Fresh water tank

Hi, This is probably a stupid question but would someone please tell me where the fresh water tank located in my 2552.  The manual does not explain where it is or how to empty it.  This is the first time I filled it up and I want to empty it and fill it again.  Thanks

It is under the passenger side bed, but I don't know how to drain it now that the newer models don't have a drain valve on the exterior under the fill port.

Tank is under the passenger side bed.  Small trap door in the particle board allows you to reach in from the top and turn the drain valve to drain tank.  You can all  so reach the winter by pass valve.

Thank you for your help.

 There  r no stupid question.