California Ocean Plan Amendments: Applicability and Requirements for New, Expanded, and Existing Facilities

Although the City of Santa Barbara’s seawater desalination plant and intake are exempt from the Ocean Plan Amendments’ (OPA) requirements, the City has chosen to conduct its subsurface intake (SSI) study using the technical criteria presented in the OPA. This paper presents the OPA’s SSI feasibility analysis requirements and summarizes the SSI feasibility analysis performed in Santa Barbara to serve as a water supply for its existing desalination plant, in accordance with the OPA’s criteria. For the analysis, vertical wells, onshore infiltration galleries, radial collector wells, slant wells, subsurface infiltration galleries, and HDD wells were considered. The study included a literature review, the design basis, coastal/oceanographic hazards identification, a sediment transport analysis, and a hydrogeological assessment. Conceptual designs for each SSI alternative were developed and subjected to an initial screening analysis to evaluate technical feasibility based the OPA’s requirements.