Well

A well can be used, in conjunction with a Bucket, to acquire water.

How to aquire (in assumption nothing changed)
First you need a dowsing rod in order to see underground springs in order to build the well. Keep in mind that the dowsing rod, even though it only takes 1x1 inventory space, requires two hands to use. When you are holding it, an occasional pulse will radiate near you. If an underwater spring is nearby, then an indicator will point you towards the direction of the spring. The spring itself will look like a tiny patch of water which you can build the well upon.