PITTSBURGH (KDKA) — For Pittsburgh-area drivers who depend on the Liberty Bridge to get around, prepare for some long traffic delays in the coming days as crews assess and repair significant damage from a fire.

PennDOT says the span is now closed indefinitely in both directions after the fire sent a thick cloud of smoke billowing into the sky over the city around 1 p.m.

“We looked over, and the Liberty Bridge was on fire,” witness Jim Thompson said. “All the working tarps and all that stuff was all caught and flames were flying.”

My friend works in the BNY building. The Liberty Bridge is on fire. pic.twitter.com/hbHNXSllof — Sean Gentille (@seangentille) September 2, 2016

The Liberty Tunnel was also closed down, and water traffic underneath the bridge was halted for safety reasons.

PennDOT District 11 Executive Dan Cessna said about 30 feet of steel framework beneath the span was damaged.

“It’s a small, isolated area,” said Cessna. “But it’s a very serious issue because it’s a buckled compression member, and on a deck truss like this, any member like this that could be compromised could cause a catastrophic failure. So, this is a serious issue that we’re monitoring.”

PennDOT: Steel beam buckled & bent beneath Liberty Bridge as a result of today's fire; beam has to be replaced. pic.twitter.com/eUw5B1NQyK — Ralph Iannotti (@IannottiRalph) September 2, 2016

He says he’s vitally certain the damaged steel will have to be replaced.

Cessna called it a “freak thing,” saying it’s absolutely the last thing they wanted to have happen on a major artery.

LIBERTY BRIDGE FIRE PHOTO GALLERY

The fire apparently started when a tarp caught a spark from a workman’s blow torch. The flames then spread to some plastic pipes on the bridge.

No workers were injured.

The bridge will be closed at least through the long Labor Day Holiday weekend, and possibly longer. But Cessna said crews will be working around the clock over the weekend to assess, monitor and repair the bridge.

“From a standpoint of getting the bridge reopened, if everything goes as planned, we’re working on the design right now as we speak,” he said. “At this point, expect the bridge to be closed the entire weekend and the beginning of rush hour when folks would plan to return on Tuesday. But know that we’re committed to getting this thing repaired as fast as we can.”

PennDOT says the Liberty Bridge and the inbound side of the Liberty Tunnel will remain closed until further notice. The outbound side of the tunnel and McCardle Roadway will remain open.

Bridge traffic is being detoured.

PennDOT’s recommended detours:

Northbound (Inbound)

• Take Route 51 (Saw Mill Run Boulevard) northbound

• Take the exit to I-376 West/US 19 South toward Carnegie/Airport/West End

• Take Exit 69A toward US 19 South/Banksville Road

• Keep left and loop back to I-376 eastbound toward Fort Pitt Tunnel

• Follow eastbound I-376 through Fort Pitt Tunnel and across the Fort Pitt Bridge

• For access to I-279 destinations follow I-279 signage, all other destinations take exit toward I-376 East/Monroeville

• Take the left exit 71A to Grant Street

• Turn left onto Grant Street

• End detour

Southbound (Outbound) From Downtown Pittsburgh

• Take Grant Street to I-376

• Take the ramp to West I-376 toward Fort Pitt Bridge/Airport

• Follow I-376 westbound across the Fort Pitt Bridge and through the Fort Pitt Tunnel

• Take Exit 69A toward South 19 Banksville Road

• Keep left and loop back to eastbound I-376

• Take Exit 69B toward South Truck US 19/Route 51 Uniontown

• Merge onto southbound Route 51 and follow back to the Liberty Tunnel

• End detour

Southbound (Outbound) From Westbound Route 885 (Boulevard of the Allies)

• From the Boulevard of the Allies take the ramp to North I-579 to I-279 Veterans Bridge Exit

• Take the Convention Center/7th Avenue Exit

• Turn right onto Grant Street

• Turn left onto 11th Street

• Continue straight onto the 10th Street Bypass

• Take the I-376 West Fort Pitt Bridge/Airport Exit

• Follow I-376 westbound across the Fort Pitt Bridge and through the Fort Pitt Tunnel

• Take Exit 69A toward South 19 Banksville Road

• Keep left and loop back to eastbound I-376

• Take Exit 69B toward South Truck US 19/Route 51 Uniontown

• Merge onto southbound Route 51 and follow back to the Liberty Tunnel

• End detour

Southbound (Outbound) From Route 380 (Bigelow Boulevard)

• From PA 380, take the Consol Center/6th Avenue Exit

• Take the 6th Avenue Exit

• Turn right onto Grant Street

• Turn left onto 11th Street

• Continue straight onto the 10th Street Bypass

• Take the I-376 West Fort Pitt Bridge/Airport Exit

• Follow I-376 westbound across the Fort Pitt Bridge and through the Fort Pitt Tunnel

• Take Exit 69A toward South 19 Banksville Road

• Keep left and loop back to eastbound I-376

• Take Exit 69B toward South Truck US 19/Route 51 Uniontown

• Merge onto southbound Route 51 and follow back to the Liberty Tunnel

• End detour

Southbound (Outbound) From I-279 Parkway North

• From southbound I-279, take the I-279 South Fort Pitt Bridge Exit

• Take the South I-279/To I-376 Fort Pitt Bridge/Airport Exit

• Take the West I-376 Fort Pitt Bridge Exit

• Follow I-376 westbound across the Fort Pitt Bridge and through the Fort Pitt Tunnel

• Take Exit 69A toward South 19 Banksville Road

• Keep left and loop back to eastbound I-376

• Take Exit 69B toward South Truck US 19/Route 51 Uniontown

• Merge onto southbound Route 51 and follow back to the Liberty Tunnel

• End detour

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