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Features Drainage Management Systems
Road ditches reduce nutrients in Iowa

May 27, 2019
By The University of Iowa


New research out of the Iowa Nutrient Research Center reveals that road ditches help reduce nitrates and can function as an edge-of-field conservation practice within a watershed.

Based on similar studies in other parts of the country, research engineer Keith Schilling says the team was not surprised to find soil and groundwater conditions within the ditches favorable for denitrification. They were surprised to see the extent of ditches’ processing capacity. Nitrate concentrations decreased an average of 60 percent in subsurface water from upstream to downstream locations in four of the six ditches. “We found this occurring at levels comparable to wetlands constructed to filter nitrate from agricultural drainage,” Schilling says. | READ MORE