Waste Not, Want Not: Reusing Water
Madison Farms headquarters looks a bit like a traffic control center, with banks of computer monitors tracking everything that is happening on 56
irrigation circles and beyond. “We grow eight different crops on this farm,” said Kent Madison, owner of Madison Farms. “That’s not because we think it might be fun to grow alfalfa or snap peas, but because this mix of crops allows us to spread out our water use throughout the year.”
Nineteen percent of Madison Farms’ water comes from the Lamb-Weston potato processing plant in Hermiston.
“We receive 788,000 pounds of nitrogen along with the water,” Madison said. “To Lamb-Weston, that was a 788,000-pound problem they had to dispose of. To us, it’s fertilizer we don’t have to buy.” Madison Farms takes the facility’s treated water year round, reducing to zero Lamb-Weston’s reuse discharge to groundwater.
Don Horneck, OSU Extension horticulturist at the Hermiston Agricultural Research and Extension Center, is working with Madison Farms, Lamb-Weston, and other irrigators and industries in Hermiston and Morrow to explore options for water reuse.
Oregon’s Department of Environmental Quality defines water reuse as “the use of water that has already been used once and has been treated to a level that allows it to be used for another purpose while still being protective of the environment and human health.”
Processing potatoes takes a lot of water. Each day, used water flows from the processing plant to a facility Lamb-Weston built to filter and clean all their potato water. They retrieve chunks of potato for cattle feed and extract potato starch to be refined and sold. The remaining water, all two million gallons a day, is measured to determine levels of nitrogen and other nutrients before it goes to Madison Farms, channeled directly through five miles of pipes to center pivots irrigating field corn, alfalfa, and other crops.
It’s a huge bookkeeping job to keep track of nutrient loads and irrigation scheduling, according to Scott Lewis, an engineer at Lamb-Weston. His facility provides Madison Farms with a weekly report on the nutrients in the water. That information, combined with soil moisture, temperature, and nitrogen measures from each of his fields, helps Madison plan his water management.
We walk out to a center pivot field, 125 acres of corn irrigated with treated reuse water from the potato processing plant. The corn is lush. The soils in this part of the Columbia Basin are sandy and relatively low in nutrients, Horneck explained. This poses challenges to the quality of groundwater in the upper alluvial layers and to the quantity of water in the lower basalt layers. And since 1990, when a Groundwater Management Area was established in the lower Umatilla Basin, people have been looking for ways to use less water and keep groundwater uncontaminated.
“Water and nutrients are too expensive to waste,” Madison said. “Reusing water has provided us with an additional source of water to expand our operations. Using water from food processing completes the cycle, conserving water and keeping groundwater uncontaminated.”