The commercial poultry processing environment plays a significant role in reducing foodborne pathogens and spoilage organisms from poultry products prior to being supplied to consumers. While understanding the microbiological quality of these products is essential, little is known about the microbiota of processing water tanks within the processing plant. Therefore, the goal of this study was to assess the microbiomes of the scalder and chiller tanks during a typical commercial processing d, and determine how bacterial populations, including foodborne pathogens and spoilage organisms, change during the processing day in relation to the bacterial communities as a whole. Additionally, considering this is the first microbiomic analysis of processing tank waters, 2 water sampling methods also were compared. Results of this study show that Proteobacteria and Firmicutes represented over half of the sequences recovered from both tanks at the phylum level, but the microbiomic profiles needed to be analyzed at the genus level to observe more dynamic population shifts. Bacteria known to predominate in the live production environment were found to increase in the scalder tank and gram negative spoilage-related bacteria were found to decrease in the chiller tank throughout the processing day. Directly sampling the scalder water, as compared to analyzing filtered samples, resulted in significantly different microbiomic profiles dominated by Anoxybacillus species. While no sequences related to major foodborne pathogens were found, further sampling collection and processing optimization should provide researchers and the poultry industry a new tool to understand the ecological role of spoilage and pathogenic bacteria within processing tank waters.