“…In glaciated systems, DOC fluxes can be a major source of organic carbon (OC) to the ocean or terminal lakes (Hood et al., 2020; McKnight et al., 1999). Understanding how instream DOC concentration (C) changes with discharge ( q ) can elucidate where and how DOC is generated in the watershed, the relative controls of surface and subsurface (hyporheic) processes (Castro & Hornberger, 1991; Singley et al., 2021), how DOC source dynamics respond to changing watershed conditions (i.e., snowmelt, flooding, irrigation, etc. ; Evans & Davies, 1998; Godsey et al., 2009; Thompson et al., 2011), and whether OC is limited by supply or hydrologic transport (Creed et al., 2015; Thompson et al., 2011; Zarnetske et al., 2018).…”