Applications of Fluorescence Spectroscopy for Monitoring Water Quality in an Urban Watershed

In an urban watershed anthropogenic influences can cause detrimental effects on the region’s rivers and streams and lead to negative impacts on water quality. Determining the water quality and health of these aquatic ecosystems requires identification of natural and anthropogenic influences and an understanding of the seasonal hydrologic cycle. Dissolved organic carbon (DOC) represents a significant carbon reservoir in all ecosystems and can be used as a means to measure the characteristics and sources of organic matter in aquatic environments. Fluorescence spectroscopy can be used to quantify and characterize a subset of the DOC pool, the colored dissolved organic matter (CDOM), which can absorb and re-emit energy as fluorescence. This study utilizes fluorescence spectroscopy to characterize organic carbon in the Portland, Oregon urban watershed temporally and spatially and to trace the anthropogenic signature found in wastewater effluent associated with treatment plants.