The Chalice mod adds a few new items to both provide and destroy liquids in the game. The Sea Chalice provides an infinite source of water. And the void chalice provides an infinite container to destroy water. So if you ever need to fill an area with water, the chalice is a choice tool.
If you happen to place some water in an undesirable spot or simply want to remove water from anywhere, then use the void chalice to clear those spots. It doesn’t really work to clear large bodies of water since that spot will just refill, but it does a good job of removing latent patches in weird spots.
You can even use it to destroy lava blocks if need be.