Mayflies have been hatching along the Susquehanna River, and the Route 462 lights are off

Mayflies have been hatching along the Susquehanna River, and the lights on the Route 462 bridge have been shut off for more than a month now to help keep their carcasses off the structure.

Several hatches have been seen this year, said Mark Stivers, Columbia borough manager. A recent one left the mayfly carcasses an inch and half deep at Columbia Crossings.

When mayflies closed the bridge

It has been eight years since officials had to close the Veterans Memorial Bridge because swarms of mayflies caused crashes on the structure.

The insects are attracted to the lights on the bridge, and piles of bug carcasses littered the structure.

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When will the lights come back on?

For years now, Columbia has shut off the lights on the historic bridge to prevent problems when the mayflies hatch.

It will remain unlit until officials know the mayfly hatches are over, Stivers said. Then the lights will be turned back on.

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This article originally appeared on York Daily Record: Veterans Memorial Bridge remains unlit because of mayfly hatch