Skip to main content
2025 EWRI Congress Main banner
Final Program


Back

Oral

Hydraulics & Waterways

Understanding the Implications of Hydrodynamics Changes Around Oyster Aquaculture Sites for the Prediction of Fecal Coliform Transport: A Case Study for Ward Creek, North Carolina

Tuesday, May 20, 2025
5:00 PM – 5:15 PM Alaska Daylight Time (AKDT)
Room: Room 2
Abstract Submission: With the rapid expansion of oyster aquaculture in North Carolina, more coastal areas are converting to oyster-growing areas. Floating oyster lease systems (FOLS) are increasingly at risk from fecal coliform contamination, which poses significant public health challenges. Runoff from agricultural fields during rainfall transports fecal coliforms into coastal waters. As more coastal areas are converted for oyster operations, understanding the transport of fecal coliforms around FOLS is crucial for public health and industry sustainability. To address this, a Delft3D hydrodynamic model was developed using bathymetric and tidal data for Ward Creek, North Carolina. This site was selected because it is home to multiple FOLS, which are frequently exposed to high levels of bacterial contamination after relatively moderate rainfall events. The model integrated FOLS using a modified vegetative canopy equation with specific depth-averaged coefficients developed for these types of oyster leases, to accurately simulate the impact on water flow. A Delft3D-WAQ (water and aquatic ecology) module is coupled with the hydrodynamic model and simulated for various fecal coliform concentrations to examine how FOLS alter bacterial transport. Results indicate that fecal coliform exposure duration increases for areas with FOLS, when compared to non-growing areas within Ward Creek, due to velocity dissipation around these systems. The findings of this case study provide a framework for similar models in estuarine environments with FOLS. This integrated numerical modeling approach significantly enhances the ability of aquaculturists and regulatory agencies to safeguard public health in aquaculture-rich estuarine environments by providing a framework for real-time water quality management.

Learning Objectives/Expected Outcome (Optional) :