Farmer Solves Water Woes with Subsurface Drip Irrigation

Source:  Blue Mountain Eagle
Written by Scotta Callister
Published June 2, 2015

When Jim Bahrenburg looks across the land he’s worked in the Monument and Kimberly areas, he sees buried treasure.

That treasure isn’t gold, but water.

Drawn from the North Fork John Day River, this water flows through small underground tubes to gradually irrigate blocks of land for crops. Starting on the North Fork Ranch in the Kimberly area, Bahrenburg said he first planted rye to choke out the thistles on what was just a neglected pasture, and then continued the transformation by planting row crops.

Today the land produces corn, onions, beets, peppers, squash and dill.

The key to that abundance is a subsurface irrigation system he first tried four years ago, with a grant from the Oregon Watershed Enhancement Board through the Monument Soil and Water Conservation District.

He got a second grant in 2012, from the Environmental Quality Incentives Program known as EQIP, through the Natural Resources Conservation Service to replace old pumps, install main lines and set up an underground system on 20 acres of land leased from Bansen Farm LLC near Monument, which also grows crops today.

In a region preoccupied with drought and water supply woes, he says, subsurface drip irrigation is a path to more efficient water use, better crop yields, and a more self-sufficient farming economy.

The beginnings

Bahrenburg, who has been farming in Grant County for 44 years, is certified as an organic grower, meaning he can’t use herbicides, pesticides or conventional fertilizers. He said he started looking into the subsurface approach after becoming frustrated by weeds.

“One year I planted 100,000 onion seeds, with above ground sprinklers, and I couldn’t keep up with the pigweed,” he said. “I lost the crop.”

He considered surface drip irrigation, but that didn’t solve the weed problem.

Then he read about work done by Suat Irmak, a University of Nebraska engineer who has developed irrigation systems for water stressed areas worldwide, and was intrigued.

“I hopped on a plane, and what he showed me solved many problems,” Bahrenburg said.

How it works

The subsurface drip irrigation, or SDI, system used by Bahrenburg distributes water through a network of tubing that comes in 1,000 foot rolls, with emitters every 18 inches.

The tubing is set 15 inches beneath the surface, which irrigates the plant roots without the evaporation, runoff and weed germination seen in overhead irrigation. The depth is important, he said, noting a farmer in Idaho went too deep and the system didn’t work. Too shallow, and the tubing may be at risk as the farmer discs or works the soil.

So far, Bahrenburg sees “tremendous water savings.” The water is dispersed at .26 gallons per hour, compared to 3 gallons a minute with surface sprinklers that also lose significant water to evaporation. He notes that on a hot day, an above-ground watering system may lose 20 percent or more to evaporation.

The mission

For Bahrenburg, this is not just about his own crops.

A neighbor, Ted Phelps, also installed an SDI system on 20 acres, bringing the total to 60 acres of SDI fields in that area. Bahrenburg said there also is a 1-acre system at the Malheur Agricultural Research Station in Ontario, and a 3-acre plot on a farm in Milton-Freewater. Azure Standard currently is farming one of the SDI fields in Kimberly.

Bahrenburg cites predictions that SDI and no-till farming will become worldwide solutions by the end of the century, to conserve water, preserve water quality, and manage labor and power costs.

Locally, he sees agriculture and efficient water use as a keys to a sustainable economy and food security for Grant County.

“We have a relatively small population in a large county, a significant national forest, orchards with fruit trees, diversified crops on farms and ranches, with good soils and an important water resource,” he said.

Bahrenburg recalls looking over a field and being struck by the significance of SDI, cover cropping, and no-till planting – “and feeling like I have just now learned how to farm.”