A spatio-temporal assessment framework for assessment of water quality data

Assessment of water quality impairment of streams and water bodies in space and time is essential task of watershed management. This paper presents a conceptually simple framework for analysis of water quality data in space and time to assess the impairment of streams. The assessment framework defines the analyses based on two characteristics, the type of analysis and the level at which the analysis was carried out. Two types of analyses, deterministic and stochastic (statistical) form the major elements of the framework. Four spatial levels were considered during the water quality assessment. The utility of the proposed framework is tested for assessment of pathogen impairment of several streams due to fecal coliform bacteria in south eastern Kentucky. The pathogen impairment identified in streams in this region is mainly attributed to straight pipes and failing septic systems. Fecal coliform data collected by several water quality monitoring agencies are used to assess the impact of existing water quality management projects on regional water quality at four spatial levels. Results suggest that the framework can provide point and regional assessment of water quality of streams, identify the spatial and temporal water quality trends and evaluate the impact of watershed quality improvement projects.