Concentration-Streamflow Relationship In The Red River To North Near Grand Forks, North Dakota

For the last 15 years, the nutrient concentrations have fluctuated in both particulate and dis-solved forms. The increasing concentration of sulfate and chloride in the North Great Plain Basin impose threats to water quality in the Basin. During this spring snowmelt season of 2021, water samples were collected three times daily in the Red River at Grand Forks, North Dakota to de-velop a concentration streamflow relationship for sulfate, nitrate, chloride, and fluoride. The 2020-2021 winter was very dry as a result the snowmelt streamflow was very low, the rising limb period was short, but the streamflow increased rapidly from 75 m3/sec to 180 m3/sec in five days then started to decrease. Sulfate concentration showed a response to streamflow during the study period, fluoride concentration was low and fluctuated very little, nitrate concentration was very low during the melt period then started to change over the course study. Chloride concentration remains very high during the rest of the study period. The C-Q relationship indicates a counter-clockwise direction for sulfate. The nitrate concentration was highly variable to discharge which may be attributed to flushing from organic soil. Chloride C-Q relationship showed a counter-clockwise hysteresis relationship. Discharge showed a little influence on fluoride concentration which can be explain by chemostatic behavior