Addressing today’s water challenges & supporting tomorrow’s water users

“From the food on our tables to the green spaces we enjoy, irrigation sustains our society,” notes Allan Andales, PhD, professor of irrigation and water science at Colorado State University and principal investigator of the Irrigation Innovation Consortium. IIC supports collaborative research projects focused on accelerating the development and adoption of water and energy-efficient tools, technologies and management strategies applicable in agricultural, landscape and/or urban settings.

Generous financial support from the Foundation for Food and Agriculture Research helps fund IIC projects. Teams pitch their proposals in response to an annual call from IIC, and their projects are subsequently vetted and selected by the group’s Technical Research Steering Committee and Executive Committee. IIC prioritizes multi-institution projects, and all IIC projects must involve both industry and academic partners. In the future, IIC plans to further refine its pitch approach and will likely adjust its call for projects to prioritize research that can help address gaps and vulnerabilities made clearer in the wake of the COVID-19 pandemic to benefit water users and the irrigation sector.

Since its inception in April 2018, IIC has allocated a little over $1 million of FFAR funding to support 14 research projects. Additional nonfederal contributions of funding, equipment, expertise and other resources provided by industry partners, universities and others have more than doubled the FFAR investment.

Since April 2018, IIC has allocated a little over $1 million of FFAR funding to support 14 research projects.

“IIC harnesses the scientific, engineering and business ingenuity of the private and public sectors to advance water- and energy-efficient technologies and solutions available to end users who are managing limited water resources,” says Andales. In addition to IIC’s FFAR-funded project portfolio, the collective expertise resulting from IIC’s formation has led to the initiation of several other projects that were able to leverage other resources to support their work.

The following are highlights and outcomes from a few IIC-supported projects.

• Project – Underground Wireless Networks for Soil Moisture Sensing and Irrigation Water Management
• Goal – To provide affordable, real-time soil moisture data for irrigation scheduling and system control across space and time in different settings
• Partners – Colorado State University, Kansas State University, The Toro Company, the United States Golf Association

Irrigation management decisions hinge on having accurate knowledge of the root zone’s soil water balance and forecasting how that will change. Deploying commercial sensors capable of providing automated, continuous soil water measurements and remotely delivering that information to the cloud, however, is expensive to do at scale. In field crop agriculture, the installation of high-density sensor networks can result in an array of above-ground obstacles — antennas, solar panels and other hardware — that can require removal and reinstallation each season or for certain field operations, increasing costs and creating logistical headaches.

To take advantage of recent developments in low-cost wireless modules, 3-D printing and advances in Internet of Things connectivity, a Colorado State University-based team set out to explore the potential of managing irrigation using a permanently buried wireless, battery-powered sensor network (see fig. 1).

In this proof-of-concept study, the team designed, built, tested and calibrated multiple low-cost soil moisture sensor prototypes ranging in cost from $3-$40 each, which demonstrated accuracy, precision and sensitivity comparable to $120 research-grade sensors (see fig. 2). The sensors were deployed in a variety of settings and soil types (one corn field, two residential lawns and a commercial golf course) and coupled with custom-built IoT carrier boards to upload soil moisture data to the cloud using cellular and Wi-Fi gateways.

The team is currently working on additional testing and sensor design efforts to lower sensor costs without sacrificing their accuracy, along with creative applications of these sensors. “We’ve got a lot planned.” says Jay Ham, PhD, professor of environmental physics and micrometeorology at Colorado State University, and principal investigator of this project. “For example, we’re looking at ways to monitor nutrient and sediment runoff into surface water, a water quality tie-in important for conventional corn production, for dairy systems, in organic agriculture and more.”

• Project – Advancing Development of the Parallel 41 Flux Network to Support Real-Time Evapotranspiration Estimates and Monitoring Using Remote Sensing
• Goal – To expand a multistate network of eddy covariance flux towers that provide real-time evapotranspiration estimates used by farmers and other stakeholders
• Partners – University of Nebraska-Lincoln, Kansas State University, The Climate Corporation, LI-COR Biosciences, RealmFive

The Parallel 41 Network project consists of several latest generation smart eddy covariance flux towers located across the midwestern United States that provide quality-controlled, gap-filled and continuously measured ET, daily reference ET, daily crop coefficient and cumulative measured ET during the growing season. This valuable information can be used by farmers and others to measure crop water use, schedule irrigations, assess plant water stress, monitor drought and calculate water balance and productivity. The project has fostered and expanded collaborative discussion with power companies involved in monitoring energy use and many other groups, including Nebraska’s Natural Resources Districts, which are interested in supporting improvements in irrigation efficiency and water conservation (see fig. 3).

In 2020, network expansion of five new towers will help fill in gaps in spatial coverage, making it possible to monitor additional crops and naturally vegetated surfaces in Nebraska, Iowa, Colorado, Kansas and Texas, providing important spatial information for water balance estimation and recharge within different watersheds and land use contexts.

This flux tower data is being used to verify the accuracy of datasets generated by the Global Daily Evapo-Transpiration project, known as GloDET, that runs the U.S. Department of Agriculture-Agricultural Research Service’s ALEXI two-source energy balance model. The data is also being used in field trials for irrigation scheduling to validate output and improve predictions from a model being used to support a farmer-friendly smartphone and online app being developed by the team.

• Project – Development of a Low-Pressure and Low-Flow Water and Energy Efficiency Media Filtration System
• Goal – To develop a prototype filter which will be more water efficient and operate on lower pressures
• Partners – California State University, Fresno and Perigo LLC

Sand media filtration in agricultural irrigation systems typically involves the use of tanks that require large amounts of pressure and water to sufficiently filter out and discharge contaminants. The team working on this project set out to develop a prototype low-pressure media filter and compare its functionality to that of several off-the-shelf filtration devices.

“In agricultural settings in places like California, where we have high water and energy costs, it is costly to pump thousands of gallons of water through a 40-50 psi system,” says Kaomine Vang, project lead and project manager at California State University, Fresno’s Center for Irrigation Technology. “Typical system pressures can be excessive and destructive for producers using drip irrigation, with drip emitters configured to perform at much lower pressures — 14 psi or less. If producers can use smaller pumps and reduce the pressure in their systems, this could lead to significant cost and water savings.”

• Project – Irrigation Pumping Plant Performance Calculator
• Goal – To develop a calculator tool to help agricultural irrigators assess center pivot pumping plant performance and water use efficiency
• Partners – The Electric Power Research Institute, Hydraulic Institute, IIC partners at University of Nebraska-Lincoln, Colorado State University, Kansas State University and Tri-State G&T

This project, funded by Tri-State G&T through the Electric Power Research Institute, was a partnership-driven spinoff project made possible through the connections and expertise leveraged through the IIC network.

“You can have a perfectly functioning pivot system but lose money if your pumps are inefficient,” says Joel Schneekloth, Water Resources Specialist at Colorado State University, lead developer of the free, spreadsheet-based calculator tool, along with Kansas-based consultant Lee Wheeler, who performed center pivot system audits as part of this project. “The opposite is also true: Your pumps could be fine, but if your center pivot delivery system isn’t optimized, with regard to system pressure or irrigation application uniformity, this inefficiency will add to your costs. The point of the calculator tool is to help irrigators tie these two elements together so they can see which areas may need improvements or upgrades and take the necessary steps to save money,” he says.

This irrigation and energy efficiency calculator tool was released in early 2020. The inaugural Colorado Master Irrigator class of 22 producers farming in northeastern Colorado’s Republican River Basin were provided a training session on using the calculator as part of a day-long session focused on evaluating and improving overall center pivot system performance.

This free, spreadsheet-based calculator is available for download along with other resources for how to use the tool.

Two industry-led pitches were among new projects selected for 2020.

• Project – Economic Impact Study of the Irrigation Industry
• Goal – To update and expand understanding of the irrigation equipment and services industry’s economic impact
• Partners – Irrigation Association, Headwaters Corporation and IIC’s five partner universities (CSU, KSU, Fresno State, Texas A&M, UNL)

• Project – Connecting Field-Scale Performance to Watershed Health
• Goal – To assist the Twin Platte Natural Resource District by providing detailed electrical and water use data to support the TPNRD Data Collection/Water Saving program
• Partners – Nebraska Water Balance Alliance, University of Nebraska-Lincoln, Grower’s Information Services Cooperative, Olsson Engineering and Twin Platte Natural Resources District

Amy Kremen is the operations manager for the Irrigation Innovation Consortium. For a full list of IIC projects, go to www.irrigationinnovation.org.