Bushfires can change the concentration and chemistry of organic matter in and on the soil. Moreover, the loss of vegetation caused by fires coupled with post-fire rain can increase erosion rates, annual river flow, and, consequently, stream and estuarine contamination. Although bushfires are expected to increase in frequency, intensity, and scale, there is a lack of knowledge on the effects of bushfires on aquatic systems. We assessed the impacts of the 2019-2020 Black Summer Bushfire on 6 waterways (Clyde, Moruya, Hastings, Shoalhaven, Karuah, and Georges) in NSW, Australia. The estuaries had different fire intensities and catchment burnt areas and were surveyed 1, 6, and 12 months after the fires. At each waterway, sediment samples were collected from the lower and upper estuary as well as the freshwater section. We assessed changes in the concentrations of phosphorus and nitrogen, different forms of organic carbon (total carbon, total organic carbon, pyrogenic carbon), chlorophyll-a, and metals. Preliminary data suggests that the impact of bushfires on waterways can be highly dependent on the characteristics of the estuaries. It is likely therefore that management needs to be done at the estuary level and that impacts should therefore be assessed on a case-by-case basis.