CSA Ocean Sciences Inc. (CSA), a leading global marine environmental science consulting firm, has announced the completion of a survey to collect data for hydrodynamic model calibration and verification in Nassau Sound, located north of Jacksonville, Florida.

The CSA team measured inshore and offshore water level, tides, current and waves to calibrate and validate a hydrodynamic model. The team installed water level recorders and a wave-enabled Acoustic Doppler Current Profiler (ADCP) and conducted an estuarine water discharge survey to gather the needed data.

Morgan & Eklund, Inc. (M&E), CSA’s sister company, a licensed survey company specializing in hydrographic surveys, teamed with CSA on this project. The project was contracted and managed by Olsen Associates, Inc. (Olsen), an industry leader in coastal engineering and experts in beach restoration projects.

ADCP Current Profile at Ebb Tide

The survey and the subsequent hydrodynamic modeling by Olsen supported sand borrow area development and permitting analyses for the South Amelia Island Shore Stabilization Project. The project is an ongoing engineered beach nourishment project managed by the South Amelia Island Shore Stabilization Association in Nassau County, Florida, and the Florida Park Service.

Vessel Mounted ADCP

“CSA’s estuarine water discharge surveys collected tidal current data as ADCP profiles of current velocity and direction, said Tim Shaw, CSA’s Project Operations Manager. “We conducted ebb and flood tide surveys in a series of transects crossing the South Amelia River, the Nassau River, the Intracoastal Waterway, and the Nassau Sound throat. Tidal prism transects were run continuously over a full tidal cycle across the mouth of Nassau Sound (parallel with the A1A Bridge). The transects were conducted using a vessel mounted ADCP equipped with bottom tracking and integrated with the vessel’s navigation and positioning system,” Mr. Shaw continued.

To ensure survey integrity, M&E established project horizontal and vertical control and took vertical measurements of the instruments twice during the deployment period to identify any potential vertical shifts of the instrumentation.

“The data collection went very well, especially the ADCP work… I think that’s the first time the tidal prism has been calculated like that at this location. The model calibration for prism came out really tight as well.” Said Dr. Albert E. Browder, the Olsen Project Manager.