publications > scientific investigations report > surface-water and ground-water interactions > figures, tables and equations

Figures

Figure 1. Map showing Central Everglades and adjoining areas, south Florida, showing in (A) locations of Water Conservation Areas (WCA), Everglades Nutrient Removal (ENR) project, and Stormwater Treatment Areas (STA) and showing in (B) generalized hydrogeologic features across Broward County, in the central Everglades, South Florida.

Figure 2. Schematic diagrams of topography, surface-water levels, and ground-water levels in predrainage (A) and present-day (B and C) hydrologic systems.

Figure 3. Research sites, instrumentation, and natural and man-made features in Everglades Nutrient Removal (ENR) project (A) and Water Conservation Area 2A (WCA-2A) (B).

Figure 4. Hydrogeologic cross section B–B' in Water Conservation Area 2A (WCA-2A).

Figure 5. Schematic diagram showing hydrologic fluxes of the South Florida Water Management Model.

Figure 6. Hydraulic conductivities of wetland peat and fresh water marl/sand layers that are transitional to the underlying Surficial aquifer.

Figure 7. Cumulative distributions of vertical fluxes across the peat surface at wetland sites near levees (A), interior sites in Water Conservation Area 2A (WCA-2A) (B), and interior sites in Everglades Nutrient Removal (ENR) project (C).

Figure 8. Magnitude of observed and simulated discharge and recharge fluxes in relation to hydraulic conductivity of peat and distance from levees.

Figure 9. Surface-water levels and vertical fluxes observed at site U3, and precipitation data from near U3.

Figure 10. Estimates of discharge and recharge at selected sites, and time-averaged values of precipitation, evapotranspiration, and surface-water flows.

Figure 11. Locations of wells and piezometers sampled for dissolved radium.

Figure 12. Characteristics of peat soil and underlying fresh water marl and sandy sediment.

Figure 13. Concentrations of dissolved chloride in relation to depth below the peat surface (A), and pore-water ²²⁴Ra activities in relation to chloride concentrations (B).

Figure 14. Pore-water radium activities in relation to depth below peat surface at sites S10C S (A, B), S10C N (C, D), and U3 (E, F).

Figure 15. Vertical fluxes of water based on Darcy-flux calculations and estimated by radium technique (using ²²³Ra ) at site S10C S.

Figure 16. Magnitude of observed and simulated discharge or recharge fluxes at sites in the Everglades Nutrient Removal Project (ENR) and at S10C in Water Conservation Area 2A (WCA-2A).

Figure 17. Maps and schematic diagrams associated with model for tritium transport in Water Conservation Area 2A (WCA-2A).

Figure 18. Mean annual tritium concentrations in precipitation estimated for Miami, Florida.

Figure 19. Sensitivity of the tritium transport model for WCA-2A.

Figure 20. Tritium concentrations in relation to depth of wells for samples collected between September 1997 and September 2001 from 25 monitoring wells in Water Conservation Area 2A (WCA-2A).

Figure 21. Simulated ground-water residence times in relation to measured tritium concentrations in ground water and concentrations of tritium in surface water.

Figure 22. Simulated ground-water residence times in relation to measured tritium concentrations.

Figure 23. Summary of lithology, water exchange fluxes, residence time of ground water and hydrogeochemistry.

Tables

Table 1. Summary of hydrogeologic properties of the Surficial aquifer, central Everglades, south Florida.

Table 2. Calculations of vertical fluxes in WCA-2A.

Table 3. Measured physical properties and hydraulic conductivities of peat and underlying transitional sediments.

Table 4. Vertical fluxes across the peat surface measured at wetland sites over a 5-year period in Water Conservation Area 2A (WCA-2A) and over a 2-year period in Everglades Nutrient Removal (ENR) Project.

Table 5. Calculated radium distribution coefficients in Everglades peat.

Table 6. Pore-water radium activities in Everglades peat and radium fluxes to the surface water.

Table 7. Parameter estimates used in the base simulation run of a tritium transport model.

Table 8. Sensitivity of tritium transport model results due to factor-of-2 changes in input parameters.

Table 9. Ground-water residence times as estimated from analysis of tritium-helium ratios in samples collected during September, 1997.

Table 10. Independent estimates of surface-subsurface water exchange fluxes.

Equations

Equation 1. Mass balance equation for surface water.

Equation 2. Mass balance equation for ground water.

Equation 3. Equation that computes a net flux between surface water and ground water by summing total recharge and discharge.

Equation 4. Governing equation for a hydrogeologic model.

Equation 5. Governing equation for a hydrogeologic model.

Equation 6. Governing equation for a hydrogeologic model.

Equation 7. Simple, linear, sorption isotherm equation, rearranged to solve for the radium distribution coefficient.

Equation 8. As a dissolved ion, radium is transported with pore fluids and its gain or loss near sediment/sediment or sediment/water interfaces can be modeled in saturated sediments as a balance of its production, decay, advection, dispersion, and exchange with particles.

Equation 9. Simplified version of equation 8, solved for the concentration of radium at any depth in the peat. Used when conditions are at steady-state, and in areas where advective fluxes greatly exceed dispersive fluxes.

Equation 10. The steady-state solution to equation 8 for the case where dispersion dominates over advection.

Equation 11a. Equation describing the vertical profile of dissolved radium (for advection).

Equation 11b. Equation describing the vertical profile of dissolved radium (for dispersion).

Equation 12. Radium distribution coefficient calculated according to a modification of Equation 7.

Equation 13. For advective transport, the radium flux is roughly calculated as the average radium pore-water activity in the upper part of the core multiplied by the velocity.

Equation 14. In the case of dispersion, the maximum flux is a function of the dispersion coefficient and the decay constant.

Equation 15. OTIS model equation for stream.

Equation 16. OTIS model equation for storage zone.

Equation 17. Ground-water residence time is uniquely related to depth of water storage (multiplied by transect width) and divided by a water exchange flux.

Equation 18. Average recharge and discharge flux equation, estimated by dividing the exchange flux by the transect cross sectional width.