Reducing Agricultural Water Use in Arizona in Response to Climate Change.

The availability of adequate and affordable irrigation water is an issue of great importance to agricultural producers in Arizona where rapid population growth is generating competition for water, and drought is limiting water supplies.  Whether the current drought in the Colorado River Basin is the manifestation of climate change projections calling for a warmer and drier future, or is simply another long-lived regional drought is a point of debate among Arizona water users -- a debate is that has outlived its usefulness.  Water shortages are imminent and agricultural producers must adapt to a future with less water.  Producers are hesitant to accept the concept of anthropogenic climate change.  However, they remain interested in current and expected weather and climate projections which provide opportunities to discuss climate change.  Arizona Cooperative Extension has developed a Climate Science Program to complement its existing program in Biometeorology.  Both programs provide assistance to agricultural and urban stakeholders, government agencies and non-governmental organizations seeking assistance with weather and/or climate-related issues, including climate change adaptation plans. 

Proposed strategies for reducing agricultural water use include switching from surface to pressurized irrigation systems, improving irrigation efficiency, winter-centric crop production systems, deficit irrigation, fallowing programs and use of reclaimed water for irrigation.  Factors limiting implementation of water saving technologies include remote land ownership, variable rules regarding water use/transfer, and economic issues including high implementation costs.  Extension faculty with expertise in water, agronomy, biometeorology, soil science, irrigation and economics have been working on some of these concepts for many years to improve the overall efficiency of Arizona agriculture and are in position to provide guidance on several of the aforementioned water-saving strategies through workshops, publications and electronic/social media.  Other aforementioned strategies require additional research that is being directed by Extension faculty, often with financial support from the Arizona agribusiness community.