Anti-Grief

For this you will need:

-Sticky Pistons

-Cobblestone( or any type of building material)

-Red stone

-Red stone Torch

-Repeater

-switch

Start out with a roof of the size of your liking and leave a trail of cobblestone

Place a rectangle of cobblestone and place 2 or more sticky pistons

Put the red stone behind the piston to connect it together

Add 2 more levels so the water can go there and the water at the top

Make stairs so the redstone can flow down

Make the redstone path and stop wherever you are

Put the repeaters down.

Put a switch at the end so you can turn it off and on

Test your invention so you can see if it works

Always protect your red stone from the water