Contact Thor customer care and ask them to send you the fresh and waste water diagrams. You can either call them or fill out the form at this website
https://thormotorcoach.com/customer-care/
I sent them as request at 11 am yesterday and had the requested drawings by 4 PM.
As a note, the diagrams are marked confidential and proprietary and requires Thor's express written permission to be posted on the site or given to someone other than the intended recipient.
Do you have a shower door or curtain on your coach? Some folks found the shower door frame is not adequately sealed where it meets the shower stall and water is leaking though there.