Downloaded 25 times
Uploaded byThe Texas Network, LLC
SAWS - Development of Brackish Groundwater Desalination Project
The presentation discussed the San Antonio Water System's (SAWS) Twin Oaks Brackish Groundwater Desalination Program. The program will develop brackish groundwater from the Carrizo-Wilcox and Gulf Coast aquifers using reverse osmosis treatment and deep well injection of concentrate. Phase I will provide 12 million gallons per day by 2016 at an estimated cost of $192.66 million. The program aims to ultimately supply 30 million gallons per day through phased expansions to help meet the region's increasing water demands through 2060 in a cost-effective and sustainable manner.
More Related Content
Similar to SAWS - Development of Brackish Groundwater Desalination Project
More from The Texas Network, LLC
SAWS - Development of Brackish Groundwater Desalination Project
- 1. TWCA 2014 Mid-YearConference W. John Seifert, Jr., P.E. LBG-Guyton Associates Kevin Morrison, P.G. San Antonio Water System Development of Brackish Groundwater Desalination Project: SAWS Twin Oaks Brackish Groundwater Desalination Program June 12, 2014
- 2. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 2 Topics • Groundwater Hydrology • Groundwater Supply Development • Program Update
- 3. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 3 What is Brackish Groundwater? • Practical Definition: Brackish groundwater contains from 1,000 to 10,000 mg/L TDS Fresh Brackish Saline Fresh Slightly-saline Moderately-saline Very-saline 1,000 mg/L 3,000 mg/L 10,000 mg/L
- 4. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 4 Why Consider Brackish Groundwater? • By 2060 – Population will increase by 82% to 46.3 million – Demand will increase by 22% – Municipal demand will increase 71% – Supply (existing sources) decrease 10% – Advances in treatment technology – Data from TWDB 2012 State Water Plan
- 5. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 5 Carrizo-Wilcox Gulf Coast Hueco-Mesilla Bolsons Major Aquifers
- 6. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 6 Carrizo-Wilcox Aquifer
- 7. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 7 Gulf Coast Aquifer (Wells >500 ft deep)
- 8. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 8 Aquifers with Substantial Amounts of Brackish Groundwater • Carrizo-Wilcox Interbedded sand, silt and clay • Gulf Coast Interbedded sand, silt and clay • Hueco-Messilla Bolsons Silt, sand and gravel
- 9. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 9 Favorable Conditions for a Brackish Groundwater Project • Water quantity adequate • Water quality acceptable – Total dissolved solids content slightly saline to moderately saline • Resource located in reasonable proximity to demand • Regulatory environment reasonable • RO Concentrate Management can be cost contained • Project effects are acceptable
- 10. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 10 Carrizo-Wilcox Aquifer - Strive for locations with greater areal extent of resource
- 11. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 11 Geologic Description of an Area •Electric Log Data Point
- 12. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 12 Carrizo-Wilcox and Gulf Coast Aquifers Brackish Groundwater Resource Below Fresh Groundwater Land Surface Increasing Depth Brackish Water Sand (Yellow) Freshwater Sand (Blue) Clay (Brown)
- 13. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 13 Wilcox Brackish Sands in Gonzales County F. Passmore #1
- 14. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 14 Groundwater Supply Development
- 15. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 15 Sequence of Supply Development • Evaluate desk top data • Outline area for test drilling if needed • Perform drilling and water quality testing • Design wells and wellfield with appropriate well spacing • Construct and test wells and evaluate water quality data • Equip wells and construct water conveyance infrastructure
- 16. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 16 Screen Installation And Gravel Packing
- 17. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 17 Large Capacity Brackish Water Production Well
- 18. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 18 Production Well Testing Obtain data on aquifer productivity, can be used for groundwater flow modeling Obtain water quality data Collect data regarding well efficiency
- 19. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 19 Program Update
- 20. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 20 Program General Information • Source Water – Lower Wilcox Formation – 12 Production Wells – Avg. depth 1,600 ft. • Treatment Process – Reverse Osmosis – 90% Recovery • Concentrate Disposal – Deep Well Injection – 5,000 ft. depth – Two injection wells required for Phase I
- 21. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 21 Program Components • Production Wells • Conveyance System (Pipelines) • Reverse Osmosis Treatment Plant • Injection Wells • Electrical / SCADA
- 22. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 22 SAWS BGD Program • Phase I (2016) – 12 MGD or 13,440 Acre-feet/yr. • Phase II (2021) – 12 MGD or 13,440 Acre-feet/yr. • Phase III (2026) – 6 MGD or 6,720 Acre-feet/yr. • Total – 30 MGD or 33,600 Acre-feet/yr.
- 23. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 23 Lessons Learned from Past Projects • Program Manager not having control over designers • Low bid contractor may not be best qualified • No contractor’s input in the design document preparation • Claims, litigation and delays • Change orders • Lack of cooperation
- 24. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 24 • Designer Engineers are under the contract of the Program Manager • Sub-contractors are selected based on qualifications and experience under the Construction Manager At Risk (CMAR) procurement • CMAR contractor were involved in the design phase • Performance Incentive proposed Procurement Plan
- 25. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 25 Program Structure - 4 Design Teams - 20 Design Sub-Consultants - 17 SMWB Firms - 21 Local Firms SAWS Construction Manager at Risk (CMAR) Zachry Parsons Water Resources JV Program Manager Black & Veatch Corp. Sub-ContractorsDesign Sub-Consultants - 12 Construction Packages - Multiple Subcontractors
- 26. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 26 20132012 Conceptual Design Pre- Construction Design 2015 20162014 Program Completion October 2016 Construction Management Services Construction Commi- ssion Commi- ssion Warranty Warranty 2017 2018 Program Manager (PM) Construction Manager at Risk (CMAR) GMP Board Award March 2014 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
- 27. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 27 Guaranteed Maximum Price • CMAR will publicly bid each construction package and recommend most qualified best value sub-contractor • The payment to CMAR will be based on actual cost of construction not to exceed the GMP • Should the actual cost be lower than the GMP, the difference will be a credit to SAWS
- 28. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 28 Shared Performance Incentives • Maximum of $250,000 to Program Manager • Maximum of $750,000 to CMAR • Objective Parameters: • Budget • Completion Schedule • Change Control • Subjective Parameters: • Partnering, Quality of service, Conflict Resolution, Timely Responses
- 29. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 29 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 13.11MGD 2MGD 10 MGD 1.11MGD 11.11MGD 12 MGD
- 30. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 30 Production vs. Disposal Land Surface Georgetown Edwards & Upper Glen Rose Limestone TD = 5,040 ft. Midway Shale Anacacho Limestone Navarro Clay Not to Scale TD = 1,600 ft. Production Well Injection Well Confining Zone ~2,360 ft. Thick Wilcox Sand (Brackish Water) Upper Wilcox Clay Eagle Ford Shale, Buda Limestone, & Del Rio Clay Austin Chalk Carrizo Sand (Fresh Water) Injection Zone ~ 860 ft. Thick Production Zone ~ 600 ft. Thick
- 31. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 31 Remaining Work for Phase I • Additional four production wells • Additional injection well • Reverse Osmosis treatment plant • Pipelines • SCADA and Electrical system
- 32. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 32 Construction Package Procurement Work Package Description SAWS Approval of CMAR Recommendation 1 Enabling (Silt Fencing / Site Fencing) May-14 2 Site Work May-14 3 Foundation May-14 4 Electrical / SCADA May-14 5 Water Treatment Plant Jun-14 6 Pipelines Jun-14 7 Access Roads Jun-14 8 Well Fit Out Jul-14 9 Production Wells Jul-14 10 Injection Wells Jul-14 11 Landscaping Dec-14 12 Security
- 33. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 33 Cost • Phase I total estimated construction cost is $192.66 million • $/AF: $1,177 / AF Phase I
- 34. June 12, 2014 SAWSBrackish Groundwater Desalination Program Page 34 Questions?
- 35. TWCA 2014 Mid-YearConference W. John Seifert, Jr., P.E. LBG-Guyton Associates Kevin Morrison, P.G. San Antonio Water System Development of Brackish Groundwater Desalination Project: SAWS Twin Oaks Brackish Groundwater Desalination Program June 12, 2014
Editor's Notes
- #23 Approximately 53,760 Households