1. Simulation of Hydrodynamics and Solute Transport in the Suwannee River Estuary, Florida Jerad Bales U.S. Geological Survey Raleigh, NC

2. Study Objectives Characterize hydrologic and salinity conditions in Suwannee River Estuary Develop, calibrate, and document 3-dimensional unsteady flow and salt transport model. Provide tool for further applications in Suwannee River Estuary and offshore.

3. Continuous Data Collection in Estuary Flow Salinity Salinity Water Level Water Level Salinity Water Level 3 km offshore

4. 0.35 in 2000 compared to 0.45 in 1955 0.27 in 2000 compared to 0.25 in 1955 Flows During Data-Collection Period

6. Suwannee River Estuary Net Flows

7. Buoy #1W4 G1 River Fork E6 W1W6W7 W8 WP WM W5 7/27/00 10:40 – 11:33

8. Buoy #1W4 G1 River Fork E6 W1W6W7 W8 WP WM W5 7/27/00 18:35 – 19:54

9. Suwannee River Estuary Model: A Salinity Prediction Tool How can the effects of changes in river flow be separated from all of the other factors affecting salinity in the Suwannee?How can the effects of changes in river flow be separated from all of the other factors affecting salinity in the Suwannee?  Data--no experiments --natural variability is great --natural variability is great  Statistical techniques--many factors  Computer model--captures most relevant natural processes. natural processes.

10. Computational Grid and Boundaries Upstream boundary: AGR Measured flow, zero salinity Ocean boundary: ~20 km Tides from Cedar Key, Salinity = 35 psu Depth = 8-9 meters Tidal boundary: Cedar Key Tides from Cedar Key; Estimated constant salinity Tidal boundary: Horseshoe Pt. Tides from Cedar Key; Estimated constant salinity

11. Some Results

12. Opportunities and Needs Opportunities with existing modelOpportunities with existing model  Evaluate effects of flow changes on salinity distribution (time and space) in estuary and offshore.  Simulate movement of neutrally buoyant material (perhaps larvae?) NeedsNeeds  Increased spatial resolution near shore, including tidal creeks, marshes, and offshore reefs.  Ground water inputs.  Better seaward salinity boundary condition  Nutrient transport.

13. For Additional Information Jerad Bales U.S. Geological Survey jdbales@usgs.gov 919-571-4048

15. Data Collection StreamflowStreamflow WindWind Water LevelWater Level SalinitySalinity VelocityVelocity BathymetryBathymetry

17. Calculation of Net Freshwater Flow at East Pass

18. Flowdistribution on falling tide

19. Flowdistribution on rising tide

20. EFDC--Rationale for Selection Scientifically robust.Scientifically robust. Public domain--available to SRWMD.Public domain--available to SRWMD. Good documentation.Good documentation. Supported by EPA.Supported by EPA. Used successfully by SJRWMD and SFWMD.Used successfully by SJRWMD and SFWMD. Water-quality simulation capabilities.Water-quality simulation capabilities.