basin-specific feasibility studies, ecp basins evaluation of alternatives basin-specific feasibility...

Basin-Specific Feasibility Studies,ECP Basins

Evaluation of Alternatives

Basin-Specific Feasibility Studies,ECP Basins

Evaluation of Alternatives

August 21, 2002August 21, 2002

Presentation to STA Design Review Staff

Basin-Specific Feasibility StudiesEverglades Construction Project Tributary Basins


Study AreaStudy Area

Seven ECP Basins S-5A, S-6, S-7, S-8, C-139 &

C-139 Annex, and C-51 West Grouped into six STA-specific

study areas (STA-1E, STA-1W, STA-2, STA-3/4, STA-5, STA-6)

Also considered Acme Basin B for one alternative at STA-1E

Preliminary Evaluations Completed for Each STA



Basic GuidanceBasic Guidance

Evaluation Methodology Evaluation 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

Environmental Parameters - STSOC used

Economic Parameters

Focus Today Is On Phosphorus Removal, Economics



ObjectivesObjectives

For Each STA, Identify At Least One Alternative That: Is Capable of Achieving Assumed Discharge

Target of 10 ppb (Long-Term Geometric Mean) Can Be Completed On Or Before December 31,

2006

Other Alternatives Were Considered That May Not Meet One (Or Both) of Those Objectives



EconomicsEconomics

50-Year Project Life (2007-2056)* Both Capital and Incremental O&M Costs

Estimated All costs estimated in 2002 Dollars

Present Worth of Alternatives Computed As Of 12/31/02 Costs Escalated at 3%/yr from 2002 Discount Rate of 6-3/8%/yr*

* Consistent With Current Federal Planning Guidance



Treatment TechnologiesTreatment Technologies

For the ECP Basins, Primary Reliance on Submerged Aquatic Vegetation (SAV) To Achieve Objectives Based Analysis on Performance Similar to That in Cell 4 of

the ENR Project (SAV_C4) As Recommended in STSOC Considered 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 TP Reduction Performance Estimates Preliminary



Sensitivity AnalysesSensitivity Analyses

Sensitivity Analyses of Phosphorus Reduction Parameters Variation in BMP Performance

• Change in Inflow Concentration only

Variation in SAV Performance• Change in SAV vegetation community only

All Input Parameters (DMSTA Sensitivity Model)– Change in each parameter (over 100-180 DMSTA runs)

• Uncertainty Analysis



STA 1WSTA 1W

Tributary Area Consists of S-5A Basin

Additional Inflows From Lake Okeechobee Include: BMP Makeup Water STA Irrigation Water



STA-1WSTA-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 Analyzed as

SAV_C4Legend:

Existing SAV Existing Spillway

Existing Pump Station Existing Control Structure

Existing Seepage

Pump Station

Cell 1

Cell 5A

Cell 3

Cell 2

Cell 5B

Cell 4

A.R.M. LoxahatcheeNational WildlifeRefuge (WCA 1)

EffectiveCell Area (ac) 1 1,490 2 941

3 1,0264 3585A 5625B 2,293

Total 6,670 acN

G-259

G-258

G-305 A-V

G-304 A-J

G-254 A-I

G-327 A

G-306 A-J

G-255

G-256

G-257 L-7Canal

DischargeCanal

Ocean Canal

G-252 H-J

S-5AS

G-300

G-303

G-302

G-308

G-309

S-5A

G-251

G-310

G-253 A-J

G-250 S

G-301



STA-1WSTA-1W

Most Hydrologically Complex of the STAs Operation Significantly Influenced by

Seepage Entering STA From WCA-1 Higher Estimated Inflows From Seepage Than At

Any Other STA Seepage 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



STA-1WSTA-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 G-255 Not An Operable

Structure

Two Outflow Pumping Stations (G-251 and G-310)

Legend:



Existing Seepage

Pump Station

Cell 1

Cell 5A

Cell 3

Cell 2

Cell 5B

Cell 4



3 1,0264 3585A 5625B 2,293

Total 6,670 acN

G-259

G-258

G-305 A-V

G-304 A-J

G-254 A-I

G-327 A

G-306 A-J

G-255

G-256

G-257 L-7Canal

DischargeCanal

Ocean Canal

G-252 H-J

S-5AS

G-300

G-303

G-302

G-308

G-309

S-5A

G-251

G-310

G-253 A-J

G-250 S

G-301



Model ApproachModel Approach

Effective Areas of Cells 3 and 4 Limited to The Area Upstream of G-308 and G-309 Cell 3 Area Reduced From 1,026 to 700 Acres Cell 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



Baseline ConditionsBaseline Conditions

Average Annual Inflows; 160,334 ac-ft at Flow Weighted Mean TP Conc. Of 139 ppb Inflows 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



Model VerificationModel 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) 242,079 ac-ft, FW Mean TP Conc. Of 147 ppb

Measured Outflows at G-251 and G-310, Combined 270,165 ac-ft, FW Mean TP Conc. Of 37 ppb



Model VerificationModel Verification

Applied “Existing Conditions” Model of STA-1W To Measured Inflows at G-302 Rainfall Evaporation

Considered Both SAV_C4 and NEWS In Cells 4 and 5B



Measured Vs. Predicted Measured Vs. Predicted Outflow VolumesOutflow Volumes

0

20000

40000

60000

80000

100000

120000

140000

160000

Measured Cumulative Outflow (cfs-day)

DMSTA Predicted Cumulative Outflow (cfs-day) - G302



Measured Vs. Predicted Measured Vs. Predicted Outflow TP LoadsOutflow TP Loads

0.00

2000.00

4000.00

6000.00

8000.00

10000.00

12000.00

14000.00

Measured Cumulative Load (kg)

DMSTA Predicted Cumulative Load (kg) - G302,SAV_C4

DMSTA Predicted Cumulative Load (kg) - G302, NEWS

SAV

NEWS



Measured Vs. Predicted Measured Vs. Predicted Daily DischargesDaily Discharges

0

500

1000

1500

2000

2500

3000

3500

Measured Outflows (cfs)

DMSTA Predicted Outflows (cfs) - G302

De



ObservationsObservations

Model Closely Approximates Overall Discharge Volumes Suggests Seepage Inflows Modeled

Appropriately

Analysis Underscores Need for Replicating Cell 4 Performance Use of SAV-C4 Under Predicts Outflow

Concentrations By Approx. 20% Use of NEWS Over Predicts Outflow

Concentrations By Approx. 4%




While Closely Approximating Overall Discharge Volumes, Not a Good Match to Measured Daily Discharges DMSTA Predicts Outflows on All 455 Days; Actual Only

171 (Inflow at G-302 on 208 Days) Peak Inflow At G-302 = 2,476 cfs; Peak Modeled Outflow

= 2,221 cfs; Peak Measured Outflow = 3,177 cfs Mean 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)




Limited Use of G-251 Station Operated On 54 Of the 455 Days Maximum Daily Discharge of 195 cfs (450 cfs Capacity) Mean Daily Discharge (When Operating) Of 79 cfs Only 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



ConclusionsConclusions

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 Could Recover Presently Ineffective Areas in

Cells 3 and 4 With Increased Use of G-251



Alternative 1Alternative 1

Convert Cell 3 to SAV by 12/31/2006

Add Pumping Station for Maintenance of Stages in Cell 5 (Approx. 65 cfs) Pump WCA-1 Seepage

from Seepage Canal to Cell 5A

Maintenance of Stages in Cells 1-4 through Normal Operation of G-250S Source of water:

Seepage Canal Upstream, Direct Seepage to Cells 1,3

Legend:

Conversion to SAV

New Small Forward

Pumping StationP

Cell 1

Cell 5A

Cell 3

Cell 2

Cell 5B

Cell 4



3 1,0264 3585A 5625B 2,293

Total 6,670 acN

G-259

G-258

G-305 A-V

G-304 A-J

G-254 A-I

G-327 A

G-306 A-J

G-255

G-256

G-257 L-7Canal

DischargeCanal

Ocean Canal

G-252 H-J

S-5AS

G-300

G-303

G-302

G-308

G-309

S-5A

G-251

G-310

G-253 A-J

G-250 S

G-301

P



Alternative 2Alternative 2 Physical Works As For Alt. 1, Plus.. Convert 745 Acres of Cell 1 to SAV

New Transverse Levee and Control Structures Required

Control Structures Gated, Operable Structures

Convert 470 Acres of Cell 2 to SAV New Transverse Levee and

Control Structures Required Control Structures Simple Culverts

With Risers

Modify Flow Distribution Between Cells Replace G-255 With Operable

Structure

Extend Power to New Cell 1 Structures, G-255

All complete by 12/31/2006P

Legend:

Conversion to SAV New Control Structures

New Small Forward New Levee

Pumping Station

Cell 1

Cell 5A

Cell 3

Cell 2

Cell 5B

Cell 4


EffectiveCell Area (ac) 1 745 2 471

3 1,4454 7205A 5625B 2,293

Total 6,670 acN

G-259

G-258

G-305 A-V

G-304 A-J

G-254 A-I

G-327 A

G-306 A-J

G-256

G-257 L-7Canal

DischargeCanal

Ocean Canal

G-252 H-J

S-5AS

G-300

G-303

G-302

G-308

G-309

S-5A

G-251

G-310

G-250 S

G-253 A-J

P

G-255

G-301



STA-1W STA-1W Summary of AlternativesSummary of Alternatives

* Computed Value Less than Calibration Range, Reported at Lowest Sustainable Concentration

Performance Measure: Unit Baseline Alt 1 Alt 2Anticipated Start Date Date N/A Jan 2004 Jan 2003Date of Completion Date N/A Dec 2006 Dec 2006Long-term Flow-weighted Mean ppb 24-30 19 - 27 14* - 22Long-term Geometric Mean ppb 24-26 14 - 16 10* - 13Phosphorus Load Reduction kg N/A 65,060 125,230Phosphorus Load Reduction % N/A 23.0 44.3Capital Cost (2002 Dollars) $ N/A $1,320,000 $6,100,000Inc. O&M Cost (2002 Dollars) $/Yr N/A $50,000 $165,00050-yr Present Worth Cost (12/31/02) $ N/A $2,232,000 $9,049,000Cost Effectiveness $/kg N/A $34 $72



Sensitivity To SAV Sensitivity To SAV PerformancePerformance

TP Conc. For Different SAV Communities

F.W. Geo. F.W. Geo.STA-1W Inflows 139 -- 139 --STA-1W Outflows 24 24 30 26STA-1W Inflows 139 -- 139 --STA-1W Outflows 19 14 27 16STA-1W Inflows 139 -- 139 --STA-1W Outflows 14* 10* 22 13

Location SAV_C4 NEWS

Alternative 2

Baseline

Alternative 1

Condition




Sensitivity To BMP Sensitivity To BMP PerformancePerformance


F.W. Geo. F.W. Geo. F.W. Geo.STA-1W Inflows 199 -- 139 -- 78 --STA-1W Outflows 30 31 24 24 18 17STA-1W Inflows 199 -- 139 -- 78 --STA-1W Outflows 23 17 19 14 14 10STA-1W Inflows 199 -- 139 -- 78 --STA-1W Outflows 15 11 14* 10* 14* 10*

Condition LocationTP Conc. For BMP Load Reduction in S-5A Basin of

25% 50% 75%

Baseline, Existing

Alternative1

Alternative 2



General SensitivityGeneral Sensitivity


TP Conc. For BMP Load Reduction in STA-1W10th Percentile Est. 50th Percentile Est. 90th Percentile Est.

F.W. Geo. Load F.W. Geo. Load F.W. Geo. LoadBaseline, Existing STA-1W Outflows 19 18 4,311 24 24 5,654 30 30 6,996

Alternative 1 STA-1W Outflows 14 10 3,293 19 14 4,352 23 17 5,412

Alternative 2 STA-1W Outflows 14* 10* 3,149* 14* 10* 3,149* 17 12 3,751

Condition Location



STA-1E STA-1E

Tributary Area Consists of C-51 West Basin Includes Rustic Ranches

Subdivision

Additional Inflows From S-5A Basin (Pumping

Station S-5A Discharges Exceeding Hydraulic Capacity of STA-1W)

Lake Okeechobee (Minor Quantities for STA Irrigation)



STA-1ESTA-1E

Present Design Approx. 5,132 Acres in Three Parallel Flow Paths (Cells 1-7)

Preceded by 1,046 Acres of Distribution Cells Considered 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 Seepage

Pump Station

Cell 3

East Distribution Cell


Cell 6 Cell 4N

Cell 4S

Cell 2

Cell 1Cell 5

West Distribution Cell

S-369

C-51 Canal

S-372

S-370

S-364

S-363S-366S-373

S-368

S-374 S-371 G-367

N

S-365

S-375

Cell 7

S-361

S-319

S-362

G-311

EffectiveArea (ac)Cell

1 5562 5523 5894N 6454S 752 5 5716 1,0497 418

Total 5,132 acDischarge Canal



STA-1ESTA-1E

Differs From Other STAs Due To: High Volume of

Seepage From WCA-1 (Less Than STA-1W, But More Than Other STAs)

Substantial Cell-to-Cell Seepage Flux - Used USACE Estimates

Distribution Cells



Baseline ConditionsBaseline Conditions

Average Annual Inflows; 133,331 ac-ft at Flow Weighted Mean TP Conc. Of 176 ppb Inflows 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




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

Cell 3



Cell 6 Cell 4N

Cell 4S

Cell 2

Cell 1Cell 5


S-369

C-51 Canal

S-372

S-370

S-364

S-363S-366S-373

S-368

S-374 S-371 G-367

N

S-365

S-375

Cell 7

S-361

S-319

G-311


1 5562 5523 5894N 6454S 752 5 5716 1,0497 418


S-362



ACME Basin BACME 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 25% Reduction In TP Loading

Due To BMPs In Basin B Considered In Base Case Analysis




STA-1E Enhancements Identical To Those For Alternative 1 (SAV In Downstream Cells), 2006 Completion Discharges 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 Internal Improvements And

Modifications in Acme Basins A and B to Deliver Discharges To C-51 Canal Not Included In Estimated Costs

Would Require New Or Additional Pumps To Lift Additional Inflows To Distribution Cells; Capacity Assigned At 491 cfs

Legend:

Conversion to SAV

New Pumping StationPump

Cell 3



Cell 6 Cell 4N

Cell 4S

Cell 2

Cell 1Cell 5


S-369

C-51 Canal

S-372

S-370

S-364

S-363S-366S-373

S-368

S-374 S-371 G-367

N

S-365

S-375

Cell 7

S-361

S-319

G-311


1 5562 5523 5894N 6454S 752 5 5716 1,0497 418


PUMP

S-362



STA-1E STA-1E Summary of AlternativesSummary of Alternatives


Performance Measure: Unit Baseline Alt 1 Alt 2Anticipated Start Date Date N/A Jan 2005 Jan 2003Date of Completion Date N/A Dec 2006 Dec 2006Long-term Flow-weighted Mean ppb 38 15 - 24 15 - 24Long-term Geometric Mean ppb 34 10* - 11 10* - 11Phosphorus Load Reduction kg N/A 220,475 323,010Phosphorus Load Reduction % N/A 62.8 66.1Capital Cost (2002 Dollars) $ N/A $940,000 $8,520,000Inc. O&M Cost (2002 Dollars) $/Yr N/A $40,000 $285,00050-yr Present Worth Cost (12/31/02) $ N/A $1,678,000 $13,764,000Cost Effectiveness $/kg N/A $8 $43



Sensitivity To SAV Sensitivity To SAV PerformancePerformance


TP Conc. For Different SAV Communities

F.W. Geo. F.W. Geo.STA-1E Inflows 176 -- 176 --STA-1E Outflows 15 10* 24 11STA-1E Inflows 156 -- 156 --STA-1E Outflows 15 10* 24 11

SAV_C4 NEWS

Alternative 1

Alternative 2 (with ACME)

Condition Location



Sensitivity To BMP Sensitivity To BMP PerformancePerformance


#Alternative 2 only

F.W. Geo. F.W. Geo. F.W. Geo.STA-1E Inflows 187 -- 176 -- 127 --STA-1E Outflows 38 35 38 34 31 27STA-1E Inflows 187 -- 176 -- 127 --STA-1E Outflows 14* 10* 15 10* 14* 10*STA-1E Inflows 170 -- 156 -- 111 --STA-1E Outflows 15 10* 15 10* 14* 10*

Baseline, Existing

Alternative 1Alternative 2 (with ACME)

Condition Mid HighLocationTP Conc. For BMP Load Reduction

Low

Source Low Mid HighC-51 Basin 0% 0% 25%L-101/EAA WPB Basin 25% 50% 75%L.O. Water Supply 0% 0% 0%Rustic Ranch 0% 0% 25%ACME Basin B# 0% 25% 50%



General SensitivityGeneral Sensitivity


TP Conc. For BMP Load Reduction in STA-1E10th Percentile Est. 50th Percentile Est. 90th Percentile Est.

F.W. Geo. Load F.W. Geo. Load F.W. Geo. LoadBaseline, Existing STA-1E Outflows 29 25 5,349 38 34 7,026 47 42 8,703

Alternative 1 STA-1E Outflows 14* 10* 2,479* 15 10* 2,616 18 10* 3,231Alternative 2 (with ACME) STA-1E Outflows 14* 10* 3,034* 15 10* 3,310 19 10 4,085

Condition Location

basin-specific feasibility studies, ecp basins evaluation of alternatives basin-specific feasibility...

Documents

sta slide

ecp basins s

staspecific study areas

enr project sav

acme basin b

year project life

economics slide

economic parameters