State and federal officials hope to be able to reopen beaches up and down the Delmarva peninsula to swimming by this weekend, but are still puzzled over the source of medical waste that led to the closures beginning Sunday.

Ocean City is back open for swimmers and surfers, according to a post on the Town of Ocean City's website. The water had been closed since Sunday after medical waste was observed washing ashore, according to the Maryland Park Service.

Swimming is still off limits in Ocean City as medical waste, including hypodermic needles, continue to wash ashore. Ocean City Emergency Services Director Joe Theobald said in a statement Monday evening the amount of debris has “significantly decreased,