Courtesy of R. Troy Peters
Irrigation engineer R. Troy Peters credits his summer job as a teen-ager in arid southeastern Idaho for guiding his career path.
“I grew up irrigating for my uncle every summer in the Magic Valley in Idaho and loved it,” said Peters, professor of irrigation engineering at Washington State University.
“I saw first-hand the value of it. I loved agriculture and I loved engineering, so irrigation engineering was a great meld of those.”
Based at the Irrigated Agriculture Research and Extension Center in Prosser since 2006, Peters has researched innovative irrigation projects dealing with deficit irrigation, water hydraulics, scheduling and management, automation, water quality, and crop water use estimation.
In some cases, crops flourish with a little less water, not more.
To help orchard owners, farmers, and ranchers decide when and how much to irrigate, he developed a free smartphone application, called the Irrigation Scheduler Mobile, in 2012.
The online irrigation scheduling tool also operates as a web page and is integrated with AgWeatherNet and AgriMet, providing daily crop water use estimates and rainfall data.
“Along with farmers, some lawn and garden businesses have started using it,” he said. “A lot of people have learned it’s OK to turn off the water once in a while, especially in spring and fall, with the reassurance their crops will be fine.”
One crop that can withstand deficit irrigation is native spearmint.
“Up to a 60 percent irrigation deficit, no matter the timing, can save water while still maintaining oil yields and quality similar to fully irrigated plants,” he said.
Peters has also been in the forefront of research concerning the reduction of water usage through adjusting the height of sprinklers on crops.
“When sprinklers interact with crops more, you get better yields,” he said of two application types.
Low Energy Precision Application — known by the acronym LEPA — is a modification of the sprinkler configuration on center pivots that dribbles water onto the soil from a low elevation, about 12-18 inches from the soil surface, at low pressure.
Low Elevation Spray Application — known as LESA — uses suspended sprinkler heads, which spread the water out a little more and reduces runoff compared to LEPA.
“It’s more versatile than LEPA with a variety of crops, row orientations and tillage systems.”
Other innovations include using drone imagery to identify water stress areas in fields and automatically adjusting water flows.
Based on the imagery, adjustments can be made with automatic prescription rate generation software to control movement of pivots and provide uniform water coverage.
“Pumps with variable frequency drives are gaining popularity, too, because flows are automatically adjusted,” he said. “They save energy and make life easier for farmers because they no longer have to go to a field to make adjustments to the pump.”
In some areas, cost sharing to convert to innovative irrigation systems is available.
Peters suggested farmers contact organizations including local electric utilities, the Natural Resources Conservation Service and Bonneville Power Administration to learn about potential cost-sharing programs.
R. Troy Peters
Education: B.A. in manufacturing engineering, 1997 Brigham Young University; Ph.D. in irrigation engineering, 2003 Utah State University
Author: Authored or co-authored more than 40 peer-reviewed articles
Family: Wife and six children ages 9 to 23
Hobbies: At his small hobby farm, he says he loves “to read and mess with various technologies in my basement.”