Basin-Specific Feasibility Studies, ECP Basins Evaluation of Alternatives Basin-Specific Feasibility Studies, ECP Basins Evaluation of Alternatives August 21, 2002 Presentation to STA Design Review Staff

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Study Area Seven ECP Basins ØS-5A, S-6, S-7, S-8, C-139 & C-139 Annex, and C-51 West ØGrouped into six STA-specific study areas (STA-1E, STA- 1W, STA-2, STA-3/4, STA-5, STA-6) ØAlso considered Acme Basin B for one alternative at STA-1E Preliminary Evaluations Completed for Each STA

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basic Guidance Evaluation Methodology ØEvaluation of Phosphorus and other Technical Parameters Walker’s DMSTA Model is primary tool used in evaluation of phosphorus parameters Supplemental Technology Standard of Comparison (STSOC) is used for other parameters ØEnvironmental Parameters - STSOC used ØEconomic Parameters Focus Today Is On Phosphorus Removal, Economics

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Objectives For Each STA, Identify At Least One Alternative That: ØIs Capable of Achieving Assumed Discharge Target of 10 ppb (Long-Term Geometric Mean) ØCan Be Completed On Or Before December 31, 2006 Other Alternatives Were Considered That May Not Meet One (Or Both) of Those Objectives

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Economics 50-Year Project Life ( )* Both Capital and Incremental O&M Costs Estimated ØAll costs estimated in 2002 Dollars Present Worth of Alternatives Computed As Of 12/31/02 ØCosts Escalated at 3%/yr from 2002 ØDiscount Rate of 6-3/8%/yr* * Consistent With Current Federal Planning Guidance

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Treatment Technologies For the ECP Basins, Primary Reliance on Submerged Aquatic Vegetation (SAV) To Achieve Objectives ØBased Analysis on Performance Similar to That in Cell 4 of the ENR Project (SAV_C4) As Recommended in STSOC ØConsidered Potential Impact on Treatment Performance If That Level of Performance Is Not Replicated (e.g., Sensitivity Analysis) Also Considered TP Reduction in Reservoirs Upstream of STAs, Where Presently Planned ØTP Reduction Performance Estimates Preliminary

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Sensitivity Analyses Sensitivity Analyses of Phosphorus Reduction Parameters ØVariation in BMP Performance Change in Inflow Concentration only ØVariation in SAV Performance Change in SAV vegetation community only ØAll Input Parameters (DMSTA Sensitivity Model) –Change in each parameter (over DMSTA runs) Uncertainty Analysis

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA 1W Tributary Area Consists of S-5A Basin Additional Inflows From Lake Okeechobee Include: ØBMP Makeup Water ØSTA Irrigation Water

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1W STA-1W Is Complete and In Operation Approx. 6,670 Acres in 3 Parallel Flow Paths Emergent Macrophyte Marsh In Cells 1, 2, 3 and 5A SAV In Cells 4 and 5B ØAnalyzed as SAV_C4 Legend: Existing SAV Existing Spillway Existing Pump Station Existing Control Structure Existing Seepage Pump Station

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1W Most Hydrologically Complex of the STAs Operation Significantly Influenced by Seepage Entering STA From WCA-1 ØHigher Estimated Inflows From Seepage Than At Any Other STA ØSeepage Further Increased Due to Presence of Seepage Collection Canal Between Cell 5A and WCA-1 Documented Less-Than-Ideal Flow Distribution in Cells 1-4

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1W Under High Rates of Flow, Side Discharges From Cell 3 (G-308) and Cell 4 (G-309) Difficulty in Controlling Flow Distribution Between Cells 1 and 2 ØG-255 Not An Operable Structure Two Outflow Pumping Stations (G-251 and G-310) Legend: Existing SAV Existing Spillway Existing Pump Station Existing Control Structure Existing Seepage Pump Station

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Model Approach Effective Areas of Cells 3 and 4 Limited to The Area Upstream of G-308 and G-309 ØCell 3 Area Reduced From 1,026 to 700 Acres ØCell 4 Area Reduced From 358 to 250 Acres Flow Distribution Between Cells Approximated Substantial Seepage Inflows Modeled As To Cells 1 and 3 Also Considered Cell-Cell Seepage, Cells 1 and 3 to Cells 2 and 4

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Baseline Conditions Average Annual Inflows; 160,334 ac-ft at Flow Weighted Mean TP Conc. Of 139 ppb ØInflows Consider 50% TP Removal in S- 5A Basin Runoff due to BMPs Average Annual Outflows; 188,100 ac- ft at Flow Weighted Mean TP Conc. Of 24 ppb, Geo. Mean of 24 ppb

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Model Verification Fully Operational, Permits Comparison of Actual To Modeled Performance Used Measured Data For Period Jan. 1, 2001 Through March 31, 2002 Measured Inflows at Structure G-302 (Almost All During 12-Month Period Ending March 31, 2002) Ø242,079 ac-ft, FW Mean TP Conc. Of 147 ppb Measured Outflows at G-251 and G-310, Combined Ø270,165 ac-ft, FW Mean TP Conc. Of 37 ppb

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Model Verification Applied “Existing Conditions” Model of STA-1W To Measured ØInflows at G-302 ØRainfall ØEvaporation Considered Both SAV_C4 and NEWS In Cells 4 and 5B

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Measured Vs. Predicted Outflow Volumes

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Measured Vs. Predicted Outflow TP Loads SAV NEWS

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Measured Vs. Predicted Daily Discharges

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Observations Model Closely Approximates Overall Discharge Volumes ØSuggests Seepage Inflows Modeled Appropriately Analysis Underscores Need for Replicating Cell 4 Performance ØUse of SAV-C4 Under Predicts Outflow Concentrations By Approx. 20% ØUse of NEWS Over Predicts Outflow Concentrations By Approx. 4%

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Observations While Closely Approximating Overall Discharge Volumes, Not a Good Match to Measured Daily Discharges ØDMSTA Predicts Outflows on All 455 Days; Actual Only 171 (Inflow at G-302 on 208 Days) ØPeak Inflow At G-302 = 2,476 cfs; Peak Modeled Outflow = 2,221 cfs; Peak Measured Outflow = 3,177 cfs ØMean Daily Inflow Rate at G-302 = 587 cfs; Modeled Mean Daily Outflow = 300 cfs; Measured Mean Daily Outflow = 796 cfs (All On Days With Measured Or Predicted Inflow > 0)

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Observations Limited Use of G-251 ØStation Operated On 54 Of the 455 Days ØMaximum Daily Discharge of 195 cfs (450 cfs Capacity) ØMean Daily Discharge (When Operating) Of 79 cfs ØOnly 6% Of Modeled Inflow and Seepage to Cells 1 and 3 Discharged at G-310 Mean Daily Discharge From G-310 (When Operating) Was 840 cfs Actual Flow Distribution To Cells Closely Approximated Model Assumptions

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Conclusions Model Adequately Represents Hydrologic/Hydraulic Performance Cell 5B Presently Performs More as NEWS Than SAV_C4; Suggests Need For Emphasis On Replicating SAV_C4 Performance Some Improvement In Current Performance Might Be Realized With Modified Operations ØCould Recover Presently Ineffective Areas in Cells 3 and 4 With Increased Use of G-251

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Alternative 1 Convert Cell 3 to SAV by 12/31/2006 Add Pumping Station for Maintenance of Stages in Cell 5 (Approx. 65 cfs) ØPump WCA-1 Seepage from Seepage Canal to Cell 5A Maintenance of Stages in Cells 1-4 through Normal Operation of G-250S ØSource of water: Seepage Canal Upstream, Direct Seepage to Cells 1,3 Legend: Conversion to SAV New Small Forward Pumping Station P

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Alternative 2 Physical Works As For Alt. 1, Plus.. Convert 745 Acres of Cell 1 to SAV ØNew Transverse Levee and Control Structures Required ØControl Structures Gated, Operable Structures Convert 470 Acres of Cell 2 to SAV ØNew Transverse Levee and Control Structures Required ØControl Structures Simple Culverts With Risers Modify Flow Distribution Between Cells ØReplace G-255 With Operable Structure Extend Power to New Cell 1 Structures, G-255 All complete by 12/31/2006 P Legend: Conversion to SAV New Control Structures New Small Forward New Levee Pumping Station

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1W Summary of Alternatives * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Sensitivity To SAV Performance * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Sensitivity To BMP Performance * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins General Sensitivity * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1E Tributary Area Consists of C-51 West Basin ØIncludes Rustic Ranches Subdivision Additional Inflows From ØS-5A Basin (Pumping Station S-5A Discharges Exceeding Hydraulic Capacity of STA-1W) ØLake Okeechobee (Minor Quantities for STA Irrigation)

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1E Present Design Approx. 5,132 Acres in Three Parallel Flow Paths (Cells 1-7) Preceded by 1,046 Acres of Distribution Cells ØConsidered As Add’l Treatment Area With Poor Flow Characteristics Emergent Macrophyte Marsh Current Design Basis Under Construction, Scheduled Completion Late 2003, Early 2004 Legend: Existing SAV Existing Spillway Existing Pump Station Existing Control Structure Existing Seepage Pump Station

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1E Differs From Other STAs Due To: ØHigh Volume of Seepage From WCA- 1 (Less Than STA- 1W, But More Than Other STAs) ØSubstantial Cell-to- Cell Seepage Flux - Used USACE Estimates ØDistribution Cells

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Baseline Conditions Average Annual Inflows; 133,331 ac-ft at Flow Weighted Mean TP Conc. Of 176 ppb ØInflows Consider 50% TP Removal in S- 5A Basin Runoff due to BMPs, 0% In C- 51 West Basin Average Annual Outflows; 148,400 ac- ft at Flow Weighted Mean TP Conc. Of 38 ppb, Geo. Mean of 34 ppb

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Alternative 1 Convert Cells 2, 4N, 4S and 6 to SAV by 12/31/06 Due to Available Gradient, Anticipate No Need For Forward Pumping Stations To Maintain Stages In SAV Cells Legend: Conversion to SAV

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins ACME Basin B Presently Discharges Directly to Refuge At Two Locations Average Annual Discharges Of 31,499 ac-ft At Flow Weighted Mean TP Conc. Of 71 ppb Ø25% Reduction In TP Loading Due To BMPs In Basin B Considered In Base Case Analysis

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Alternative 2 STA-1E Enhancements Identical To Those For Alternative 1 (SAV In Downstream Cells), 2006 Completion ØDischarges From Distribution Cells Redistributed; Cell 3 Increased, Cells 5/7 Reduced by 0.03 Of Total Acme Basin B Discharges Redirected To STA-1E, 2006 Completion ØInternal Improvements And Modifications in Acme Basins A and B to Deliver Discharges To C- 51 Canal Not Included In Estimated Costs ØWould Require New Or Additional Pumps To Lift Additional Inflows To Distribution Cells; Capacity Assigned At 491 cfs Legend: Conversion to SAV New Pumping Station Pump

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins STA-1E Summary of Alternatives * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Sensitivity To SAV Performance * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Sensitivity To BMP Performance * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration #Alternative 2 only

Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins Basin-Specific Feasibility Studies Everglades Construction Project Tributary Basins General Sensitivity * Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration