Heh, well you can always use [MOD] Stonehearth Cafe (Cooking And Farming Expansion) 1.7 by Froggy. It’ll add new crops, recipes, animals, and decorations for your town. Then your Mason will be able to craft wells for water, but your hearthlings will also require water like they do food. It’s a great addon and I highly recommend it!
If ya mean water in the environment, there’s not currently a way to add it after the map has generated (that I know of). If you’re looking to add more water to your maps though, try out Rivers mod by BrunoSupremo. It’ll add rivers when the maps are generated to choose a location.
The Stonehearth team is currently working on the water mechanics. Hopefully once they get it all ironed out, there will be more options. 