Dissolved oxygen (DO) is an important constituent of stream ecosystems. Fish and most invertebrates rely on high DO concentrations to maintain healthy populations. DO is largely controlled by primary production by autotrophs, exchange with the atmosphere, water temperature (which controls saturation), and consumption by heterotrophic organisms (Odum, 1956). Riverbeds and hyporheic zones harbor extensive surfaces for heterotrophic bacteria. Thus, the process of hydrologic exchange of water and DO between the river and bed contributes indirectly to river DO concentrations as well. In general, the hyporheic zone has been found to be a sink of DO due to heterotrophic respiration (Mulholland et al., 1997). Furthermore, several hyporheic modeling studies have emphasized the importance of hyporheic respiration or DO consumption due to biogeochemical cycling (e.g., De Falco et al., 2018;Marzadri et al., 2016). Empirical evidence at a few sites have demonstrated that hyporheic DO consumption helps facilitate biogeochemical processes such as denitrification (Baker et al., 1999;Zarnetske et al., 2011a). However direct long-term, high-frequency observations of DO concentrations in rivers