Learning about denitrifying bioreactors drew a good crowd of farmers and landowners from Central Iowa – and beyond – to the Iowa Learning Farms and Prairie Rivers of Iowa field day on Tuesday, July 17th. As a relatively new practice designed to reduce losses of nitrates from tile drained water, the crowd on Tuesday showed a high level of awareness and were eager to learn how bioreactors and other edge of field practices fit in to the Iowa Nutrient Reduction Strategy.
Local landowner Joe Ruetter installed a bioreactor on his farm last fall and has been pleased with the results of reducing nitrate in his tile water.
“We collected a sample a few days ago and the tile water coming in was running about 10-20 ppm of nitrate – well above the safe drinking water standard of 10ppm. At the end of the bioreactor is was 3-5ppm. So I would say the bioreactor is working very well so far.”
Joe also brought up that bioreactors are designed to address nitrate but don’t help with phosphorus so other conservation practices – like no-till and cover crops – are also needed to help reach our goals.
Jace Klein, with Ecosystems Services Exchange, also emphasized the importance of utilizing the right practice in the right place.
“All conservation practices have a place on the landscape. It’s a matter of fitting the right practice in the right location so as to maximize the efficiency and cost effectiveness of the practice,” stated Jace.
In combination with the Conservation Station On The Edge demonstrating the science of denitrification, Jace pointed out the scope to which each practice is capable of treating.
“If you have 40-120 acres next to a stream or creek, a saturated buffer would be the first practice we would explore. If that same sized field doesn’t outlet to a stream, then a bioreactor should be considered. However, if we are looking at multiple connections of tile draining much larger areas the most effective practice to consider would be a wetland,” explained Jace.
By utilizing all the pieces of the puzzle – in-field and edge of field practices – the goals of reducing the losses of nitrogen and phosphorus from our landscape are possible. We have gathered many great resources about edge of field and in-field practices on our website: www.iowalearningfarms.org. You can also visit with your local NRCS office to determine which practices are best suited for your land and discuss cost share opportunities.