“…Accessed October 1, 2019, https://www.usgs.gov/nathydro) provides the most comprehensive classification of perennial, intermittent, and ephemeral streams (Nadeau and Rains 2007). NHD is used extensively for cartography, study design, monitoring, and modeling at local, regional, and national extents (Stoddard et al 2005; Sheng et al 2007; Stanislawski 2009; Hill et al 2016; Isaak et al 2016; USEPA 2016; Macfarlane et al 2017), and such applications frequently use the NHD stream permanence classifications (SPC; i.e., NHD “hydrographic categories” of perennial, intermittent, and ephemeral) (Roy et al 2009; Benstead and Leigh 2012). Comparison of NHD SPC to non‐NHD, in situ streamflow observations (hereafter referred to as NNO) indicate that misclassification of stream class by the NHD can be an issue, particularly for headwater streams (Nadeau and Rains 2007; Caruso and Haynes 2011; Fritz et al 2013; Nadeau et al 2015).…”