A video of an unreleased prototype of the game was showcased by two of the developers of the game, Tim FitzRandolph and Chad Cable.

This prototype has many things that are not in the final game, such as the ability to cut Algae and two different shades of Dirt.

Chad Cable's article about Where's my Water confirms that the prototype was created in Unity, unlike the final version which was written in C++. It also confirms that this is the first prototype of Where's my Water.