water purification plants

we all know two biggest uses of land are farms/silos and watermills they have sorted the farms out with a lvl 6 upgrade and improved silos so how about the same with watermills my idea is make use of the water around the island and make water purification plants that use theses spots like the floaters do... would at least fit with them filtering water

+1

If this would be very limited, maybe even bought for gems, this would sound cool.
Also we could build a harbor and send off fishing ships from there.