1. Report on Evaluation of
Proposed Camp Pendleton
Seawater Desalination Project
Water Planning Committee
APRIL 25, 2013
Cesar Lopez
Senior Water Resources Specialist

2. Presentation Outline
Background
Report on latest planning and technical
studies
 Off-Shore Technical Studies
 Site Development Evaluations
 Product Water Conveyance Analyses
Preliminary Cost Estimates
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3. Proposed Desalination Project
• 50 - 150 mgd seawater RO Project
• Phased implementation
• Unique, large coastal site at top of
Aqueduct system
• 2 potential sites approved by the
Base for further study
• Unlike Carlsbad, project would
require new seawater intake and
discharge facilities
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4. Potential Project Benefits to Camp Pendleton
• RELIABILITY
– Drought-proof water supply located on the base
• WATER QUALITY
– High quality product water
– Potential blending opportunity
• OCEAN OUTFALL
– Potential for dual-use outfall for treated wastewater and concentrate
from desalination plant
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5. Project Background
• Conceptual feasibility study completed
• Board added additional technical and environmental studies to CIP
in 2009
• Planning MOU between SDCWA and MCBCP executed in 2010
established framework for cooperation during performance of
studies
• Consultant contracts executed in 2011 for:
• Technical Studies – Issues and impacts of offshore facilities
• Site Development Evaluations – Plant and onshore infrastructure
• Product Water Conveyance System Analyses
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6. Technical Studies Objectives
Intakes:
• Determine viability of subsurface intake
• Permitting agencies will require evaluation of alternative intake
methods
• Considered to have least impact to marine life
• Locate and configure open ocean intake
• Can be designed to minimize marine impacts
Brine Discharge:
• Locate and configure discharge system
• Minimize marine impacts
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7. Technical Studies - Geologic / Hydrogeologic
Investigations
• Conducted Geophysical Survey using seismic reflection
• Drilled exploratory boreholes
• Constructed test well and pump tested offshore aquifer
• Built Groundwater
Model
Key Findings:
• Large sub-seafloor ancient river channel
• Potential favorable geology to support
large subsurface intake system
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8. Technical Studies - Marine Environment
Investigations
• Physical Oceanography
– Ocean currents
– Wave pressure
• Water Quality Monitoring and Sampling
– Temperature
– Salinity
– Boron / Bromide
– Etc.
• Marine Biology Monitoring and Sampling
– Ichthyoplankton (larvae)
– Phytoplankton (algae)
– Demersal Species (fish)
– Infauna Invertebrate (sea-floor habitants)
Key Findings:
• Typical marine environment –
nothing unusual
• No fatal flaws to siting open
ocean intake and discharge
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9. • Ancient river channel provides favorable
geology for developing a sub-surface intake
• Open ocean intakes are feasible with low and
manageable marine environment impacts
• Potential lower cost
• Oceanographic conditions (i.e. ocean currents,
wave action) and marine habitat in project area
are favorable for siting a brine discharge
diffuser system at approx. 40 ft. depth
• Geotechnical conditions are suitable for soft-
ground tunnel construction
Technical Studies – Key Conclusions
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12. Site Development Evaluations Objectives
• Analyze site access, traffic flow, space availability and security
• Determine optimal and reliable treatment processes for project
• For maximum utilization, consider producing “untreated” water
• Determine power requirements, supply source and transmission
• Screened
Open Ocean
• Subsurface
Prepare water for
desalination process
• Conventional or
membrane process
• Desalination
Process
• Re-hardening
• Disinfection
Residual
• Treated Water System
• Untreated Water System
Pre-
treatment
Intake
System
Reverse
Osmosis
Post
Treatment
Key Treatment Process Design Elements
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13. MCTSSA Site Rendering
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14. SRTTP Site Rendering
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15. • Both sites are viable for construction and operation
• SRTTP Site offers the best site access
• “Untreated” water production possible
• Maximum plant utilization
• Eliminates any potential overlap with treatment plant production
• Increased cost of “re-treatment”
• Cost savings likely due to reduced chemical requirements and potential
elimination of second pass RO
• Phase 1 (50 mgd) project can be supported by existing power supply
infrastructure.
• Future phases would require new power supply infrastructure ($91 - $164 million)
Site Evaluations – Key Conclusions
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16. Product Water Conveyance Analyses
• 19 – 21 miles 72 inch diameter pipeline
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17. Product Water Conveyance
Key Conclusions
• The southern alignment provides the best opportunity for efficient
integration into the Water Authority Aqueduct system
• Shorter alignment
• Best alignment for both untreated and treated water integration
• least direct impact to MCBCP
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100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
Elevation(ft)
Length (ft)
Pipeline Reach
HGL of Pipeline 4
EL 1242
150 MGD – EL 1300
100 MGD – EL 1272
50 MGD – EL 1254
2A 2B 2C 2D 2E 2F 2G
Proposed Forebay and
Pump Station
EL 650Proposed Desalination
Facilities and Pump
Station
EL 60
150 MGD – EL 892
100 MGD – EL 767
50 MGD – EL 686
Ground Profile
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18. Capital Cost Summary
50 mgd Initial Phase
Plant
Site
Seawater
Intake
Desalination
Plant
Brine
Discharge
Conveyance
System
Total
MCTSSA $218 - $360 $670 - $698 $184 $328 $1,428 - $1,542
SRTTP $241 - $369 $636 - $663 $207 $317 $1,429 - $1,529
Based on supply integration into the untreated system.
Costs include oversizing buried project components for the 150 mgd ultimate capacity.
Costs in million $
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19. Cost Estimate Summary
Plant Production Capacity
50 mgd 150 mgd
Capital Costs (million$)
Desalination Plant 1,110 – 1,260 2,320 – 2,900
Conveyance 317 – 328 350 – 360
Annual O&M Costs (million$) 61 - 70 174 - 200
Total Unit Cost ($ per AF) 2,750 - 3,100 2,070 - 2,450
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20. Questions?
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