Researchers Develop Novel Approach for Quantifying Nitrate Discharge from Groundwater to Streams

Researchers from North Carolina State University have developed a new way to determine the rate at which nitrate pollution will make its way from groundwater into streams. The work has implications for predicting long-term pollution in groundwater-fed streams.
Nitrate pollution, primarily from fertilizer runoff, is one of the major freshwater contaminants in the United States. Additionally, the pollution persists in aquifers – and thus in groundwater – which feed into streams over a period of years or decades.

Measuring the rate of movement, or flux, of nitrate from groundwater into streams is critical to understanding how this pollutant moves through the environment and to assessing the effectiveness of water quality management. However, nitrate flux has traditionally been difficult to measure and since there is no standard method for doing so, it is rarely measured.
David Genereux, professor of hydrogeology at NC State, along with Troy Gilmore, former NC State Ph.D. student, current faculty member at the University of Nebraska and first author of a paper describing the research, wanted to see if there was a reliable way to measure the flux. They developed a new form of aquifer analysis that uses field sampling results to estimate the rate at which nitrate contamination will be flushed from an aquifer into streams in the coming decades.