An Interdisciplinary Study of Water Quality in the Galapagos Islands (2014)
Undergraduates: Katie Overbey, Shannon Steel, Billy Gerhard
Faculty Advisor: Jill Stewart
Department: Environmental Science
Tourism and residential population growth may compromise human and ecosystem health in the Gal¿pagos Islands, but human impacts are not well understood. This research provided a baseline characterization of water quality on one of the inhabited islands of the Gal¿pagos, named San Crist¿bal. Tap water was analyzed for Escherichia coli and total coliforms using the IDEXX Colilert-18 kit and Enterococcus levels in recreational water were measured using the IDEXX Enterolert kit. Bacterial concentrations were geo-located and mapped to compare locations of contamination, known water infrastructure, and different types of human activity. For drinking water, lower levels of contamination were observed at individual houses than was observed at the source water and the water treatment plant. This reflects the fact that treatment of drinking water was displaced to the households as a result of construction at the treatment plant. Levels of Enterococcus in recreational water were compared between beaches with different types of human usage to better understand the impact of human activities on water quality. These results revealed higher Enterococcus concentrations near sites subjected to wastewater discharge or urbanization. This research provides insight into how humans impact their environment in an area where economic and developmental demands compete with environmental and public health concerns.