Artificial recharge of ground water in Colorado: a statewide assessment

Abstract

Ground water aquifers can be used as reservoirs to provide increased water storage capacity in Colorado through an intentional, engineered water recharge process to aquifers called "artificial recharge." CGS has completed an assessment of the current and potential use of artificial recharge in our state. The report widely addresses several pertinent aspects of artificial recharge including the reasons for using the technique; the current methods or technologies used; where artificial recharge is being done in Colorado, the US and internationally; types of aquifers that can be used for artificial recharge and which Colorado aquifers are best suited for water storage. An inventory of artificial recharge projects within Colorado identified 19 active operations as of 2004. A weighted ranking system was established to evaluate the key physical properties of the state's sixteen highest-potential unconsolidated aquifers and 29 highest-potential consolidated aquifers. The evaluation of the available storage capacity in Colorado's highest-potential aquifers was guided by the desire to find opportunities to develop large-scale artificial recharge projects, i.e., defined as having storage capacity in excess of 100,000 acre-feet. Thirteen of the sixteen primary unconsolidated rock aquifers have sufficient storage capacity to accommodate a large-scale project. In aggregate, the lower South Platte River alluvium and the San Luis Valley alluvium have the capacity to store in excess of one million acre-feet. All but two of the 26 primary consolidated rock aquifers also have sufficient storage capacity. Because of their large areal extent and head freeboard, the majority of these aquifers can store millions of acre-feet of water.