toward Pittsburgh

Local Detour Eastbound

• From eastbound (outbound) I-376, take the Squirrel Hill/Homestead (Exit 74) exit, continuing straight onto Beechwood Boulevard toward Homestead
• Continue straight onto Browns Hill Road
• Continue onto the Homestead Grays Bridge
• Turn left onto Route 837 (8th Avenue)
• Continue straight on Route 837 (River Road)
• Turn left onto the Rankin Bridge
• Continue onto South Braddock Avenue
• Bear right to merge onto eastbound I-376 toward Monroeville

PennDOT is also recommending alternative routes for drivers coming into the city who would usually take I-376. Major throughways such as I-76, I-79, PA 28, PA 48 and PA 148 are utilized in the alternative routing.

I-79 and I-76 are the premiere routes from the north and west — although bear in mind that I-76 is the Pennsylvania Turnpike, and travel on the road may incur tolls. PA 28 is the most efficient way to get to the East End or eastern suburbs from the city proper, and PA 48 and PA 148 can get folks coming toward Pittsburgh from the south to the eastern suburbs without interacting with local or interstate detours. 

MAP COURTESY OF PENNDOT

There are significant financial incentives for the construction crews to finish early — and significant financial penalties if they finish late; a mailer sent to local residents earlier this week notes that the dates are tentative, “as unforeseen issues may arise during the project.” The same mailer tells folks to “expect heavy delays” and encourages anyone who is able to work from home or use alternative modes of transportation, like carpooling, biking or hopping on a PRT bus. 

For cyclists, PennDOT recommends bypassing the Commercial Street Bridge zone by utilizing Forbes Avenue, Beechwood Boulevard and Summerset Drive — safely avoiding the construction and demolition corridors as well as high-speed roads. 

As for public transit, PRT says commuters can park at one of the various park-and-ride lots to take a bus that will use the Martin Luther King Jr. East Busway to bypass the majority of traffic congestion. 

“Public transit offers commuters an opportunity to avoid some of the worst congestion,” PRT CEO Katharine Kelleman says. “Once our buses reach the East Busway, they’re traveling in their own dedicated corridor instead of sitting in traffic. If you’ve never tried PRT for your daily commute, this is a great time to give it a try.”

PRT also says it will temporarily suspend its own construction projects, like the University Line project in Oakland, during the Commercial Street Bridge closure. 

For real-time updates on traffic conditions, call 511, download the 511PA app or follow 511PA on X.