Nebraska’s nitrate problem is leading academics, entrepreneurs and farmers to ask: Can we science our way out of this?
It’s a daunting task. A “humongous” amount of nitrate has already seeped into the vadose zone — the stretch of earth between the surface soil and the groundwater — where it will continue to leach into the water for years to come, said Arindam Malakar, a professor with the Nebraska Water Center and the University of Nebraska-Lincoln’s School of Natural Resources.
Malakar is researching that zone, where nitrate no longer helps crops, but has yet to reach the groundwater that supplies much of the state.
He’s secured a grant from the U.S. Department of Agriculture, and is now in early-stage work observing how nitrate and nitrogen behave and react in that in-between zone.
Understanding that may unlock the possibility of future technology that can reduce nitrate, he said.
New ag technology is already allowing cutting-edge farmers to lower the amount of nitrogen they put into the soil and the groundwater.
New additives placed into nitrogen make it less likely to leach into the water supply, said Don Batie, a Lexington-area farmer who serves on the Nebraska Natural Resources Commission.
Real-time sensors also allow farmers who use that technology to know exactly how much fertilizer they should put on various parts of their cornfields — eliminating guesswork that often leads to fertilizer overuse. The real-time sensor technology is expensive, but the price is likely to come down over time, Batie said.
This year, Batie used a product that pulled nitrogen out of the air and onto his corn. That means he had to use less commercial fertilizer on those test corn fields.
In the future, the advancements may allow cornfields to grow using large amounts of nitrogen in the air — much like soybeans do — and further curtail the need for fertilizer, Batie said.
Newly developed corn hybrids will also require less nitrogen fertilizer, he said.
“Agriculture has to continue to improve our efficiency,” Batie said. “Many of us feel we have come a long way. But I’m not saying we should celebrate. We have to continue to get better.”
Meanwhile, private sector researchers are exploring better ways to treat high-nitrate water. At Vestal W2O, a Lincoln-based company, a team of scientists is turning to biology — specifically, algae smaller than the eye can see.
When grown in nitrate-laced water, the algae use nitrate to grow, removing it from the water, said Paul Black, a former biochemistry professor at the University of Nebraska-Lincoln, and chief scientific officer at the company. The technique was able to reduce nitrate levels from 250 parts per million down to just 5 parts per million, Black said.
The nitrate taken up by the algae gets converted into protein and biomolecules. The algae can then be filtered out, dried and turned into products such as fertilizer pellets — pellets that can be reused by farmers. The pellets are less likely to taint groundwater.
“The nitrate is there, but it’s going to be rapidly absorbed by the growing plants,” Black said.
The science is sound, he said. But Vestal is running into challenges. An algae-based water treatment system requires specific conditions: The water requires constant stirring and movement. The treatment system needs certain carbon dioxide levels and certain wavelengths of light — researchers found red works best.
Vestal's project is running out of grant money and hasn’t been able to secure more. Black says there’s not enough of a sense of urgency.
“We have a health crisis in the Midwest. That in itself should wake up a lot of people saying, ‘My gosh, this is an urgent situation that has to be taken care of,’” Black said. “It’s going to cost money. How do you define the cost of clean water?”
The Flatwater Free Press is Nebraska’s first independent, nonprofit newsroom focused on investigations and feature stories that matter.
Here’s how to protect yourself from nitrate in Nebraska water
Nebraska’s nitrate problem is serious, experts say. Can we solve it?
Gloss