In February of 2017, the hillside behind Cal Poly’s Fremont Hall became unstable during a record-setting rainfall season. Shallow, perched groundwater, in conjunction with saturated soil from heavy rainfall, weakened the slope directly behind the hill. This caused the slope to slump at the toe of the 600-foot tall hillside, opening fissures, tipping trees, and sliding a mass of soil against the dorm.
Cal Poly retained Cannon to provide survey and civil engineering services for repair and mitigation of the unstable slope. Cannon’s work, teamed with the geotechnical engineer, Earth Systems, included winterization plans for erosion control, upslope surface and subsurface drain system plans to divert water away from the slide, and grading plans for installation of a new earthen buttress at the toe of slope. The preliminary buttress design alternative was not economically viable, and the university is currently exploring other stabilization methods. The dorm will remain closed until the slope has been permanently stabilized.Back to Service
California Polytechnic State University, San Luis Obispo, California