GWRS Final Expansion
Project and SP-173 Update
GWRS Steering Committee Meeting
April 11, 2016
Groundwater Replenishment System
(GWRS) Projects
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GWRS Project (Completed 2008)
– Construction of 70 MGD Treatment Facility with future expansion
capacities, Injection Wells, and Pipeline
GWRS Initial Expansion (Completed 2015)
– Expansion of 70 MGD Treatment Facility to 100 MGD including SEFE
pump station & storage tanks
GWRS Final Expansion (Completion TBD)
– Expansion of 100 MGD Treatment Facility to 130 MGD including water
supply pipeline, EQ tanks, pump station & treatment process
reconfigurations at OCSD
GWRS – Advanced Water Treatment Facility
(AWTF) Improvements
Three New
UV Trains
Six New RO Units
Microfiltration West
Bldg Expansion
(1.5 new trains)
New Decarbonator
and Cartridge Filter
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New Product Water and
BW Supply Pumps
GWRS Source Water
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To produce 130 MGD of GWRS water – approximately 174 MGD of Secondary
Effluent is required from OCSD (including 4 MGD of GAP source water)
OCSD combined Plant No. 1 & Plant No. 2 total influent flows are currently 182
MGD
Santa Ana Regional Interceptor (SARI) discharges to OCSD Plant No. 2 are
currently ~30 MGD
OCWD is currently not permitted to use SARI source water for GWRS by the
Division of Drinking Water (DDW)
GWRS Expert Panel initial evaluation of recycling SARI water through GWRS
deemed feasible with recommendations. DDW will have to provide approval
and conditions for SARI to be recycled.
OCSD/GWRS Final Expansion Flows
Item
Current Plant No. 1 & 2 Influent
182 MGD
Segregated SARI Influent to Plant No. 2
-31 MGD
OCSD Plant Water Usage
Total Flows Available for GWRS FE
149 MGD
-6 MGD
MF Backwash Waste Flows
16 MGD
OCSD 2-72 SARI WW Diversion Projects2
3-8 MGD
Preferred Influent for GWRS FE
Ave. GWRS FE
Produced1
-2 MGD
Segregated OCSD Sidestream Wasteflows (NDMA)
Total Flows Available for GWRS FE3
1)
2)
3)
Flow
111 MGD
162 - 167 MGD
120 - 125 MGD
174 MGD
130 MGD
Assumes 4 MGD Secondary Effluent for GAP and 85% RO Recovery;
Exact diversion flows are currently being evaluated by OCSD;
Potential additional source flows include Extraction Well Discharges, MF Cleaning Wastes, Additional SARI WW Diversions
GWRS Flows & Production
Project
GWRS Max
Daily Production
(MGD)
GWRS Yearly
Production
Goal
(AFY)
Average Daily
Production
Goal
(MGD)
GWRS
70
70,000
62.5
GWRS Initial
Expansion
100
103,000
92
GWRS Final Expansion
130
134,000
120
405 Freeway
OCWD GWRS Facility
OCSD Plant No. 1
Exist 66-inch
Pipeline to be
Rehabilitated
OCSD Plant No. 2
New EQ Tank
New Pump Station
GWRS Final Expansion Implementation Plan
Plant No. 1
Plant No. 2
GWRS Final Expansion
Preliminary Cost Estimate
Project Description
Cost (Millions)
OCWD AWTF Expansion to 130 mgd
$130
OCSD Plant No. 2 Pump Station
$18
OCSD Plant No. 2 Six MG Flow EQ Tank
$23
OCSD Slip Line existing OCSD pipeline w/ 58” HDPE
$37
OCSD Plant No. 2 Headworks SARI Segregation
$45
Total*
$253
*Represents total costs for OCWD. Planned OCSD & OCWD CIP Projects not included
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Initial Draft GWRS FE Project
Unit Cost Estimate
Financing Assumptions
Unit Cost ($/af)1
Melded Unit Cost
($/af)2
5% financing over 30 years
– no grants obtained
$980/af
$567/af
1% financing over 30 years
- $30 million of grants
$733/af
$509/af
1) Unit cost based on increased production of 31,000 af/year;
2) Melded unit cost combines current operating unit costs with GWRS FE
unit costs for total production of 134,000 af/year
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Next Steps
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Staff to review Draft SP-173 Implementation Report in May 2016
Final SP-173 Implementation Plan complete in July 2016
OCWD Complete CEQA & Engineer’s Report to establish project in August
2016 and pursue grant funding opportunities
OCSD present SP-173 findings to July Operations Committee Meeting
OCSD & OCWD to prepare amendment to joint agreement
– Implementation plan & each agencies responsibilities to be included
Initiate MF Pilot Studies at OCSD Plant No. 2 to evaluate water quality impacts
OCWD staff and GWRS Expert Panel will continue refining recommendations
for recycling SARI
End of Presentation