Help!!

My girlfriend gave my 2 month old basset hound a bath this morning. He apparently drank a good amount of the bath water. We finished up with the bath, then he napped for about 30 minutes. He woke up and had an accident (I think he was on his way over to the bell system we have, just didn’t get there in time) since then, I have been outside with him, it has been non stop peeing for about 45 minutes. I’ve brought him in twice and both resulted in an accident almost immediately. How long will it take to get it out of his system roughly?