Contents Section Page Executive Summary......................................................................................................................ES-1 1 Introduction.........................................................................................................................1-1 1.1 Purpose of a Strategic 20-Year Master Plan........................................................1-2 1.2 Background .............................................................................................................1-2 1.3 Service Area and Customer Base .........................................................................1-2 1.4 Report Organization ............................................................................................1-10 2 Population and Water Demand Forecast Summary.....................................................2-1 2.1 Introduction.............................................................................................................2-1 2.2 Projected Population..............................................................................................2-1 2.2.1 Permanent Population ..............................................................................2-1 2.2.2 Seasonal Population..................................................................................2-2 2.2.3 Functional Population ..............................................................................2-2 2.3 Historic Water Production ....................................................................................2-5 2.3.1 Swimming Pool Construction Permits...................................................2-7 2.3.2 Current Homeowner Versus Former Homeowner Water Use...........2-8 2.4 Projected Finished Water Demand ......................................................................2-9 2.4.1 Peak Hour Demands...............................................................................2-10 2.5 Demand by Service Type.....................................................................................2-11 2.5.1 Demand by Service Type .......................................................................2-11 2.5.2 Unmetered Water....................................................................................2-14 2.6 Conclusions ...........................................................................................................2-14 3 Water Supply System ........................................................................................................3-1 3.1 Water Supply Wells................................................................................................3-1 3.2 Raw Water Quality.................................................................................................3-2 3.2.1 Biscayne Aquifer........................................................................................3-2 3.2.2 Floridan Aquifer ........................................................................................3-3 3.2.3 Additional Raw Water Facilities .............................................................3-4 3.3 Water Supply Permitting.......................................................................................3-4 3.3.1 Saline Water Intrusion ..............................................................................3-5 3.4 Wastewater Reuse..................................................................................................3-5 3.4.1 Feasibility of Implementing Wastewater Reuse ...................................3-5 3.5 Water Supply Recommendations.........................................................................3-6 3.5.1 Aquifer Storage and Recovery.................................................................3-6 GNV31013363605.DOC/061650022 II WB122005005DFB CONTENTS, CONTINUED Section Page 3.5.2 Low-Pressure Reverse Osmosis ..............................................................3-6 3.5.3 Desalination................................................................................................3-7 3.5.4 Wastewater Reuse.....................................................................................3-7 3.5.5 Water Supply Summary ...........................................................................3-8 3.5 Construction Cost Estimates for the Water Supply System..............................3-8 4 Water Treatment System...................................................................................................4-1 4.1 J. Robert Dean Water Treatment Plant ................................................................4-1 4.1.1 General Description ..................................................................................4-1 4.1.2 Treatment Facilities...................................................................................4-4 4.1.3 Summary ..................................................................................................4-13 4.2 Kermit H. Lewin Seawater Desalination Facility at Stock Island..................4-13 4.3 Marathon RO Emergency Facility, Marathon, Florida....................................4-15 4.4 Drinking Water Standards and Water Quality ................................................4-15 4.4.1 General......................................................................................................4-15 4.4.2 Recent Drinking Water Regulatory Changes ......................................4-15 4.4.3 Water Quality Data .................................................................................4-17 4.4.4 Conclusion................................................................................................4-19 4.5 Evaluation of Water Treatment Facilities..........................................................4-21 4.5.1 Water Demand and Treatment Capacity .............................................4-21 4.5.2 J. Robert Dean Water Treatment Plant .................................................4-25 4.5.3 Kermit H. Lewin RO Seawater Desalination Facility, Stock Island, Florida ..........................................................................................4-39 4.5.4 Marathon Island RO Seawater Desalination Facility, Marathon Island, Florida ..........................................................................................4-39 4.6 Water Treatment System Recommendations ...................................................4-39 4.6.1 J. Robert Dean Water Treatment Plant, Florida City, Florida ...........4-39 4.6.2 New LPRO Facility at the J. Robert Dean Water Treatment Plant, Florida City, Florida................................................................................4-40 4.6.3 Kermit H. Lewin RO Emergency Facility, Stock Island, Florida ......4-40 4.6.4 Marathon RO Desalination Facility, Marathon, Florida ....................4-41 4.6.5 Proposed Ocean Reef RO Facility, Ocean Reef, Florida.....................4-41 4.7 Construction Cost Estimates for the Water Treatment System .....................4-41 4.7.1 New LPRO Facility at the J. Robert Dean Water Treatment Plant, Florida City, Florida..................................................................................4-1 4.7.2 Kermit H. Lewin RO Desalination Facility, Stock Island, Florida....4-43 4.7.3 Marathon RO Desalination Facility, Marathon, Florida ....................4-43 4.7.4 Ocean Reef LPRO Treatment Plant, Ocean Reef, Florida ..................4-43 5 Water Transmission System.............................................................................................5-1 5.1 Existing Transmission System..............................................................................5-1 5.2 Evaluation of Existing Transmission System .....................................................5-2 5.2.1 Transmission System Mains ....................................................................5-2 5.2.2 Transmission System Booster Pump Stations and Storage Facilities ......................................................................................................5-5 GNV31013363605.DOC/061650022 III WB122005005DFB CONTENTS, CONTINUED Section Page 5.3 Transmission System Recommendations............................................................5-8 5.3.1 Transmission System Mains ....................................................................5-8 5.3.2 Transmission System Pump Stations and Storage Facilities .............5-10 5.4 Construction Cost Estimates for the Transmission System............................5-13 6 Water Distribution System...............................................................................................6-1 6.1 Existing Distribution Systems...............................................................................6-1 6.2 Evaluation of Distribution Systems .....................................................................6-2 6.2.1 Distribution Piping....................................................................................6-2 6.2.2 Distribution Pump Stations and Storage Facilities...............................6-3 6.3 Recommended Improvements and Upgrades to Distribution Systems.........6-9 6.3.1 Distribution Piping..................................................................................6-11 6.3.2 Existing Distribution Pump Stations and Storage Facilities..............6-11 6.3.3 Proposed Distribution Pump Stations and Storage Facilities ...........6-17 6.4 Construction Cost Estimates for the Distribution System..............................6-18 7 Capital Improvement Program ........................................................................................7-1