Resiliency Planning: A Risk-Based Approach to Seismic Evaluation for Southern California's Orange County Sanitation District

This paper presents a novel approach to seismic resiliency evaluations that addresses four key facets of such evaluations: 1) integration of geotechnical and structural analyses; 2) adaptation for both buildings and wastewater treatment process structures; 3) development of evaluation procedures to efficiently accommodate a large number of structures; and 4) prioritization of mitigation projects using a risk-based methodology that may be applied to other types of resiliency evaluations. This case study for the Orange County Sanitation District (OCSD) achieved its objective of producing a prioritized listing of the evaluated structures with recommendations to promote seismic resiliency. General “lessons learned” were identified that apply to resiliency studies of this type.