Ocean City sinkhole: How are they formed, and what can cause them?

A star-spangled... sinkhole?

Motorists who journeyed into Ocean City, Maryland, over the Fourth of July faced major traffic congestion courtesy of a sinkhole, which was discovered at about 7 p.m. on Wednesday evening near the base of the Isle of Wight Bay Bridge.

The Ocean City Police Department warned motorists of intermittent closures on eastbound Route 90 from Route 589 and westbound lanes from 62nd Street in Ocean City back onto Route 90. Drivers were urged to use alternative routes such as Route 50 and Delaware Route 54.

Temporary repairs ensued, and were completed by 1 a.m. on Thursday, July 4. The Ocean City Expressway remained open to traffic while transitioning to one-way flagging operations during repairs, before resuming normal operations around 8 a.m.

Original story on sinkhole: Sinkhole opens up at base of Route 90 bridge into Ocean City: What to know

"Thank you to the Maryland State Highway Administration crews that worked throughout the night on the repairs," the OCPD said online.

"It was pretty easy," Mark Crampton, District Engineer for the Maryland Department of Transportation State Highway Administration (MDOT SHA), said of the repairs. "We were able to get some trained eyes on it to figure out, okay, what do we have and what do we need to go get."

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Can sinkholes form in Ocean City? Yes.

Although sinkholes rarely occur in Ocean City, they can happen.

Sinkholes are often created through erosion, which is caused by constant exposure to water.

"Sinkholes in Western Maryland are (often) associated with limestone. Our guess is that, in this case, it's probably tidal action moving water, and if it gets into a crack and starts to get the material behind it, it can start to wash things out," Crampton said.

"The bridge has been there a while, and you constantly have tides and things like that that work against it," he said, adding how it doesn't take much for water to get in.

"These are the things we'll look at with the bridge remedial folks to make the repairs, permanently fill any voids, and seal off any gaps to prevent water intrusions going forward," he added. "That'll be part of the more permanent fix as we get past the holiday weekend."

SINKHOLE OPENS IN OCEAN CITY: Sinkhole opens up at base of Route 90 bridge into Ocean City: What to know

Further repair work ahead on Ocean City's Route 90 bridge

The State of Maryland is hyper-focused on maintaining and improving its bridges.

"Maryland has one of the best, if not the best, bridge inspections across the country," Crampton said.

Further repairs are expected to be done to Ocean City's Isle of Wight Bay Bridge.

"We had emergency repair work done on the abutment to the bridge on MD 90 West," said the MDOT SHA. "A permanent repair will be done in a few days so we don't disrupt beach traffic."

Olivia Minzola covers communities on the Lower Shore. Contact her with tips and story ideas at ominzola@delmarvanow.com .

This article originally appeared on Salisbury Daily Times: Ocean City sinkhole: How are they formed, and what can cause them?