Water-quality data for untreated and treated urban stormwater samples and saturated hydraulic conductivity measurements of filter beds for two stormwater filters in Coon Rapids, Minnesota, 2023-2025

This dataset includes water-quality data and saturated hydraulic conductivity based on field measurements of infiltration at two stormwater filters in Coon Rapids, Minnesota. The two filters include: (1) Woodcrest which consists of side-by-side filter beds, one containing an iron-enhanced sand media and the other containing iron-enhanced sand plus biochar, and (2) Epiphany which consists of one filter bed containing iron-enhanced sand plus biochar. To characterize the presence and removal of various pollutants in urban stormwater and removal by filtration, grab samples were collected during or immediately following rain events during 2023-2025. Water samples were analyzed for total phosphorus, orthophosphate, total suspended sediment, E. coli, organophosphate flame retardants (15), nonylphenol and alkylphenols (4), pesticides and pesticide degradants (184), pharmaceuticals and personal care products (57), per- and polyfluoroalkyl substances (PFAS; 33), and tire wear contaminants (2). Water quality properties such as water temperature, dissolved oxygen, specific conductivity, and pH were also measured upon sample collection. Infiltration was measured at 20 locations within each filter bed once during 2024 and measurements were used to calculate saturated hydraulic conductivity.