Drought pushes the limits of irrigation

 

Most farmers in western Kansas can’t just look to the skies for water to nourish their crops -- they have to dig down to the Ogallala Aquifer to supplement Mother Nature. They use an impressive amount of water, with irrigation often accounting for 85 percent of the water used in the entire state.

“Without irrigation, this ‘Golden Triangle,’ as I’ve heard it referred to, of Dodge City, Garden City and Liberal just wouldn’t be very golden,” said Mark Rude, director of the Southwest Kansas Groundwater Management District.

Rude’s district has more than 10,000 wells irrigating about 1.5 million acres.

The crop circles that dot western Kansas’ landscape aren’t the doing of aliens, but of that vital irrigation system. A long collection of pipes pull water from the rock formation below and supply it to hanging sprinklers that move around farmers’ fields in a circle.

Those center-pivot irrigation systems spread about 500 gallons a minute. Amazing, right? Well, in 2011 it wasn’t enough.

“With the drought, many of the irrigation wells and the farming practices for fields are in somewhat of a deficit irrigation environment,” Rude said. “In other words, they don’t have enough water supply from their groundwater sources to fully supply a crops demand.”

That has forced farmers to re-evaluate how they use their water and where they get it from.

Each well has a yearly limit set by the state, but Rude says that in most years, producers don’t need the full amount. However, more than 1,000 producers have applied for Drought Emergency Term Permits so far this year, which would allow them to go over their allotment.

 

Irrigation is typically a supplement to rainfall – but “typical” didn’t apply this year. The drought forced farmers into action, according to Bruce Reichmuth, manager of Hydro Resources, a well-drilling company in southwest Kansas.

“A year ago at this time we weren’t all that busy,” Reichmuth said. “This year is like night and day from a year ago.”

To be thorough, Reichmuth said, farmers are asking his company to drill up to six test holes to look for more water on their land.

“They want to try and find that best location that will give them the most water for the longest time,” Reichmuth said. Hydro Resources' testing service is booked solid for a couple of months.

Irrigation isn’t cheap. Each five-inch wide test hole costs $3,500. If you decide to move your well after the tests, that’ll set you back another $75,000. Put a new center-pivot system up and that’s $70,000, or more. Thankfully though, Reichmuth says wells often last more than 30 years.

Once you have the water, efficiency in the field is critical, according to Norman Klocke, a Kansas State Extension irrigation engineer. The Ogallala, after all, isn’t unlimited.

“One of our big developments in recent years is to be able to spread that water farther,” Klocke said. Advanced sprinklers distribute bigger droplets, preventing evaporation in the summer heat.

Driving the dirt roads that divide southwest Kansas farmland, Klocke pointed out the streams of naturally cold water falling on the fields.

“Our efficiencies of delivering water are high in our irrigation systems,” Klocke said. “Now, the question is matching up the crops we choose and the amount of land we irrigate with the water supply that we have.”

The Crop Water Allocator program, created by Kansas State, can help optimize water use and answer some of those questions. The software can show farmers how much money they’ll make based on what crops they plant with the water available.

“I’ve got 11 inches of rainfall in here, that’s actually the lowest the model will go,” Klocke said while demonstrating the program. “We decided we need to extend that after this year.”

Klocke says he’ll meet with farmers this winter to discuss their options for 2012.

There’s nothing like a historically bad drought to test the limits of agriculture and make farmers look forward to next year.