This month, I have been thinking a lot about irrigation, irrigation technology and irrigation efficiency. One of the reasons this is preoccupying me is the recent publication of a March 2017 report entitled “Management of Agricultural Energy and Water Use with Access to Improved Data.” The report conveyed the research, results, findings and recommendations of the Center for Irrigation Technology at Fresno State and AGH2O on the topics of 1) information services, software and hardware available to growers 2) the adoption rate of these technologies and others and 3) the gaps, strategies and future technologies to improve water and energy management in agricultural settings. This report supported many of the observations from the “Deep Dive” on Water Management Technology that Western Growers, the Mixing Bowl, City of Fresno and others held earlier in the year, and expands immensely on the issues associated with new technology and its adoption to improve precision in water use. In the Executive Summary of the Report, the authors condensed responses from growers and others to the specific question: “Are there any barriers to you adopting new water management technology into the following: ease of use, costs (to install, operate, maintain), reliability of data, learning curve and practicality? This is consistent with concerns that surfaced in WG’s Deep Dive. While growers are wary of new irrigation technology, they still have a high level of interest in deploying technology that can increase irrigation efficiency and reduce energy costs.
Western Growers, through its Center for Innovation and Technology, has identified water efficiency as a priority and we are working with growers and startups in this space to help accelerate the availability of vetted tools that will help reduce costs and improve efficiency. But while these high-tech solutions for irrigation systems may be the next level for driving precision into agricultural water use, there is still plenty of blocking and tackling to do with today’s irrigation systems in California and beyond.
In the recommendations section of the CSUF Report, one of the first observations is that distribution (or emission) uniformity (DU) is of critical importance. This finding is consistent with Western Growers, Toro and Simplot research that was reported out May 2016 in “Irrigation System Evaluations (A Look at Distribution Uniformity)” where we evaluated the performance of four Western Growers companies that we considered to be leaders in irrigation efficiency. In that study, the average DU was just over 81 percent, which is considered good but more than nine points below the DU expected of a new system. We all know that the water, energy, fertilizer needed to produce a crop increases dramatically with the degradation of uniformity. AGH20 put numbers to this in a recent presentation to the California Agricultural Irrigation Association (CAIA) (see chart below). The AGH2O example: if a grower is attempting to apply three acre-feet of water to all parts of an 80 acre field at 85 percent efficiency, he would apply 17 pounds of fertilizer per acre, 17 acre feet of water and (assuming energy is $0.18/kwh) use $5 dollars per acre in energy costs. If efficiency drops to 80 percent, the costs escalate dramatically and with the same assumptions results in 35lb/acre fertilizer, 33 acre feet of water and $15/acre in energy costs. As goes your distribution uniformity, so goes your money—out the window.
But it doesn’t stop with just throwing money away on fertilizer, water and energy—Charles Burt (Chairman – Irrigation Training and Research Center at Cal Poly San Luis Obispo) says “approximately 55 percent of crop non-uniformity is caused by irrigation distribution uniformity” which underscores the notion that yield is directly influenced by DU as well. The effects of poor DU cascade into and contribute to other problems such as nitrate and ag chem discharge which are bringing regulatory regimes and penalties forward for growers in different parts of California. It is a simple and basic issue that often goes unnoticed. In fact, AGH2O estimates just under 60 percent of farms have actually had their irrigation systems evaluated for uniformity and that the biggest barrier to making improvements to reduce energy use and conserve water was that “investigating improvements was not a priority.”
While Western Growers’ mission is to help our members improve their competitiveness and profitability, at the Western Growers Center for Innovation and Technology we are likewise committed to assisting members to produce more food with fewer inputs. Encouraging members to investigate the performance of their irrigation systems as evidenced by uniformity will help to address those objectives. There are many technologies that will help with water management but they have to stand atop a well performing system.
Author’s Note: There are a lot of things I could write about in the Science and Tech Corner in Western Grower & Shipper and I would welcome input from readers on topics that might be of interest to you.
The following reports can be found online.
“Management of Agricultural Energy and Water Use”
Management of Agricultural Energy and Water Use with Access to Improved Data
“Irrigation Systems Evaluations”
https://www.wga.com/resources/irrigation-systems-evaluations
