Water Markets in Colorado: Past Performance and Needed Changes

Abstract

The evolution of water law provides a fascinating example of the responses of law to changing social and economic conditions. xcScott and Coustalin 1995 and xcMiller 1996 have provided the details of water law change from Roman times to the 20th century. The law of prior occupancy (an early version of the priority doctrine), wherein the earliest water users had first call on available water, was adopted in England from Roman Law. At the start of the industrial revolution, it became clear that these historical uses were preventing water access for the newer, more technical industries. To accommodate these needs, a “reasonable use” doctrine evolved, allowing new activities access as long as they did not “unreasonably” reduce availability for others or “unreasonably” degrade water quality. This was the “riparian doctrine” of English Common Law that was brought to the eastern U.S. by the English settlers. Until the post World War II period, the doctrine served these well-watered regions well enough, although “reasonable use” remained vague and ultimately had to be defined in court.