Identifying the Best Potable Reuse Treatment Approach with the Triple Bottom Line in Mind 2015 Pacific Water Conference February 4, 2015 Joseph Zalla, P.E. CH2M HILL
Agenda Drivers for Potable Reuse Potable Reuse Treatment Approaches from Around the World Triple Bottom Line (TBL) Accounting Utility Survey TBL Costs for Potable Reuse Treatment Summary and Conclusions 2
Current Drivers for Potable Reuse Population growth Climate change and drought severity Regulations Community pressure Easy supplies have already been tapped 3
Current Drivers for Potable Reuse Why is there a trend in some areas to move away from non-potable reuse and towards potable reuse? Winter demands for non-potable reuse are often low, resulting in low reuse during winter months Non-potable demands often are geographically separated by large distances which results in very high pumping and piping costs When large nonpotable reuse customers are located far from the water reclamation plant, the total costs of nonpotable projects can be significantly greater than potable reuse projects, which do not require separate distribution lines. (2012 National Research Council (NRC) Report on Water Reuse) 4
Additional Drivers for Potable Reuse California Legislative Action: Senate Bill 918: CDPH must investigate and report on the feasibility of direct potable reuse by December 31, 2016 State Water Resources Control Board Recycled Water Policy established a goal to increase the use of recycled water by 1,000,000 acre-feet by 2020 and 2,000,000 acre-feet by 2030 California discharges 3.5 MAF/year of treated wastewater to the ocean Potable reuse must be implemented to reuse most of this water (non-potable reuse infeasible and too costly at this scale) California Water Reuse (acre-feet/yr) 3,000,000 2,500,000 2,000,000 1,500,000 1,000,000 500,000 0 2009 2020 2030 5
Additional Drivers for Potable Reuse Potable reuse uses less energy than importing water and seawater desalination Ocean desalination = 3,700 kwh/acre-ft State Water Project water (CA) = 3,500 kwh/acre-ft Colorado River water (CA) = 2,500 kwh/acre-ft Purified water (reuse) = 800-1,500 kwh/acre-ft WateReuseCalifornia and WateReuseResearch Foundation Direct Potable Reuse (DPR) Initiative Raising money to research DPR in CA Target is $6M (>$5M raised to date) 6
Potable Reuse Plants RO-Based (West U.S. and International) vs. GAC-Based (East and Central U.S) Western U.S. uses RO based approach (and SAT) East and Central U.S. uses GAC based approach Singapore uses RO based approach Queensland uses RO based approach
Potable Reuse: Treatment Train Examples GWRS RO Based Treatment (70 mgd) Courtesy of Jim Kutzie, OCWD UOSA (VA) GAC Based Treatment (54 mgd) Multiple barriers provided by each treatment train for removal of bulk organic matter, trace organics, and pathogens Disposal of RO concentrate required for Train #1 8
What are the Costs for Potable Reuse? Fit for Purpose Water: The Cost of Overtreating Reclaimed Water (WRRF-10-01) Level of treatment provided for potable reuse projects varies considerably around the world Drivers for level of treatment: Regulations Water quality of wastewater effluent Water quality goals End uses of treated water Public influence (governmental, non-governmental, advocacy groups) 9
What are the Costs for Potable Reuse? Research compares triple bottom line (TBL) costs of non-potable and potable reuse scenarios to guide treatment selection Cost Estimating Approach: Select treatment scenarios Identify TBL factors Conduct utility survey to calibrate costs Cost model development Estimate costs Compare treatment trains Financial Environmental Sustainable Solution Social 10
Potable Reuse Scenarios Examined SCENARIO 2A COAG+OZONE+BAC+GAC+UV Figure is WateReuse Research Foundation s Intellectual Property OPTIONAL FLOC/SED OZONE BAC GAC UV (DISINFECTION ONLY) RAW WATER RESERVOIR FOR DRINKING WTP WWTP Secondary Effluent COAGULANT O 3 Discharge To gravity thickening and centrifuge SCENARIO 2B MF/RO/UVAOP WWTP Secondary Effluent MICROFILTRATION MONOCHLORAMINE REVERSE OSMOSIS UVAOP RAW WATER RESERVOIR FOR DRINKING WTP Discharge BW Waste to WWTP Influent ANTISCALANT RO CONC. H2O2 LIME AND CO2 SALT DISPOSAL TO LANDFILL OR EVAPORATION PONDS OCEAN / SEWER DISPOSAL OR MECHANICAL EVAPORATION (BRINE CONCENTRATOR + BRINE CRYSTALLIZER) 11
Triple Bottom Line Factors Each of the water reuse treatment trains is compared in terms of its TBL costs and not simply those internal to the utility Economic costs Benefits to society Benefits to the environment The objective is to quantify the most significant factors in monetary terms to facilitate comparisons among alternatives on the basis of societal welfare 12
TBL Factors Direct TBL Effects (Controlled by the Water Utility) Financial Costs (Construction, Eng, Annual O&M) Environmental and Social Factors Energy Use Chemical Use Direct Air Emissions (e.g., GAC regeneration) Water Efficiency Upstream TBL Effects (Caused by the Water Utility, but controlled by another entity) Environmentaland Social Factors; Energy and Chemical Production GHGEmissions (CO 2, CH 4, N 2 O) Other Air Emissions (PM 2.5, NO x, SO 2 ) Impacts to water resources, surface water, land, etci Tables are WateReuse Research Foundation s Intellectual Property Downstream TBL Effects due to Byproducts Released by Water Utility Environmental and Social Factors Ecosystem Footprint(e.g., land requirements for residuals disposal) Residuals Disposal: GHG and other air emissions from transport Impacts to surface and ground waters Downstream TBL Effects to or by End Users due to Reclaimed Water Use Financial Costs (e.g., fertilizer adjustment, soil mgmt) Environmental and Social Factors Impactto vegetation and soil due to water quality (e.g., TDS, chloride, SAR) Pollutant loads to surface waters Pollutant loads to ground waters 13
Monetizing TBL Factors U.S. Interagency Working Group on the Social Cost of Carbon developed economic cost impacts caused by CO 2 e releases (CO 2, CH 4, N 2 O): Impacts include agricultural productivity, human health, damages caused by floods, and damages caused to ecosystems USEPA has developed economic cost impacts to human health caused by other air emissions (PM 2.5, NO x, SO 2 ) from electricity generation and truck traffic (e.g., chemical deliveries, residual disposal, etci) Parameter CO 2 e PM 2.5 (from elec.) NO x (from elec.) SO 2 (from elec.) Cost $0.012/ pound $68.44 / pound $2.74 / pound $18.43 / pound Note: Costs shown are based on a 3% discount rate Table is WateReuse Research Foundation s Intellectual Property 14
Utility Survey Extensive data collected from 21 full-scale operational reuse plants Plants selected to match treatment scenarios analyzed (5, 20 and 70 mgd) Plant capacities ranged from 3 mgd to 100 mgd Operational costs include all annual O&M costs Labor, power, chemicals, residuals disposal, major equipment replacement, maintenance, etci 15
Cost Model Calibration (70 mgd) $9,000,000 Total Annual Costs $8,000,000 $7,000,000 $6,000,000 $5,000,000 $4,000,000 $3,000,000 $2,000,000 Cost Model Plant #4 $1,000,000 $- Power Costs Chemicals Maintenance & Repair Labor Major Equip Replacement & Other Costs Figures are WateReuse Research Foundation s Intellectual Property 16
Cost Model Calibration (70 mgd) Total Annual Costs $9,000,000 $8,000,000 $7,000,000 $6,000,000 $5,000,000 $4,000,000 $3,000,000 $2,000,000 $1,000,000 $- Figures are WateReuse Research Foundation s Intellectual Property Total Construction Cost Cost Model Plant #4 $450,000,000 $400,000,000 $350,000,000 $300,000,000 $250,000,000 $200,000,000 $150,000,000 Power Costs Chemicals Maintenance $100,000,000 & Repair $50,000,000 $0 Labor Major Equip Replacement & Other Costs Cost Model (2012) Plant #4 (2004 bid cost) Plant #4 (2012 escalated cost) 17
What are the TBL Costs? SCENARIO 2A COAG+OZONE+BAC+GAC+UV Figure is WateReuse Research Foundation s Intellectual Property OPTIONAL FLOC/SED OZONE BAC GAC UV (DISINFECTION ONLY) RAW WATER RESERVOIR FOR DRINKING WTP WWTP Secondary Effluent COAGULANT O 3 Discharge To gravity thickening and centrifuge SCENARIO 2B MF/RO/UVAOP WWTP Secondary Effluent MICROFILTRATION MONOCHLORAMINE REVERSE OSMOSIS UVAOP RAW WATER RESERVOIR FOR DRINKING WTP Discharge BW Waste to WWTP Influent ANTISCALANT RO CONC. H2O2 LIME AND CO2 SALT DISPOSAL TO LANDFILL OR EVAPORATION PONDS OCEAN / SEWER DISPOSAL OR MECHANICAL EVAPORATION (BRINE CONCENTRATOR + BRINE CRYSTALLIZER) 18
$400,000,000 $350,000,000 $300,000,000 Capital Costs MF/RO/UVAOP (evap ponds) MF/RO/UVAOP (mech evap) MF/RO/UVAOP (Ocean Disposal) $250,000,000 $200,000,000 $150,000,000 Floc/Sed/O3/ BAC/GAC/UV $100,000,000 $50,000,000 $0-10 20 30 40 50 60 70 80 Plant Capacity (MGD) Figure is WateReuse Research Foundation s Intellectual Property 19
Annual O&M Costs $20,000,000 $18,000,000 $16,000,000 MF/RO/UVAOP (mech evap) MF/RO/UVAOP (evap ponds) MF/RO/UVAOP (Ocean Disposal) $14,000,000 $12,000,000 $10,000,000 Floc/Sed/O3/ BAC/GAC/UV $8,000,000 $6,000,000 2-year GAC Replacement 8-year GAC Replacement $4,000,000 $2,000,000 $0 0 10 20 30 40 50 60 70 80 Plant Capacity (MGD) Figure is WateReuse Research Foundation s Intellectual Property 20
$1,400,000 $1,200,000 $1,000,000 Greenhouse Gas Costs (CO 2, CH 4, N 2 0) MF/RO/UVAOP (mech evap) MF/RO/UVAOP (evap ponds) MF/RO/UVAOP (Ocean Disposal) $800,000 $600,000 $400,000 $200,000 Floc/Sed/O3/ BAC/GAC/UV 8-year GAC Replacement $- 2-year GAC Replacement 0 10 20 30 40 50 60 70 80 Plant Capacity (MGD) Figure is WateReuse Research Foundation s Intellectual Property 21
$6,000,000 $5,000,000 $4,000,000 $3,000,000 Other Air Emissions Costs (PM 2.5, SO 2, NO x ) MF/RO/UVAOP (mech evap) MF/RO/UVAOP (evap ponds) MF/RO/UVAOP (Ocean Disposal) $2,000,000 $1,000,000 Floc/Sed/O3/ BAC/GAC/UV $- 0 10 20 30 40 50 60 70 80 Plant Capcity (MGD) Figure is WateReuse Research Foundation s Intellectual Property 22
$6,000,000 $5,000,000 $4,000,000 $3,000,000 $2,000,000 $1,000,000 Other Air Emissions Costs (PM 2.5, SO 2, NO x ) MF/RO/UVAOP (mech evap) MF/RO/UVAOP (evap ponds) Scenario Power Chemical CO 2 e Other Air (20 mgd) Consumption Consumption Emissions Emissions GAC-Based (MWh/yr) 4,400 (dry tons/yr) 1,770 (ton/yr) MF/RO/UVAOP (ton/yr) 2,900(Ocean Disposal) 11 RO-Based (w/ ocean disposal) RO-Based (w/ mech evap) 16,000 1,860 13,400 30 65,400 3,020 44,200 150 Floc/Sed/O3/ BAC/GAC/UV $- 0 10 20 30 40 50 60 70 80 Plant Capcity (MGD) Figure is WateReuse Research Foundation s Intellectual Property 23
TBL Life-Cycle Cost Comparison Potable Reuse Treatment 30-year net present value (NPV) calculated at 20 mgd plant capacity; 2012 US Dollars at 3% discount rate NPV Category GAC- Based RO-Based (with Ocean Disposal) RO-Based (with Mech. Evap) Financial NPV (Capital and O&M costs) $161 M $220 M $358 M EnvironmentalNPV (Monetized GHGs and Other Air Emissions) $12 M $47 M $175 M Total NPV $173 M $267 M $533 M Other non-monetized environmental factors (e.g., footprint, landfill disposal, etci) not listed, although can be significant 24
Major Conclusions for Identifying the Best Potable Reuse Treatment Approach with TBL in Mind Different treatment approaches have successfully been used throughout the U.S. and around the world Water quality concerns that impact treatment: TDS: High TDS may require blending of waters, full or partial RO treatment Disposal of RO concentrate can be challenging because of high TDS Organics (TOC, CECs): Multiple technologies can provide barriers (SAT, RO, UVAOP, ozone, BAC, GAC) Total Nitrogen: Biological nutrient removal at WWTP preferred Excellent pretreatment to MF/RO and lowers TN that alternative treatment approaches (e.g., O3/BAC/GAC/UV) do not remove 25
Major Conclusions for Identifying the Best Potable Reuse Treatment Approach with TBL in Mind Costs from WRRF Project 10-01: GAC-based approach has the lowest TBL cost for all flows analyzed At low flows (< 5 mgd) the financial cost of RO with ocean disposal is within range of GAC Only true for ocean disposal Gap widens with inclusion of environmental costs Differences in costs increase significantly at flows > 5 mgd At 70 mgd the capital cost alone is $360M for RO versus $210M for GAC 26
Major Conclusions for Identifying the Best Potable Reuse Treatment Approach with TBL in Mind Costs from WRRF Project 10-01 (cont d): Concentrate handling costs make RO cost prohibitive at inland locations where sewer disposal is not available RO may be required in closed or semi-closed watersheds where cycling up of salts could be problematic Recommend partial RO or blending with other water supplies to manage salts if possible More detailed information included in WRRF-10-01 report Released in March 2014 Includes non-potable treatment analysis 27
Acknowledgements WateReuse Research Foundation: Jimena Pinzon - Project Manager Project Team: Larry Schimmoller/CH2M HILL Dr. Mary Jo Kealy/CH2M HILL Dr. Karl Linden/University of Colorado Dr. Bill Bellamy/CH2M HILL Sally Williamson/CH2M HILL Jim Lozier/CH2M HILL Jason Smesrud/CH2M HILL Matt Ridens/CH2M HILL Josh McIlwain/CH2M HILL Project Advisory Committee: Albrey Arrington, Loxahatchee River District, FL Tom Chesnutt, A & N Technical Services, Inc. Philippe Gislette, CIRSEE Suez Michelle Chapman, United States Department of Interior, Bureau of Reclamation Robert Raucher, Stratus Consulting Dave Richardson, RMC Water and Environment Participating Utilities: Brian Good, Denver Water David Derkenne, Hunter Water Lachlan King, Hunter Water Clare McAuliffe, Melbourne Water Monica Gasca, Los Angeles County Sanitation Districts Theresa Slifko, formerly with Los Angeles County Sanitation Districts Bob Angelotti, Upper Occoquan Service Authority Paul Fu, Water Replenishment District of Southern California Irazema S. Rojas, El Paso Water Utilities Mehul Patel, Orange County Water District Robert Harris, Gwinnett County April Chan, City West Water Chris Arabatzoudis, City West Water 28
Acknowledgements CH2M HILL gratefully acknowledges the WateReuse Research Foundation s financial, technical, and administrative assistance in funding and managing the project through which this information was discovered Questions? Joseph.Zalla@ch2m.com 29