On our 2004 tioga, there are two valves behind an access cover on the outer bathroom wall. Small valves are hard to see, hard to reach and stiff to turn off and on. Their purpose is to drain all of the plumbing lines of water as when you are sanitizing the tanks and water lines with weak bleach/water solution or when winterizing. If one or both valves are not closed all the way, you may see water leaking from a small hose under your rig. If they are not closed completely, your fresh water pump may run on after you shut off the faucets. On some rigs these valves are hard to locate, consult the RV manufacturer if still in business or an RV repair shop may be able to help locate on your rig.