Spatial Pattern Analysis of Water Quality Levels in Private Household Wells as a Function of Demographic Factors

In Colorado’s San Luis Valley, nearly one third of all residents get their drinking water from wells that are connected to an extensive, shared aquifer.  Since well water does not receive the same protections that regulate municipal water supplies, well users are responsible for safekeeping their own water. In 2009 the Environmental Protection Agency (EPA) helped fund a community collaborative led by the San Luis Valley Ecosystem Council (SLVEC) to examine water quality in selected wells throughout the San Luis Valley, in the upper Rio Grande River watershed in the San Luis Valley of southern Colorado.  This study explores the dataset obtained during this study, comprised of over 162 private wells as part of an environmental justice project.  Our purpose was to examine water quality indicators (e.g., nitrate levels) with respect to potential correlations with demographic features.     Contamination levels in household wells were compared to occupancy status (e.g., rental versus owned), household income, ethnicity information and other demographics via Geographic Information Systems (GIS) software.  A spatial analysis of Census block level demographic data was conducted with data obtained from the US Census, via the American Fact Finder and the New York Times Mapping of America as primary sources.   We anticipate that this study will assist health officials and county health offices to allocate limited funds to certain neighborhoods that may be impacted by low water quality.  Analysis will also reveal how income levels can be correlated with health disparities associated with well water contamination.