Nutrient flushes in stormwater runoff from developing catchments in an upper piedmont watershed

Results from this study revealed that nutrient export from actively developing catchments often was affected more by climatic variation than by degree of land disturbance. However, land disturbance tended to increase the rate at which nitrogen and phosphorous were exported from the catchments and often resulted in first flushes for both total dissolved nitrogen (TDN) and nitrate relative to the flow. Development also impacted the characteristics of organic matter exported during storm events by lowering the aromatic fraction of organic carbon in the stream during the periods of highest storm flows. Evidence of this was based on observed relationships between the specific ultraviolet absorbance measured at 254 nm (SUVA254) and the storm flow during periods of development for each catchment. © 2008 American Water Works Association.