The economy of western Kansas is based on the Ogallala Aquifer. But that ancient underground water supply is being rapidly depleted. The Kansas Water Office is teaming up with forward-looking farmers in an effort to demonstrate that new irrigation technologies can reduce the demand on the aquifer without sacrificing crop yields.
From mid-May through the end of August, a sound is heard almost non-stop in farm fields all across western Kansas. It’s the sound of an irrigation pump pulling water from deep underground to nourish thirsty crops. Tom Willis owns several of these wells.
“Normally, we’d be running about 300 gallons more a minute than what we’re running right now," Willis says. "You can tell, that engine’s hardly running.”
Willis is able to pump this well more slowly because he’s using a relatively new type of irrigation. The generic name for it is mobile drip. The trade name is Dragon Line. Monty Teeter, of Teeter Irrigation in Ulysses, came up with the idea about seven years ago.
“It’s real important to me that we try to save every drop we can," Teeter says. "You know, our motto is ‘making every drop of water count.’”
Dragon Line is based on the center-pivot irrigation system already present in most irrigated fields. But instead of nozzles that spray the water onto the crop from above, this system has bright orange hoses that let out just a trickle of water directly onto the ground between the crop rows. Teeter says a USDA study in the Texas panhandle found that more than half of the irrigation water applied to bare soil simply evaporates.
“So whenever you see a pivot running with dark soil behind it, or wet soil, we’re evaporating that water," he says. "So when you think of all the water that we pump out here in western Kansas, if we're able to save 25 percent of that water, it would be huge. It would make our aquifer last a lot longer.”
Jonathan Aguilar is the K-State Extension Water Resource Engineer at the Experiment Station in Garden City. Tests conducted there last year show the mobile drip system reduced evaporative losses by around 30 percent. Aguilar says test plot results are not conclusive, but he thinks a 20 percent savings would be a conservative figure. What’s more, Aguilar says there was more moisture in the soil after harvest on the mobile drip plot—as much as a one-inch rain would provide.
“That would allow the plants for the next season to promote a deeper root system for the crop to be able to mine that water later on,” he says.
A crop with a deeper root system is less susceptible to drought. Crop consultant Loren Seaman says the Dragon Line system itself appears to encourage deeper root development. He says water from spray irrigation only penetrates three to four inches deep into the soil.
“But you put the Dragon Line out there every 30 inches, and it will penetrate down to 12 to 13 inches," Seaman says. "And every time that penetration is better, your root system is going down further. The plants build a bigger root system.”
But farmers aren’t likely to adopt this technology until they see proof that their crops will do just as well using less water. Tom Willis is hoping to provide that proof on his land 15 miles southwest of Garden City. He’s running four center pivot systems with the Dragon Line system, and four with state-of-the-art spray nozzles. He’ll compare the crop yields over a three year period. Willis says the Dragon Line fields look good so far, but it’s been a very wet year.
“If we have 40 days of 100-degree weather, you might come out here and say, ‘Well, that didn’t work very well.’ We’ll see, but so far you kind of gotta like what you see,” he says.
Willis is one of three western Kansas farmers partnering with the Kansas Water Office on such a test. Water Office Director Tracy Streeter knows this technology won’t stop the depletion of the aquifer, but every little bit helps.
“The approach here is to conserve and extend," Streeter says. "The portions of the Ogallala that are depleting the worst, if we can slow down that rate of decline, we have irrigators that are able to take advantage of the next round of technology because they have water left underground.”
And that means more time before they’re forced to convert to less-profitable dryland farming.