Rhenium (Re) is one of the rarest elements on Earth, however, it is critical for various technological applications. Unfortunately, due to its typically very low concentrations, much of the fundamental biogeochemical behaviour of Re remains poorly understood. Recent work has identified an enrichment of Re in a municipal wastewater treatment plant (WWTP) that discharges to a tributary of Lake Ontario. The Re enrichment is suspected to originate from a metal recycling facility within the sewershed of the WWTP. Surface waters and surface sediments were collected in 2024 and 2025 along a 5km transect of the discharge-receiving river (NR), and a creek (SC) near the metal recycling facility. Aqueous concentrations in NR increase downstream of the WWTP discharge point, measuring up to 0.06 µg/L, contrasting with sediment concentrations, which peak at 45 µg/kg near the discharge point. This is likely due to a change in speciation, i.e., from particulate to dissolved forms of Re downstream of the discharge point. While a point-source of discharge has yet to be identified for SC, concentrations of Re are highest, up to 0.79 µg/L in aqueous samples and 6.3 µg/kg in sediments where the tributary is nearest to the metal recycling facility. I will present the behaviour and mobility of Re in these contrasting aqueous environments, including partitioning between solid and aqueous phases, as well as relationships between Re and other elements of interest to identify potential controls on Re behaviour in the natural environment.