Water is the most important Resource for a population's Vital Needs.
Water is collected by the Water Collector from water like rivers or lakes in territories. After the Well Digging Knowledge is researched, it can also be gathered from underground sources by the Well.
Water is vital to a territory's growth. Lack of water will impose a penalty on Porcos' health, scaling up to -100% if no water is available. A territory lacking access to water will have its population die off over time.
Water can also used by certain industries such as the Potter, or the Laundry.
After Fair Exchange is enacted, water is the only distributable resource that does not require a Market stand or a Merchant in order to be distributed.