Cedar Key Sea Groin Design

Cedar Key is a historic working waterfront community on Florida’s Nature Coast facing accelerated sea level rise and shoreline erosion. These impacts threaten both the town’s coastal edge and the industries that define it, including clam farming, fisheries and tourism. Protecting the shoreline is critical to preserving local livelihoods, public access and cultural heritage.

Halff provided engineering design, environmental, and permitting services for the Cedar Key ShOREs (Shoreline Options for Resilience and Equity) Phase II project, which focuses on the implementation of nature-based solutions for shoreline protection in Cedar Key, Florida.

Building on the community-driven planning completed by University of Florida (UF), Halff designed a shore-perpendicular groin structure that integrates a living shoreline — also known as Sea Groin — to protect the G Street shoreline, support ecological function, enhance coastal resilience, and create safe public access. Halff engineers and environmental scientists coordinated with permitting agencies such as USACE and FDEP to develop construction drawings and technical specifications. Halff’s design incorporates stakeholder feedback to improve stakeholder and community buy-in.

UF staff completed hydrodynamic modeling of waves and sediment transport to assess forcing of the physical environment. UF also measured hydrodynamic current and wave data from hurricanes Idalia (2023) and Helene (2024) which informed engineering design.

Halff also developed near permit-ready site plans for seven shoreline protection strategies outlined in the Cedar Key Living Shoreline Master Plan, ensuring that these designs can be readily adapted by property owners and the City. Shoreline protection designs include various types of living shorelines and habitat creation measures that feature vegetation, geosynthetic bag systems, oyster bags, and reef balls. The plan also includes riprap and articulated concrete solutions for heavily exposed, steep slopes.