The Influence of Land Cover on Drinking Water Quality and Treatment Cost

Abstract

Abstract Sears, Alexandra. Master of Environmental Assessment. The Influence of Land Cover on Drinking Water Quality and Treatment Cost.

There is significant evidence that land cover is correlated with water quality. There is a lack of evidence however, examining the specific connection between forested land and drinking water quality. National datasets with information on land cover, drinking water intakes and their watersheds, drinking water contaminants, and drinking water treatment cost were used to assess the correlation between forests and drinking water quality. The particular databases were selected because of their national coverage and because they could be linked directly to a drinking water watershed. For each watershed, the percentage of forest cover was correlated with the drinking water contaminant and treatment cost data. The results are highly inconclusive and show no overall trends. The correlation coefficients averaged 0.0698 which rules out rejecting the null hypothesis that there is not a connection between forest cover and drinking water quality. EPA Region 8 (the mountain west) was the most highly correlated region in the country. The correlation between agricultural, urban, and impervious land cover and drinking water quality in that region was no more significant than that of forest cover. Because of the quality of the data utilized, these results should not deter future investigations into similar topics. Knowing how forests and other land cover types affect drinking water quality could influence future land planning measures that lead to a reduction in both the contaminants in drinking water as well as a reduction in the additional cost of treatment related to increased pollutants in the water. More research is needed in this area to determine the influence of land cover on drinking water quality.