Fresh Water Tank Siphoning

[ken white]

After I fill my fresh water tank at home, I loose about 2/3 of the tank by the time we get to our boondocking destination. The last time we travelled, I noticed the water is coming out of the overflow tube behind the rear wheels even after being stopped. So it looks like I might have a fresh water tank venting problem since it appears there is a vacuum being created which is causing the siphoning.

Is anyone else having this problem? If so, how did you fix it?

TIA

Ken

[ken white]

Added some plugs to the overflow drain line, for travel only, and it has stopped the tank from siphoning while driving.

:)