SAN FRANCISCO (KPIX 5) — A San Francisco Muni line had to be re-routed after a major pothole was discovered near Moscone Center at 4th Street and Folsom.

Crews working to fix the pothole near Folsom and 4th. (CBS)

The pothole was called in by a Muni operator late Tuesday night and by Wednesday afternoon, the 8 had to be re-routed around the hole as crews worked to fix it.

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“Rain and water is really the worst enemy of pavement. If there’s a little crack and rain gets in there, it makes the road much vulnerable to a pothole,” said Rachel Gordon from San Francisco Public Works.

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“If you have lots of traffic, if you have a little bit of damage, that’s when a pothole forms.”

San Francisco averages 350 potholes a month during the dry months and as many as 1,800 per month during the rainy season. Some re-emerge multiple times, leaving crews feeling like they’re playing pothole whack-a-mole.

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“Sometimes you might fill a pothole in one location on a Tuesday and it might be back on a Friday, and we have to patch it again. The fix, the patch doesn’t always stay as strong as it should when the weather is wet and there’s not hot asphalt on there,” Gordon said.