Human beings are made up of up to 60% water. One of the first things scientists look for in a potential second Earth is whether it contains water, it being a necessity for life.
The Native American demonstrations last year at Standing Rock in the Dakotas was all about protecting the water. They branded themselves as "water protectors." I feel bad referring to this as a brand, but this really resonated with people. Water has mythological meaning that works when trying to persuade people to your side.