Date of Award
Bachelor of Arts
This project examined the presence, prevalence and antibiotic resistance of Coliforms (mainly Escherichia coli), Staph/occocus aureus, fecal Streptococcus, andEnterobacteriacae found in the water samples taken from three selected sites on the North Anna, South Anna, and Little Rivers of the Pamunkey River Basin. The diversity and concentration of the microbes isolated from these sites was evaluated in late January and late March allowing for a comparison of the occurrence of microbes at different times and between the different sites. Over the course of two months the concentration of colonies increased based on colony counts from Nutrient agar. The rate of fecal coliforms at the different sites remained low despite increase in the total concentration of coliforms/ml in March that exceeded EPA safe water guidelines. Antibiotic resistance was also evaluated using isolates from all sites and most demonstrated resistance to at least one antibiotic (as defined by growth at antibiotic concentrations greater than 8mg/ml). There were no resistant organisms to chloramphenicol, kanamycin and tetracycline, while penicillin and erythromycin had a resistant organism at every site. The water quality of the Pamunkey River Basin should continue to be monitored based on the evidence of antibiotic resistance and pollution.
McDowell, Christina, "The presence, prevalence and antibiotic resistance of microbes in the Pamunkey River Basin" (2006). Honors Theses. 1062.