Our water tanks' tops sit within surround frames attached to the floor and some bolts prevents the tanks from moving sideways towards the outside. The gray and poo tanks are located similarly.
But there was some leakage, after the last camping we took with some nasty crack jumps. The
plumbers in Calgary, showed up quick after we noticed the issue and though some time was taken in realigning the tanks and clearing the leakage, they did good work even on the RV.