The City of Norfolk, Va. was looking to revitalize sections of its shoreline along the Chesapeake Bay. Long term beach management and protection was therefore required. Local waves and currents are the key drivers of the coastal processes, but storm events can result in significant erosion. Previous modelling studies for coastal projects had relied on modelling of offshore measured waves and remote wave data on the Atlantic Coast. RPS was retained to conduct long-term measurements to obtain more accurate data on wave climate using an autonomous wave gauge system. The data was also used for input to numerical modelling for assessment of erosion, shore stabilization solutions, storm protection, and beach nourishment and better design decisions. As long-term performance of the system was a concern, this project allowed not only for useful data to be collected but provided a test of the long-term durability of the instrument.
The data was used to evaluate the wave and current climate along shoreline and to provide input to numerical models for assessment of erosion, shore stabilization solutions, storm protection, beach nourishment projects and better design decisions. The system also provided measured field data to evaluate storm event impacts, was used to aid in the development of Bay Oaks Beach protection and extension to East Ocean View breakwater field.
Long-term Wave Data Measurements in Support of Coastal Studies for the City of Norfolk, VA
City of Norfolk, VA via Moffat Nichol
One of the key uses of wave data was to inform the wave modelling had been done to date and for future model applications. Model predictions had not been useful in coastal structure analysis and design, so it was necessary to design the field program to capture the dynamics of the area for model calibration. Long term performance of the equipment was also of concern, so it was necessary for the system design to take into account the dynamic coastal environment and corrosive nature of seawater deployments.
RPS designed and built a trawl resistant bottom mount wave gauge for deployment offshore. The wave/current system was a Nortek Acoustic Wave and Current (AWAC) meter. The City of Norfolk purchased the equipment and contracted with RPS, to deploy, service, and maintain the instruments, and for data analysis. Subsequent to the QA/QC process, the final data was provided to Moffatt Nichol for their coastal infrastructure design use for City projects.