OBJECTIVES: This study aimed to determine the role of drinking water in the transmission of MABS. METHODS: A total of 289 isolates were cultured from respiratory samples (231) and drinking water sources (58) across Queensland, Australia. MEASUREMENTS AND MAIN RESULTS: Whole genome sequences were analysed to identify DCCs and determine relatedness. Half of the isolates (144, 49·8%) clustered with previously described DCCs, of which 30 formed a clade within DCC5. Pangenomic analysis of the water-associated DCC5 clade revealed an enrichment of genes associated with copper resistance. Four instances of plausible epidemiological links were identified between genomically-related clinical and water isolates. CONCLUSIONS: We provide evidence that drinking water is a reservoir for MABS and may be a vector in the chain of MABS infection.