Storm Water Management May 6, 2009

WELCOME TO ST. LUCIE WE s T NO WAKE ZONE

District Services Potable water treatment and distribution Wastewater collection, treatment & reuse - Reclaimed irrigation distribution system 30% reuse / 70% surficial Landscape/Wetland/Preserve maintenance Surface water management - Drainage & storm water management

SLW Storm Water System Approx. 650 acres of RTPs (13.4%) 7 Major Drainage basins - 25 Individual basins acres 30 Control Structures 8 Exterior adjustable structures 9 Interior adjustable structures 13 fixed structures - 3 proposed adjustable

3 Off Site Outfalls C-108 Canal – 200 cfs peak discharge Turnpike Ditch – 400 cfs peak discharge - North of SLW Blvd C South of SLW Blvd Elkcam Monterrey Canal - Lake Charles - Vineyards

1995 “No Name Storm” Wetter than normal “wet season” Large inflows of water from I-95 into SLW Maintenance of conveyance systems - ditches & canals Lower basins were not completed or connected Need for implementation of adjustable structures

2004 Hurricane Frances 10” Rainfall Sept. 4 th 2004 Remnants of Hurricane Ivan 7” Rainfall Sept , 2004 Hurricane Jean 12” Rainfall Sept. 25, 2004 Street flooding 3-4 days

2005 Hurricane Wilma October 19 th ” Rainfall October 24 th ” Rainfall October 29 th ” Rainfall Street flooding 4-5 days

2008 T.S. Fay August 14th SLW Control Elevation T.S. Fay targeting Tampa & West Coast PSL on outer edge of cone of error Decision to lower gate 1’ below control August 16th Lake Levels Down District receives 4” rain event Lake Levels at or above control 1” of rain equals 4” rise in lake elevation August 19th T.S. Fay arrives with 14” of rain 3-12” diesel pumps are ordered and Centennial High, North I-95 Scripps, Turn Pike east of Home Depot

August 24th Residual water still in streets Community ingress/egress restored to H.O.A.s All gates open All pumps running All Lake levels above controlImpacts Property Damage Water intrusion through openings Water percolation through foundation slabs Water waves from passing vehicles Business Closures Publix, Sears, Burger King, Banks, Office buildings, Movie/Sports SLC School Bus Depot

Impacts Continued Impassable Streets SLW Boulevard Cashmere California Peacock Bethany Communities without Ingress/Egress CCE Kings Isle Cascades The Lakes Lake Forest Vineyards Belmont Lake Charles Etc………

Impacts Continued Impact on WWTP Lift Station Intrusion - Missing Cleanout Covers - Broken Cleanout Pipes Raw Sewage Spill

Project Drivers Residential Communities Impassable 3-5 days Residential & Commercial property damage throughout the community If Ike had hit after Fay - 1 st floor elevation in community would have been breached - Uncontrolled Outflows Downstream - Potential property damage $240,000,000

Solutions Larger Outflow Structures Capability to go to 2 feet Below Control Supplemental Pumping Earlier Implementation of Drain Down Technology - SCADA - Radio Telemetry - Water Level & Flow Sensors - Motorized Gates

Previous Recommendations Modify Interior Control Structures 6a Cascades (completed) 4c Catholic Church lake (in progress) Sun Terrace (in progress) 4C/2 Lake Whitney (in progress)

The Improvement Project Engineering & Design $108,000 Permitting $10,000 Management & Other $10,000 Construction $1,000,000 Contingency $21,300 TOTAL $1,149,300

Scope of Project Widen external gates # 2 and # 8 to allow maximum discharge per SFWMD permit Modify all external gates and 1 internal gate to 2 foot below control Remove existing dyke between Lake #1 and Lake # 2 to increase basin capacity and allow for faster discharge Motorize all external and one internal gate to eliminate manual operation Install PLC’s at each gate to operate remotely through the Districts SCADA system (System Control and Data Acquisition) Install water elevation monitors at all gates

Improvements Expected

Key Roles Elected and Public Officials Promotion and Support - HMGP** - I-95 60” pipe (Kolter) Permitting City of Port St Lucie SFWMD FDOT Design Arcadis Engineering SFWMD Integration Concepts

Estimated Schedule Design completed September 30 th 2009 Permitting Completed January 1 st 2010 Construction Phase #1 Fabrication of Gates February 1 st – April 30 th 2010 Installation completed by July 15 th 2010 Construction Phase 2 Power, meter cans, electric motors, water elevation monitors plc’s installed September 1 st 2010 Graphic configuration, Start up and Debugging completed for SCADA control completed September 15 th 2010

Thank You