This study reports on the presence of the bacterium E. coli in agricultural watersheds, which indicates fecal pollution. We examined its survival in soil and its transport in tile drainage and runoff. We also report on the presence of tylosin, an antibiotic administered in swine. E. coli is presently one of two indicator bacteria that EPA uses to assess the potential presence of fecal pathogens. Water quality standards have been issued for E. coli.