Keep them in a separate pool or mandate pool diapers. Consider this thought experiment. You have a movie theatre where the people on the balcony may pee and that pee drips down on the faces of people below them. Would this be considered acceptable and would I be considered insensitive for complaining and insisting that those people wear diapers or else should not be in a place where their pee ends up in the faces of others? Why is it acceptable in a swimming pool?
> Keep them in a separate pool or mandate pool diapers
Pool diapers have roughly zero effect on urine (the whole reason for pool diapers is to retain feces in an environment where liquid absorbent diapers inherently will fail completely.) So, the pool diapers plan for dealing with urination is unworkable.