American Society of Farm Managers & Rural Appraisers Kevin Morrison, P.G. Project Coordinator – Desalination Engineering Brackish Groundwater Desalination Program Update October 2, 2014

Page 2 Outline Background Treatment Process Program Progress Program Cost

October 2, 2014 Page 3 Background

October 2, 2014 Page 4 SAWS Water Supply No Cutbacks

October 2, 2014 Page 5 What is Brackish Groundwater? Brackish groundwater contains total dissolved solids (TDS) greater than 1,000 milligrams per liter – Fresh: 0 – 1,000 mg/l – Edwards: 350 – 400 mg/l – Brackish: 1,000 – 10,000 mg/l – Saline: greater than 10,000 mg/l – Seawater: greater than 35,000 mg/l

October 2, 2014 Page 6 Why Brackish Desalination? Untapped resource Large volumes of available brackish water – Estimated over 2.7 billion acre-feet Resource close to San Antonio

October 2, 2014 Page 7 Feasibility

October 2, 2014 Page 8 Carrizo – Wilcox Cross Section

October 2, 2014 Page 9 Production Wells

October 2, 2014 Page 10 Membrane Pilot Testing Receive TCEQ capacity rating and permit Test membranes from three manufacturers Test pre-treatment/post treatment options – “Open System” vs. “Closed System” Additional Investigations – Concentrate Pipe Loop Study – Air Leak Testing – System fouling trend and membrane autopsy SAWS Membrane Pilot Test Unit Pilot Testing Goals

October 2, 2014 Page 11 Current BGD Program Phase I (2016) o 12 MGD or 13,440 Acre-feet/yr Phase II (2021) o 12 MGD or 13,440 Acre-feet/yr Phase III (2026) o 6 MGD or 6,720 Acre- feet/yr Total o 30 MGD or 33,600 Acre feet/yr

October 2, 2014 Page 12 Treatment Process

October 2, 2014 Page 13 Diagram by Osmonics, Inc. Reverse Osmosis Membrane Construction RO Treatment

October 2, 2014 Page 14 RO Treatment Acid CF AS Calcite Contactor, Degasification, Sodium hydroxide Product Well Concentrate Disposal Raw Water Blending RO Concentrate Pre-treatment Primary treatment Post treatment AS: Anti-scalent CF: Cartridge Filter MGD 2 MGD 10 MGD 1.11 MGD MGD 12 MGD

October 2, 2014 Page 15 What is Concentrate/Brine Reverse osmosis treatment plant produces two products – 90% permeate (30-60 mg/L TDS) – 10% concentrate (~15,000 mg/L TDS) Concentrate stream requires disposal

October 2, 2014 Page 16 Concentrate Disposal Options Considered

October 2, 2014 Page 17 Class I Test Injection Well Perforated Versus Open Hole Completion

October 2, 2014 Page 18 Injection Zone ~ 860 ft. Thick Confining Zone ~ 2,360 ft. Thick Production Zone ~ 600 ft. Thick Georgetown Edwards & Upper Glen Rose Limestone Midway Shale Anacacho Limestone Navarro Clay Wilcox Sand (Brackish Water) Upper Wilcox Clay Carrizo Sand (Fresh Water) Austin Chalk Eagle Ford Shale, Buda Limestone, & Del Rio Clay Well Construction Injection Tubing Retrievable Packer

October 2, 2014 Page 19 Class I Test Injection Well Total Project Cost: $4.83M Cost Per Linear Foot: $958 Project Costs

October 2, 2014 Page 20 Class I Test Injection Well Injection Well Results Depth: 5,000 – 5,300 ft Injection Zone  Edwards Limestone  Upper Glen Rose Limestone Native Edwards water salinity ~ 90,000 mg/L TDS 450 gpm Injection Rate Two Injection Wells required for BGD Phase I (about 1.1 MGD)

October 2, 2014 Page 21 Program Progress

October 2, 2014 Page 22 CMAR Process Process allows: – Contractor’s input in the design – Engineer’s involvement in construction planning – Qualification based selection – Guaranteed maximum price (GMP) – Pursue SAWS SMWB goals

October 2, 2014 Page 23 Program Components 12 - Production Wells 2 – Injection Wells Reverse Osmosis Treatment Plant Pipelines SCADA and Electrical system Security

October 2, 2014 Page 24 Activities Completed Design Completed – Wells – Conveyance – RO Treatment Plant – Electrical / SCADA – Security Construction and Guaranteed Maximum Price approved by SAWS Board in March Construction Manager at Risk in the procurement phase

October 2, 2014 Page 25 Current Activity Treatment Plant Earthwork – Jun. 21, 2014

October 2, 2014 Page 26 Current Activity Treatment Plant Earthwork – Sept. 9, 2014

October 2, 2014 Page 27 Program Cost

October 2, 2014 Page 28 Cost Total estimated construction cost: $ million $/AF: $1,177 / AF Construction in Progress Completion - October 2016 Phase I

October 2, 2014 Page 29 Questions?

American Society of Farm Managers & Rural Appraisers Kevin Morrison, P.G. Project Coordinator – Desalination Engineering Brackish Groundwater Desalination Program Update October 2, 2014