Where did the water go???

newell

     We just returned from the last trip of the season.  We drained out the holding tanks on our 2017 T@Bs at the campground.  We thought it might be a good idea to put a couple of gallons of clean water with a little dish soap in the black water tank to splash around during the eight hour drive home.  
     Here I am a week later getting ready to winterize the camper and when I went to drain out the soapy water, the tank was practically empty.  The trailer was tilted slightly forward so I know anything that was in there was coming out.  I suspected a leak so I put two more gallons of clean water in the tank and I was unable to find any evidence of a leak under or inside the T@B.  At am at a complete loss where that water has gone.  I'm not so concerned now because I'm putting it up but I don't want to get to a campground next season only to find out we have a major problem. Has anyone else had a similar problem.  I'm out of ideas.  Thanks.

Sharon_is_SAM

Is it possible you added the soapy water when the drain valve was still open?

ScottG

The holding tanks are open to the environment via a vent pipe. I'd suggest evaporation, but a couple gallons in the space of a week seems highly unlikely.

newell

Yea Scott I agree.  I'm beginning to think in the hustle of packing up I might have just drained it right back out.