On Saturday, the 640-foot-long Panther Hollow Bridge in Pittsburgh’s Squirrel Hill neighborhood was closed unexpectedly.

The reason given then was “an abundance of caution.” On Monday, the need for that caution was clarified: Steel trusses were found to be corroded. Inspectors said they could weaken areas of the bridge. They recommended closing the bridge until further notice.

To the city’s credit, action was taken immediately.

To be more cynical, other cities can shrug off the recommendations as something that happens elsewhere. Pittsburgh can’t. It’s less than three years removed from the Fern Hollow Bridge collapse in January 2022. The bridge that took its place will have its second birthday in just two months.

In February, the National Transportation Safety Board delivered its findings in the collapse. It was human error, specifically due to neglect of maintenance and ignoring inspections that reported things like steel devoured by corrosion and rust.

Panther Hollow is the latest bridge issue. The Charles Anderson Bridge has been closed since February 2023. That move also came after inspectors reported concerns. Repairs and rehabilitation of that structure will cost $56 million. It isn’t slated for completion until 2026.

Mayor Ed Gainey started his tenure with a fallen bridge. He pledged last year he would never hesitate to close a bridge if necessary. He has lived up to that commitment.

And Gainey’s administration cannot be faulted for years of neglect — or for the lack of a bottomless well of money to correct those deficiencies.

But just because there isn’t someone to blame doesn’t mean there aren’t problems to fix.

The city of Pittsburgh learned a lesson with the Fern Hollow collapse. It has prioritized responding to bridge and infrastructure emergencies.

That’s not the only lesson, however. The city — like the state and like other areas — must make faster progress. Bridges are not just a means to an end. They are a responsibility. Building a bridge is a promise to the people who will depend upon it. Fulfilling that promise requires not just the cost of construction. It demands the ongoing obligation of upkeep.

Pittsburgh failed on that in the past. It is making strides to correct that damage. But nothing will get better until bridge repair and maintenance stop being reactive and becomes proactive.