In the 1860s, Colorado adopted a set of laws regarding water use and land ownership known as the Colorado Doctrine. This doctrine established four essential principles of the state’s water law that helped distinguish it from Riparian Law, which is the water law framework commonly followed in wetter, humid portions of the U.S. where there is less concern for reduction of overall flows (Water Education Colorado [WEC], 2015; Colorado Water Conservation Board [CWCB], 2011; OpenEI, 2017):
- The state’s surface and groundwater is a public resource for beneficial use by public agencies, private persons and entities;
- A water right is a right to use a portion of the public’s water supply;
- Water rights owners may build facilities on the lands of others to divert, extract, or move water from a stream or aquifer to its place of use;
- Water rights owners may use streams and aquifers for the transportation and storage of water.
Prior Appropriation System
The prior appropriation system, affirmed by Colorado’s Constitution and termed the “prior appropriation doctrine,” is Colorado’s legal framework which regulates surface water and tributary groundwater use (Colorado Division of Water Resources [DWR], n.d.; WEC, 2015). This system of allocation determines who uses how much water, the types of uses allowed, and when those waters can be used, with the main objectives of preventing water waste and providing a system of allocation around a scarce resource (CWCB, 2011; DWR, 2012). Provisions of the 1969 Water Right Determination and Administration Act, as well as the 1965 Ground Water Management Act, primarily govern the prior appropriation system (WEC, 2015; DWR, 2012; Colorado Geological Survey [CGS], 2003).