Security cameras recorded three people leaving the animals outside Peaceable Kingdom in Whitehall on Saturday.
The shelter workers want to identify the trio to help with an animal cruelty investigation.
"We don't know if these were the dog owners," Kathy Tomecek, the chair of the board of directors of Peaceable Kingdom, said. "We don't know why they did this. We don't know if someone knew of these dogs."
The shelter workers say it took them hours to clean pounds of matted hair off the dogs.
"We had volunteers work over five hours to get the crud, the hair, the filth off of these dogs," Tomecek said.
Some have more serious health issues. One dog has a broken ankle.
All the dogs will be up for adoption once they are checked out by a veterinarian.
"Well, we're hoping that they're not in too bad of a shape and we're hoping to find them their forever homes. We're hoping the rest of their lives will certainly be better than what they've come from," Tomecek said.
You can complete an application on the Peaceable Kingdom website if you'd like to adopt one of them when they are able to leave the shelter.
Since the dogs are in need of a lot of medical care, the shelter is accepting donations.
Anyone with information on those who dumped the dogs or the investigation is asked to call Officer Morgan with the Lehigh County Humane Society at 484-619-2074 or email firstname.lastname@example.org.