1. ASCE – Tri‐County Workshop
L‐8 Flow Equalization Basin
and C‐51 Reservoir
May 10, 2013
Tommy Strowd, PE
SFWMD Assistant Executive Director

2. Restoration Strategies Key Projects
2

3.  Existing
 Northwestern Palm Beach
County
 Former 950‐acre rock mine
 46,000 ac/ft of storage
 Capture and store excess surface
water from L‐8 basin
 Benefit South Florida’s ecosystem
and sustain regional water
supplies
L‐ 8 Reservoir
L‐ 8 Canal
J WCorbett Wildlife
Management Area
Water
Catchment
Area
Loxahatchee
Slough
Arthur R. Marshall
Loxahatchee
National Wildlife
Refuge
WellingtonWellington
Fox TrailFox Trail Royal Palm
Beach
Royal Palm
Beach
Palm Beach
International
Airport
Palm Beach
International
Airport
Lake WorthLake Worth
GreenacresGreenacres
Rivera
Beach
Rivera
Beach
North Palm
Beach
North Palm
Beach
West Palm
Beach
West Palm
Beach
Palm Beach
Gardens
Palm Beach
Gardens
Southern BlvdSouthern Blvd
TurnpikeTurnpike
95
95
95
TurnpikeTurnpike
 Existing
 Northwestern Palm
Beach County
 Former 950‐acre rock
mine
 46,000 ac/ft of storage
 Benefit South Florida’s
ecosystem
 Essential Feature in the
District’s Restoration
Strategies for WQ in
the Everglades
 Assist in sustaining
regional water supplies
L‐8 ReservoirL‐8 Reservoir
L‐8 Reservoir

4. Arthur R. Marshall
Loxahatchee
National Wildlife
Refuge
 Existing
 Northwestern Palm Beach
County
 Former 950‐acre rock mine
 46,000 ac/ft of storage
 Capture and store excess surface
water from L‐8 basin
 Benefit South Florida’s ecosystem
and sustain regional water
supplies
L‐ 8 Reservoir
L‐ 8 Canal
J WCorbett Wildlife
Management Area
Water
Catchment
Area
Loxahatchee
Slough
Arthur R. Marshall
Loxahatchee
National Wildlife
Refuge
WellingtonWellington
Fox TrailFox Trail Royal Palm
Beach
Royal Palm
Beach
Palm Beach
International
Airport
Palm Beach
International
Airport
Lake WorthLake Worth
GreenacresGreenacres
Rivera
Beach
Rivera
Beach
North Palm
Beach
North Palm
Beach
West Palm
Beach
West Palm
Beach
Palm Beach
Gardens
Palm Beach
Gardens
Southern BlvdSouthern Blvd
TurnpikeTurnpike
95
95
95
TurnpikeTurnpike
Existing L-8
Reservoir
Existing L-8
Reservoir
Proposed C‐51
Reservoir
Proposed C‐51
Reservoir
 Proposed
 Located in western
Palm Beach County
 75,000 ac/ft of
storage
 Capture and store
excess surface water
from C‐51 basin
 Increased water
storage and delivery
to help benefit South
Florida’s regional
water supplies
 Reduce harmful
discharges to the
Lake Worth LagoonLake Worth
Lagoon
Lake Worth
Lagoon
C‐51 Reservoir

5. L‐8/Northern
ITID Basin
Lake
Okeechobee
C‐51 West
Basin
Source of Water

6. L‐8 Flow
Equalization
Basin (FEB)
6

7. L‐8 Flow Equalization Basin (FEB)
• Component of the Eastern Flow Path
– Storage initially acquired in 2003
• 950 acres, Excavated to ‐42 feet NAVD,
45,000 acre feet capacity
– Divided into 6 cells
– Adjacent to and west of the L‐8 Canal
7

8. L‐8 Flow Equalization Basin (FEB)
• Component Purpose
– Part of Eastern Flow Path
• Attenuates peak flows from S‐5A and C‐51W
basins
• Reduces impact of storm event inflows and
optimizes STA inflow rates
• Works in conjunction with other Eastern Flow
Path Projects
– L‐8 Divide Structure, STA 1W Expansion, S‐375
Structure, S‐5A South Divide Structure
8

9. L‐8 Flow Equalization Basin (FEB)
Unique Geology
9

11. L‐8 Flow Equalization Basin (FEB)
Project Description
• Design and Construct Infrastructure to
Utilize Existing Storage
– 450 cfs outflow pump station
– 3,000 cfs inflow structure
– Embankment revetment – Soil Cement
– Reservoir Improvements – Cell‐to‐cell cuts
11

12. • Executed Design/Build Contract in
September 2012
– Archer Western/Jacobs Engineering
– $64 M
– Construction complete
• 18‐April‐2015
– Testing and Commissioning Complete
• 15‐Oct‐2015
12
L‐8 Flow Equalization Basin (FEB)
Project Overview

13. L‐8 Flow Equalization Basin (FEB)
Project Overview
13

14. L‐8 FEB
Pump Station
L‐8 FEB
Pump Station

15. L‐8 Flow Equalization Basin (FEB)
Soil Cement Revetment
TOB 23’ NAVD
Ties into
existing
rock shelf
~ 3‐5’ NAVD
15

16. L‐8 Flow Equalization Basin (FEB)
Dewatering Operations
16

17. C‐51 Reservoir
Proposed Project
17

18. C‐51 Reservoir
Future Water Supplies
• Lower East Coast Water
Supply Plan under way
– Targeted for
completion 2013
• Water sources capped
– Regional Water
Availability Rule
approved 2007
• Feasibility Study focus
– Modeling of storage
capability
– Quantity of water lost
to tide
– Ability to move water
through canal system
to create head

19. C‐51 Reservoir
Sub‐Regional Geology

20. C‐51 Reservoir
C‐51 Discharges to Lake Worth Lagoon

21. C‐51 Reservoir
Saltwater Intrusion

22. C‐51 Reservoir
C‐51 Canal Conveyance Capacity
• Challenges for western PBC
communities

23. C‐51 Reservoir
Conveyance
Reports have shown that it
is feasible to use a
combination of District &
Lake Worth Drainage
District facilities

24. C‐51 Reservoir
Summary of Benefits
• Regionally significant project with
multiple public purposes
• Beneficial use of water lost to tide
• Decrease in harmful fresh water
releases to Lake Worth Lagoon
• Long‐term & cost‐effective Alternative
Water Supply
• Potential flood relief for western Palm
Beach County
• Sea level rise & saltwater intrusion
benefits
• Location and geology
• Cross roads
• Extensive canal infrastructure &
conveyance capabilities
• Stakeholder interest and support

25. C‐51 Reservoir
SFWMD Considerations
 Construction: cost, schedule,
performance, technology,
completion and delivery
 Operations and Maintenance: cost
and performance (fee)
 Renewal, replacement and life cycle
costs
 Supply of water
 Contracts for water storage/market
alternatives
 Financing/Credit Rating
 Regulatory

26. C‐51 Reservoir
District Infrastructure Connections Could
Substantially Reduce Project Costs for Utilities
Phase 1 costs with independent
Infrastructure $186.5 million
Phase 1 costs with connection
to L‐8 Reservoir $150.5 million

27. Questions