Meeting Colorado's Water Supply Needs: Opportunities and Challenges

A whitepaper, found on the Colorado Water Institute of Colorado State University website, addressed the ramifications of conservation and improved efficiency of the state's water by the agricultural industry. This document sought answers to the following three questions:

"• Can "agricultural water conservation" result in transferable yield for new uses?
• Does increasing irrigation efficiency result in transferable yield for new uses?
• Does increasing irrigation efficiency and other conservation practices benefit existing
uses?" (p. ES-1).

To present their argument, the Colorado Agricultural Water Alliance distinguished agricultural water conservation from irrigation efficiency. For their purpose, the group stated that "Ag water conservation refers to practices that reduce historical consumptive use, while irrigation efficiency refers to practices that decrease nonconsumptive losses such as runoff or deep percolation of irrigation water" (ES-1). Similarly, the Alliance found it necessary to differentiate "saved and salvaged water" from water not used by agriculture because of a "reduction of crop consumptive use" (ES-2). The group created a new term, "'Conserved Consumptive Use Water' . . . to describe water that is part of the consumptive use of a water right that is removed from an irrigated cropping system" (ES-2).

Approximately one-third of Colorado farmers, according to the document, engage in improved water irrigation efficiencies, such as "drop nozzles, low-pressure delivery systems, irrigation scheduling, minimum tillage, and other techniques" (ES-2). These improvements, however, do not increase the amount of water available to farmers for transfers to municipal water buyers. The authors contend, "A primary factor is that the amount of water legally transferable is an irrigator's historic consumptive use, not the amount of water diverted" (ES-2).

Colorado water law imposes this restriction. Changes in agricultural practices decrease water use--reduction in irrigated acres, planting cool rather than hot weather crops, planting crops with shorter growth patterns, watering less than prescribed amounts, and treating a field to reduce evaporation through mulch or other applications. Adverse risks from water reduction, the authors explain, include " irrigation system failure, pests, or drought" (ES-3). Conservation measures increase agricultural transaction costs, such as labor, equipment, and operation.

The Alliance listed water conservation benefits that could accrue to the basins in the state that instituted conservation practices, that is, reducing "diversion of water to the farm, creating benefits such as improved water quality, allowing more water to remain in the streams, reduced waterlogging of soils, and reducing energy costs for pumping" (ES-3). The Alliance reiterated, however, that the benefits would not increase the amount of water that could be transferred to a municipal or any other user.

To maximize water consumptive and non-consumptive use in the state, the Alliance appealed not only for agricultural conservation but also for an increase and better utilization of the state's water storage. The group mentioned monetary incentives to farmers to offset risks and losses of installing conservation tools and equipment. They also anticipated a need for clarification on legal and administrative issues, especially the definitions of salvaged and saved water. Finally, they requested a basin-by-basin examination of the effects of agricultural water conservation on the priority system and compact agreements.

Meeting Colorado's Future Water Supply Needs Opportunities and Challenges Associated with
Potential Agricultural Water Conservation Measures. (2008). Colorado Agricultural Water Alliance.