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Table 1 A summary how soil burn severity maps were prepared, debris flow hazard was identified, and debris flow risk assessed for the Stanislaus Complex and Rim fires

From: Improvement in quantifying debris flow risk for post-wildfire emergency response

  1987 Stanislaus Complex Fire 2013 Rim Fire
Soil burn severity mapping Observer-based visual identification from helicopter and ground-level promontories; modified by random ground-level soil survey Computer processing of satellite imagery comparing pre- and post-fire reflectance; boundaries adjusted based on verification by ground-level soil survey
Identification of debris flow hazard Use existing debris flow mapping or aerial-photo interpreted mapping of past debris flow occurrence to identify areas of potential debris flows near identified elements-at-risk Empirical debris flow model combining identified probability of occurrence and likelihood of volume class to show hazard for all drainage basins present in the burned area
Assessing debris flow risk Professional judgment using the assumption that debris flows occurrence differed little between burned and unburned areas and resulted from infiltration-triggered failure mobilizing discrete landslide masses Interpreted based on risk assessment formula using modelled hazard probability and recognizes burned-area debris flows are due to runoff-dominated erosion by surface overland flow