Pressurized Water System

Thinking of making a water supply system out of 4" PVC. It would be Sch. 40 and about 8 feet should give me 4.75 gal. I would mount it to the bottom of the trailer.
Has anyone tried to supply the water by adding an air valve (tire type) and pressurizing the system to about 60 psig with a tire pump?
As soon as the water press. starts to drop- - - -pump it up a little more.
Thoughts please.
- - - - - Bob
Has anyone tried to supply the water by adding an air valve (tire type) and pressurizing the system to about 60 psig with a tire pump?
As soon as the water press. starts to drop- - - -pump it up a little more.
Thoughts please.
- - - - - Bob