Sagittaria fasciculata (Bunched Arrowhead) is an endangered plant known to grow only in Greenville County, SC, and Henderson and Buncombe counties, NC. This study compared the hydrogeochemical characteristics (hydrologic setting, water chemistry, substrate grain size, and organic matter content) of fourteen Bunched Arrowhead sites across Greenville County. All Bunched Arrowhead were found in partially to fully shaded and saturated discharge areas in close proximity to and fed by continuous and consistent groundwater seeps. The plants grew in sandy substrata with highly variable organic matter contents. Surface waters at these sites were shallow, dilute, and acidic (pH 4.5–5.7). However, the degree to which water chemistry influences the plant's growth and survival remains to be determined.