A comparison of false positive Escherichia coli in surface waters using two methods for enumeration

Surface water samples were analyzed for comparison of the mEndo LES total c oliform and the FC fecal coliform methods for yielding positive results for Escherichia coil. Marked differences were found in the fluorescence of col onies producing the required blue halo versus colonies that fluoresced with out the halo. Overcrowding was found to be an inhibition to finite analysis using total coliform analyses. No difference was found comparing wastewate rs containing traces of already treated domestic wastewater and surface wat ers from bayous or estuaries.