Colorado is a headwaters state supplying water to over five million Coloradans, 18 other states and Mexico, and does so through reliance on precipitation, mainly in the form of snow (Water Education Colorado [WEC], n.d.a). Colorado’s Department of Local Affairs [DOLA], 2015) projects the state’s population to nearly double to 8.6 to 10 million people by 2050. As Colorado’s Water Plan (State of Colorado, 2015) points out, this population growth will create a significant need for an additional 600,000 to one million AF of water annually to meet future municipal and industrial (including self-supplied industrial) demands. Some areas of the state (e.g. South Denver Metro area) already need to replace nontributary groundwater supplies; therefore, simply acquiring new supplies within the state to meet future needs is not an option.
To further complicate growing water supply needs, supplies are not necessarily where demands are: approximately 80% of Colorado’s water falls and flows west of the Continental Divide, while 80% of the population and the majority of irrigated acres are found east of the Divide (WEC, 2014; Colorado Water Conservation Board [CWCB], n.d., 2011). Although the West Slope is projected to grow at a faster rate than the Front Range, the Front Range basins (Arkansas and South Platte) will continue to have the largest populations in the state (CWCB, 2011).