This report summarizes a fluvial morphology and sedimentation analysis performed by Stillwater
Sciences in the Sespe Creek watershed—a major tributary to the Santa Clara River in Ventura
County, California—for the purpose of aiding the Ventura County Watershed Protection District
(VCWPD) with their assessment of post-fire sedimentation and flood protection levels in the
lower reaches near the City of Fillmore. This geomorphology-based study is part of a larger
project designed to evaluate the dynamics between hydrologic, hydraulic, and geomorphic
processes and conditions in the watershed which, together, ultimately affect sedimentation in the
lower reaches. The primary charge of this assessment has been to evaluate whether a post-fire
sediment pulse following the 2006 Day Fire has reduced or will reduce the flood protection levels
in the lower reach near the City of Fillmore, which is presently protected from flooding by the
Sespe Creek Levee. Stillwater Sciences was tasked to conduct the watershed geomorphology
(i.e., fluvial morphology and sedimentation) assessment from a historical (baseline) and
contemporary (post-fire) perspective.