10/16/2025
1 RiversideCA.gov1
RiversideCA.gov
WATER TREATMENT APPROACH TO MEET PER-AND POLYFLUOROALKYL SUBSTANCES (PFAS) REGULATIONSCity CouncilOctober 28, 2025Riverside Public Utilities RiversideCA.gov2
OVERVIEW1. Groundwater Quality– RPU groundwater sources contain PFOS/PFOA levels above the newly adopted Federal drinking water standards.2. Treatment Costs– Achieving compliance will require advanced treatment, which is projected to be costly.3. Litigation Relief– Ongoing PFAS litigation settlements are expected to provide some financial relief, helping to offset a portion of treatment costs.4. Future Surcharge– A dedicated Water Treatment Surcharge will ultimately be necessary to ensure long-term compliance and funding stability. 1 2
10/16/2025
2 RiversideCA.gov3
OVERVIEW CONT.5. Recommendationa. Temporary Delay– Postpone implementation of the Water Treatment Surcharge at this time.b. Monitoring– Continue to monitor EPA’s actions regarding possible compliance extensions.c. Follow-Up– Provide a detailed report and updated recommendation to the Board of Public Utilities (BPU) within one year.
RiversideCA.gov4
BACKGROUND1. Designed to repel oil and water 2. Known as “forever chemicals”3. Bioaccumulate in living organisms4. Potential to cause adverse human and ecological health effects Per- and Polyfluoroalkyl Substances (PFAS) are human-made chemical compounds, a group of more than 12,000 substances of emerging contaminants of concern.3 4 10/16/2025
3 RiversideCA.gov5
LEGISLATIVE HISTORY 1. In May 2016, US EPA issued a lifetime health advisory for (PFOS) and(PFOA) for drinking water, to notify customers of the presence of levelsover 70 parts-per-trillion (ppt).2. In July 2018, State Water Resources Control Board, Division of DrinkingWater (DDW) established an interim notification level (NL) of 14 ppt forPFOA and 13 ppt for PFOS and a single response level (RL) of 70 ppt forthe combined concentrations of PFOA and PFOS.3. In August 2019, DDW revised the NL to 6.5 ppt for PFOS and 5.1 ppt forPFOA. RL remains at 70 ppt.4. On February 6, 2020, DDW issued updated drinking water RL of 10 ppt forPFOA and 40 ppt for PFOS based on a running four-quarter average.5. On March 5, 2021, DDW issued a drinking water NL of 500 ppt and RL of5,000 ppt for PFBS.
RiversideCA.gov6
LEGISLATIVE HISTORY CONT.6. On October 31, 2022, DDW issued a drinking water NL of 3 ppt and RL of 20 pptfor PFHxS.7. On March 14, 2023, US EPA proposed MCL’s for six (6) compounds: PFOA: 4 ppt,PFOS: 4 ppt, PFHxS 10 ppt, Gen X 10 ppt, PFNA 10 ppt and a Hazard Index (HI) notto exceed 1 for: PFNA, PFHxS, PFBS, and GenX (HI is made up of a sum offractions) with compliance by 2029.8. On May 14, 2025, the EPA announced its intent to extend compliance deadlinesfor PFOA and PFOS from 2029 to 2031. The rule promulgation process can takewell over 1-year to complete and, in some instances, rules are not implementedat the end of the process.9. On August 6, 2025, DDW discussed reducing NLs for PFOA and PFOS to 4 ppt, RLfor PFHxS to 10 ppt and creating a PFHxA NL at 1 ppb and RL of 10 ppb at theState Water Board meeting, which will likely be implemented in September 2025.10. DDW MCLs anticipated to be released in late 2025. 5 6
10/16/2025
4 RiversideCA.gov7
ACTIONS 1. On October 28, 2019, the Board of Public Utilities approved a PFASstudy.2. On May 23, 2022, the Board of Public Utilities received and filed anupdate on the Per and Polyfluoroalkyl Substances Updates.3. In November 2022, staff received the final report from the consultant,HDR, outlining a cost-effective and optimized long-term treatmentstrategy for reducing PFOA and PFAS.4. On November 14, 2022, staff presented the results of the PFAS removaldemonstration study at the Palmyrita Treatment Plant to the Board ofPublic Utilities.5. On June 12, 2025, staff presented a PFAS update to the Mobility &Infrastructure Committee.6. On July 28, 2025, staff presented a PFAS update to the Board of PublicUtilities.
RiversideCA.gov8
RPU GROUNDWATER WELLS1. Forty-Five groundwater wells extract water from the Riverside, Rialto Colton and Bunker Hill groundwater basins.2. Several wells are treated with GAC and/or IX to remove anthropogenic compounds.3. Three transmission mains convey the City's domestic groundwater to a 32-million-gallon central reservoir complex, where it receives final treatment via blending and disinfection before being delivered to customers.ௗ 7 8
10/16/2025
5 RiversideCA.gov9
WATER SAMPLES, BLENDING AND ALTERNATIVES1. Water samples from more than 30 wells exceed the existing Statenotification levels for PFAS.2. Treatment capacity is still capable of combining water sources to reducePFAS concentrations during low demand season, but in high waterdemand periods, it will exceed the PFAS Federal limits without additionaltreatment or turning off wells with high PFAS concentrations.3. Three (3) alternatives with two (2) commercially and readily available PFAStreatment technologies, Granulated Activated Carbon (GAC) and IonExchange (IX), were identified to reduce the concentrations as part of theHDR Study.
RiversideCA.gov10
GAC 20-Year Life Cycle Cost Estimate is Higher than that of IXIon ExchangeGranular Activated CarbonParameterAlt 3 –North Orange & JWNAlt 2 – North Orange & Palm MeadowsAlt 1 –RegionalAlt 3 –North Orange & JWNAlt 2 – North Orange & Palm MeadowsAlt 1 –Regional12,45410,85023,45812,45410,85023,458Design Capacity (gpm)$27 M$24 M$63 M$38 M$35 M$84 MCapital Cost$124 M$108 M$248 M$117 M$107 M$238 MNPV Total O&M$151 M$132 M$311 M$156 M$142 M$322 MTotal PV$1.15$1.16$1.26$1.19$1.24$1.30Annual $/kgal Treated9 10 10/16/2025
6 RiversideCA.gov11
WATER SOURCE COMPARISIONRiverside also considered utilizing imported water in lieu of local groundwater, but this was not a cost-effective solution. RPU RPU + PFAS Imported Water $0.00$200.00$400.00$600.00$800.00$1,000.00$1,200.00$1,400.00$1,600.00$1,800.00$ Water/AF RiversideCA.gov12
WATER SOURCE COMPARISION1. Cost for utilizing imported water as a blending sourcea. $40,000,000 to construct a pipeline from the delivery point to Linden Evans for blending waterb. $9,00,000 to purchase water annually for blending purposes at Tier 1 rates.c. Additional chlorination station, chemical costs and O& M.2. Operational Concernsa. Minimum flow 21,000 gpm needed for blending the current interconnect is rated for 13,500 gpmb. Nitrification from chloraminesc. Stranding of assets11 12 10/16/2025
7 RiversideCA.gov13
PFAS CONCENTRATION & COMPLIANCEThe data below compares PFAS concentrations at RPU’s drinking water compliance point to the Federal and State standards.HI(<100%)PFHxSPFNAPFBSGenXPFOSPFOAUnits in parts per trillion (ppt)35006.55.1CA Notification LevelND -5.5NDND - 4NDND -6.4ND -4.7Compliance Point (7th & Chicago) *101020001044Health-Based Value and EPA MCL0-61%0-61%0%0-0.002%0%Hazard Index (HI) in %*Data ranges 2019-current. SWRCB-DDW proposed MCLs are anticipated this year.
RiversideCA.gov14
PFAS REDUCTION NEEDED1. The analysis revealed that an additional local treatment plant on the Waterman transmission main would be needed in addition to the optimum alternative proposed by the consultant HDR.2. Staff also modified the Alternate 2 proposal to expand the current Palmyrita WTP, which will provide treatment on the North Orange transmission main. PFHxSPFOAPFOSUnits in parts per trillion(ppt)35.16.5CA Notification Level (NL)70%25%38%Percent Reduction to NL10*44EPA MCL21%31%62%Percent Reduction to MCL*PFHxS MCL is part of the Hazard Index (HI)The table below shows the amount of reduction needed to meet the regulations. 13 14 10/16/2025
8 RiversideCA.gov15
RPU WATER QUALITY POLICY1. On January 24, 2022, the Board of Public Utilities approved the DrinkingWater Quality Policy Principles.2. On February 22, 2022, the City Council adopted the Drinking WaterQuality Policy Principles.3. The nine water quality policy principles guide RPU in its compliance withdrinking water standards, as well as its coordination with Federal andState policies and agreements with responsible parties.4. RPU is actively collaborating with regulatory agencies, water associationworkgroups and has been evaluating and developing treatment optionsto reduce PFAS levels and meet regulatory requirements.
RiversideCA.gov16
PFAS SETTLEMENT PROCEEDS1. RPU's low water rates are a result of the City's success in mitigating higher treatment costs by successfully holding polluters responsible for groundwater contamination. Over the last 30 years, this effort has provided funding for five of the six water treatment plants to reduce contamination. 2. Currently, RPU expects to receive $39.6M in PFAS settlement proceeds manufacturers of PFAS over the next 8 years. A small portion of the settlement is pending final Court approval and may be adjusted when finalized.3. Establish a Water Treatment Designated Reserve for settlement proceeds to fund water treatment operating and capital costs.Estimated Settlement ProceedsFiscal Year$23,325,332FY 2025/26$8,127,588FY 2026/27$2,760,321FY 2027/28$1,521,195FY 2028/29$1,034,412FY 2029/30$1,034,412FY 2030/31$912,717FY 2031/32$851,869FY 2032/33$39,567,846Total15 16 10/16/2025
9 RiversideCA.gov17
DISCUSSION1. Compliance with the Federal PFAS MCLs is estimated to cost:2. Financing capital costs of treatment plants:O&M/Personnel Costs *Capital CostsYear in ServiceTreatmentPlant$4,431,000$27,000,000FY 2028/29 Plant #1$2,727,000$15,000,000FY 2029/30Plant #2$11,914,000$55,200,000FY 2030/31Plant #3$19,072,000$97,200,000Total*- Cost in FY 2030/31 when all 3 plants are online.Estimated Financing Costs - 30 YearsTreatment Plant Capital Funding$91,000,000100% Bond Financing ($97.2 million)$58,500,000Combination $35.7 million settlement proceeds and $61.5 million bond financing RiversideCA.gov18
FUNDING SOURCES1. Settlement Proceedsa. Anticipate receiving $39.6 from manufactures of PFAS2. Grantsa. $959,752 US Environmental Protection Agency’s and Tribal Assistance Grant Program application submitted 3. Additional Funding Sources to Considera. Continue to pursue settlements from responsible partiesb. Federal and State grant opportunitiesc. Other revenue including proceeds from surplus property sales17 18 10/16/2025
10 RiversideCA.gov19
COMMUNITY OUTREACHEvent/Community Group ExamplesGreater Riverside Chamber of Commerce (GRCC)Building Industry Association (BIA)Residents for Responsible Representation (RRR)Downtown Area Neighborhood Alliance (DANA)Mission Grove Neighborhood AssociationNeighbors of the Wood Streets (NOWS)Neighbors Better Together (NBT)City Sponsored Events at Community Centers such as Orange Terrace CenerBallroom, La Sierra Senior Center Ballroom, and Bobby Bonds/Cesar ChavezCommunity Cener Auditorium1. Attend Event/Community Group Meetings, Social Media and Webpage2. Public Hearing notice on website and direct mailed to customers for City Council(Prop 218 Compliance) RiversideCA.gov20
40WHAT’S NEXTDateActionJune 12, 2025Mobility & Infrastructure Committee UpdateJuly 28, 2025Board of Public Utilities UpdateSeptember 8, 2025Board of Public Utilities Cost of Service and Rate ResultsOctober 28, 2025City Council Cost of Service and Rate ResultsJune 22, 2026Board of Public Utilities UpdateJuly 28, 2026City Council UpdateTo Be DeterminedCommunity OutreachTo Be DeterminedBoard of Public Utilities Public Hearing and ConsiderationTo Be DeterminedCity Council Public Hearing and ConsiderationJuly 1, 2027Proposed Effective Date 19 20
10/16/2025
11 RiversideCA.gov21
WATER QUALITY INFORMATION•Riverside’s water meets or exceeds all Federal and State Regulations •The Annual Water Quality report is available online at RiversidePublicUtilities.com/WQR •The Groundwater Atlas is also available atRiversidePublicUtilities.com/Reports RiversideCA.gov22
OVERVIEW RECAP1. Groundwater Quality– RPU groundwater sources contain PFOS/PFOA levels above the newly adopted Federal drinking water standards.2. Treatment Costs– Achieving compliance will require advanced treatment, which is projected to be costly.3. Litigation Relief– Ongoing PFAS litigation settlements are expected to provide some financial relief, helping to offset a portion of treatment costs.4. Future Surcharge– A dedicated Water Treatment Surcharge will ultimately be necessary to ensure long-term compliance and funding stability. 21 22
10/16/2025
12 RiversideCA.gov23
That the City Council:1. Receive the cost of service and rate design study results andrecommendations for water treatment facilities to meet Per-and Polyfluoroalkyl Substances (PFAS) regulations;2. Approve establishing a Water Treatment Designated Reserve inthe Water Utility Fund to set aside proceeds received from PFASsettlements to fund capital costs for water treatment plants;RECOMMENDATION RiversideCA.gov24
Treatment Facility no. 1, Ion Exchange (IX) WTP3. Recommend staff offset the capital cost of the water Treatment Facility no. 1, utilizing an Ion Exchange (IX) WTP, to meet PFAS regulations with PFAS settlement proceeds;4. Receive an update on RFP No. 2415 for Design andConstruction Management services for the first PFAS treatmentplant, Treatment Facility No. 1, using an Ion Exchange (IX) WTP,and recommend staff return with an update on project designand timeline; andRECOMMENDATIONS CONT.23 24 10/16/2025
13 RiversideCA.gov25
Treatment Facilities nos. 2 and 35. Recommend staff return to the Board of Public Utilities forreview of a Water Treatment Surcharge within one year forwater treatment facilities, not covered by PFAS settlementproceeds, to meet Per- and Polyfluoroalkyl Substances (PFAS)regulations.RECOMMENDATIONS CONT.
RiversideCA.gov26
ABBREVIATIONS & ACRONYMS •$/kgal Dollar per 1,000 gallons•ACWA Association of California Water Agencies •AWWA American Water Works Association•CA California•DBCP Dibromochloropropane•DDW Division of Drinking Water a division of the SWRCB•EPA Environmental Protection Agency - Federal regulatory agency •GAC Granular activated carbon •Gen X Trade name for a processing aid technology used to make high-performance fluoropolymers•GPM Gallons per minute •HFPO-DA Hexafluoropropylene oxide dimer acid •HI Hazard index•IX Ion exchange •JWN John W. North •MCL Maximum contaminant level •NL Notification level •NPDWR National primary drinking water regulation 25 26
10/16/2025
14 RiversideCA.gov27
ABBREVIATIONS & ACRONYMS •NPV Net present value (estimated in 2022)•O&M Operation & Maintenance•PFAS Per and polyfluoroalkyl substances•PFBS Perfluorobutane sulfonic acid•PFHxS Perfluorohexane sulfonic acid•PFNA Perfluorononanoic acid•PFOA Perfluorooctanoic acid•PFOS Perfluorooctane sulfonic acid•PPB Parts per billion•PPT Parts per trillion•PV Present value (estimated in 2022)•RFP Request for proposals•RL Response level•RPU Riverside Public Utilities•SWRCB State Water Resources Control Board - State regulatory agency•TCE Trichloroethene•TM Transmission main•WTP Water treatment plant27