Survival of fecal indicator bacteria in a subarctic Alaskan river was studied during the winter of 1969-70 when there was total ice cover and the water temperature was 0 deg C. Most of the domestic pollution entered the river from one source. Since no additional pollution entered downstream from this source, an uninterrupted study covering 7 days of flow (210 river miles) was possible. Nine sample stations were established to obtain total coliform, fecal coliform, enterococcus and water chemistry data. Samples were collected four to eight times from each station during the 2-week period of data collection, and a discharge measurement was made at each station during the same period. Bacteria survival was examined with and without consideration for the effect of dilution. After 7 days flow time, total coliforms were reduced to 3.2-6.5 percent of the initial count, fecal coliforms to 2.1-4.2 percent, and the enterococci to 18.1-37.3 percent depending on dilution consideration.