For dogs without a microchip or other sort of ID on them it is 72 hours until they become County property if not claimed. Dogs with a microchip or ID are held for 10 days. Then they are evaluated, which might take a week or more, for adoption.
Additional information; adding on to n.uravich's answer: Then, if they are not deemed "adoptable" or if they don't have the space to house them (and no foster homes available for the dog) they will be killed.
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