Fig. 2
Geospatial datasets used to assess the downstream water-quality impacts of the 2022 McKinney rain-on-wildfire event on the main-stem Klamath River, California. The rain-on-wildfire event triggered sediment-laden flooding and post-fire debris flows (PFDFs) in the Vesa and Humbug watersheds, delivering the first flush of fire-scar material to the downstream receiving waters of the Klamath River. Panel (a) shows burned areas for the 2022 McKinney Fire and 2022 Yeti Fire on August 2, 2024, the location of the Seiad monitoring station, and river distances upstream from the Pacific Ocean. Thin blue lines represent tributary channels impacted by the Yeti Fire and McKinney Fire. Red outlines represent wildfire boundaries. Black outlines represent the Vesa and Humbug watersheds that produced sediment-laden flooding and PFDFs. Panel (b) shows burn severity maps43. Panel (c) shows estimates of the minimum predicted PFDF volumes computed using a design storm with a 15 min rainfall intensity of 40 mm/h52. Panel (d) shows maximum rainfall rates on August 2, 2024, at 20:23 PDT computed using NEXRAD 5-6 min rainfall rate estimates measured by the KMAX weather station (NCDC, 2023a). Panel (e) shows 3-h rainfall accumulations on August 2, 2024, between 17:30 and 20:30 PDT, computed from hourly accumulation estimates measured by the KMAX Station (NCDC, 2023a). The highest 3-h rainfall accumulations occurred in Humbug Creek, while the highest rainfall rates, burn severity, and erosion by PFDFs occurred in Vesa Creek. Figure created using ArcGIS Pro (v. 10.6; Esri, Redlands, CA, USA).
