New Mexico State University professor and Turfgrass Extension specialist Dr. Bernd Leinauer is leading the charge on two studies.
Subsurface drip irrigation is not a new concept for turfgrass - Dr. Bernd Leinauer estimates it's been around for at least 30 years, even longer when you look at usage in production agriculture. But recently, there has been an uptick in its popularity for turfgrass in particular.
"We've seen quite a substantial increase in the number of questions and the people who want to know about it," said Leinauer. He noted that the latest water ordinance in drought-stricken California was the first to mandate subsurface drip irrigation for certain turf areas. Subsurface drip irrigation can be installed on an area that hasn't received grass yet as well as retrofitted to an existing turf area.
"When you look at agriculture, subsurface drip has been around and documented so many benefits - you have greater water use efficiency, better yield on less water, and better crop quality," he explained. "In general it surprises us that it took so long for subsurface drip to gain ground in turf."
New Mexico State University's Turfgrass Extension program, where Dr. Leinauer is a professor and turfgrass specialist, is in the midst of conducting two studies to determine if subsurface drip irrigation is suitable for public, high-traffic turfgrass areas.
The first is at The Club at Las Campanas in Santa Fe. The sprinkler systems in the golf course's tee boxes had excessive overspray, going beyond turf areas to cause unwanted vegetation growth around them. Of nine tee boxes at the golf course, three were left alone. Three had Toro subsurface drip irrigation systems installed, and the final three had a subsurface drip irrigation system from another manufacturer. All nine were equipped with water meters.
"We'll monitor water use very closely over the next two years," said Leinauer. "We'll also survey golfers to find out whether they notice if the tee boxes are being irrigated differently, and we'll talk to the superintendent to find out what it means maintenance-wise."
"Hopefully after two years we'll have a good data set to document that subsurface drip uses more or less water," he explained. "Our working hypothesis is it uses less water based on acreage." That is because the subsurface drip system allows uniform watering of only the areas that need it.
The golf course project was in part funded by the U.S. Golf Association as well as both irrigation manufacturers, who donated the materials for the installation.
The second study began in December 2016 with the installation of a drip irrigation system on half of the turf at Paradise Meadows Park in Albuquerque.
"The park project is intended to find out if we can scale up the areas," Leinauer said. "Hopefully we can show that subsurface drip is a viable alternative also for larger areas."
The park also receives more traffic than the tees, including all sorts of sports activities from kids and families that live there.
Water meters have been installed on both sides of the turfgrass area to track water usage. "We put everything in and now we just have to wait and collect the data," Leinauer concluded.