As the western population grows and the demand for water increases, Native Americans have become major players in the political process which determines who can use water and how much they can use. In one way or another, all of the tribes in this study have played a part in this process. Some have clearly had more success than others, and for many, the successes they have achieved have come at great cost. By design, state governments largely determine who has rights to how much water in the West. Although each state has its own set of controlling legal principles, the doctrine of Prior Appropriations serves as a unifying principle.
Water is scarce in most parts of the West.
Often those who use water live far from where they draw it. Prior Appropriation is a uniquely western way of allocating water. Actually the principle was generated over a dispute over mining claims. A miner was diverting water from a stream, in order to extract gold. Another miner filed a claim up stream and began diverting water, thus depriving the first miner of his water.