Water Reuse for Augmentation of Water SupplyJoseph G. Jacangelo1,2Tamar S. Levenberg1James DeCarolis11MWH2The Johns Hopkins University

Your Drinking Water: Challenges and Solutions for the 21st CenturyApril 20-21, 2009

Presentation OverviewOverview and drivers for water reuse

Water quality and regulatory considerations for reuse

Contaminant exposure routes

Advanced treatment for selected constituents of concern

Summary: Future trends in water reuse

What is Water Reuse?

The reclamation and treatment of impaired waters for the purpose of beneficial reuse.

WateReuse Association, 2003

What is Water Reuse?

The reclamation and treatment of impaired waters for the purpose of beneficial reuse.

WateReuse Association, 2003

Impaired WatersMunicipal and industrial wastewater effluentBrackish waterPoor quality groundwaterAgriculture return flowsStormwater

What is Water Reuse?

The reclamation and treatment of impaired waters for the purpose of beneficial reuse.

WateReuse Association, 2003

What is Water Reuse?

The reclamation and treatment of impaired waters for the purpose of beneficial reuse.

WateReuse Association, 2003

Non-Potable Reuse Examples: irrigation and industrial reuseTypes of Water Reuse

Potable Reuse - includes drinking waterDirect potable reuseIndirect potable reuse

Uses of Reclaimed Water Agricultural irrigationLandscape irrigationNonpotable urban usesIndustrial usesImpoundmentsEnvironmental usesGroundwater rechargeIndirect potable reuse

Planned Engineered systems to provide augmentation of water supply

Types of Indirect Potable Reuse

Unplanned Withdrawal of water from water bodies that have received wastewater or other types of dischargesMississippi, Ohio, S. Platte riversThe magic of the river bed

Global Drivers of ReuseRising Water DemandsDemographic, economic growthUrban growthFinite Water ResourcesNearby sources: Rare & vulnerableRemote sources : Costly to developRegulatory & Political Pressure Effluent disposal (zero discharge)Environmental issues associated with impoundments (no dams)

Total Water PortfolioFreshwaterBrackish and SeawaterConservationGroundwaterReclaimed water

Current Status of Water Reuse in the United StatesApproximately 1,500 water reuse facilities in U.S.

Only 5-7% of wastewater is currently reused

I believe the Last River for us to tap is Wastewater. - John Keys, Commissioner USBR

Water Reuse BreakdownCaliforniaFloridaSource: US EPA. Guidelines for water reuse

Largest Water Reuse Programs in the United StatesOCWDCentral/West BasinMWDSan JoseLACSDSan Diego CountyIrvine RanchDublin San RamonEBMUDOrlandoScottsdale

PhoenixSan AntonioEl PasoTarrant RegionalSt. PetersburgPinellas CountyKing County (WA)AustinSanta RosaUOSA (VA)SNWA/LVVWD

Groundwater Recharge - Spreading

Groundwater Recharge - Injection

Upper Occoquan Sewage Authority, Virginia, Water Reclamation Plant 20 years of operation

Regulations and Guidelines Vary Depending on Type of ReuseIndirect Potable ReuseAgricultural Reuse on Food CropsUnrestricted Recreational ReuseUnrestricted Urban Irrigation ReuseRestricted Urban Irrigation ReuseRestricted Recreational ReuseIndustrial ReuseEnvironmental ReuseAgricultural Reuse on Non-food Crops

Reuse Applications and Number of States with Guidelines2004 Guidelines for Water Reuse, EPA/625/R-04/108

Type of ReuseNumber of StatesUnrestricted Urban28Restricted Urban34Agricultural (Food Crops)21Agricultural (Non-food Crops)40Unrestricted Recreational7Restricted Recreational9Environmental (Wetlands)3Industrial9Groundwater Recharge (Nonpotable Aquifer)5Indirect Potable Reuse5

Title 22 Requirements for Non Potable ReuseSecondary treatment

Filtration turbidity of 2 NTU

2.2 total coliforms/100 mL

CT = 450 mg/L-min

Requirements for Indirect Potable ReuseSecondary and advanced treatment

Drinking water regulations

Monitoring of other constituents of concern (TOC, nitrogen, phosphorus, EDCs/PPCPs

Environmental Buffer

Water Quality

Constituents of Concern in Water ReuseMicrobesOrganicsMetalsNutrients SaltDomesticUseCommercialUseIndustrialUseTo Wastewater TreatmentWaterSupply

Water Quality Issues That Effect End UseCooling TowersNutrients, TDS, suspended solids, chlorides, odor, hardness, bacteriologicalTextile MillColor, inorganics, chlorine, odorCement ManufacturersSuspended solids, inorganicsWetland EnhancementsNutrients

Water Quality Issues That Effect End Use

AgriculturalTDS, boron, chloride, chlorine, suspended solids

Toilets and Urinal FlushingSuspended solids, color, odor

Wetland EnhancementsNutrients

Indirect Potable ReuseDWR, EDCs/PPCPs, Others

Exposure to Contaminants of Concern

Selected Routes of Exposure to Reclaimed WaterDirect exposureContact from surfaces exposed to reclaimed waterAccidental ingestionConsumption of fruits and vegetables irrigated with reclaimed waterContact with aerosols from spray irrigation or cooling towersIngestion through indirect potable reuse

Indirect exposureImpact environmental matrices and affect the transport of pollutants (irrigation of soils overspray)

BacteriaVirusesProtozoaCampylobacterHepatitis AGiardiaEscherichia coliReovirusCryptosporidumSalmonellaCalicivirusEntameobaYersiniaEnterovirusMicrosporidiumVibrioCoxsackievirusLegionellaAdenovirusAeromonasEchovirusMycobacteriumPoliovirusShigellaPseudomonasImportant Waterborne Pathogens

Concentration Ranges of Selected Microorganisms Found in Raw WastewaterAdapted from NRC, 1998

Multiple Barrier Approach to Risk ManagementSource controlAppropriate treatment (multiple barriers)Storage, transmission and distribution protectionCross connection control / backflow prevention, pipe line separationProtection of usage areasWarning signs, buffer zones, cross connection control, end-user agreements, user notifications

MONITORING TO ASSURE BARRIERS ARE WORKING

Treatment for Contaminant Removal

Water Reuse Treatment Trains

Membrane Modules

Spiral Wound Membrane

UV Systems

Treatment for Inorganics(Membrane Bioreactor and Reverse Osmosis)

Sunrise Treatment Streams

MBRRO

Influent Wastewater Characterization

CompoundUnitsRangeAvgBio. Oxygen Demand (CBOD5)mg/L 90-480244Total Suspended Solids (TSS) mg/L26-240130Total Nitrogen (TN)mg/L7 -7840Total Phosphorus (TP)mg/L8 3322Total Phosphatesmg/L1 - 118

Removal of Suspended Solids

Removal of Total Nitrogen

Removal of Phosphates

Treatment for Microorganisms

Fecal Coliform Bacteria and Coliphage in MBR Effluent

Comparison of Microbial Inactivation or Removal Efficacy by Selected Disinfectants and Filtration ProcessesAdapted from Trussell, 1993

Treatment for Endocrine Disrupting Compounds (EDCs) and Pharmaceuticals and Personal Care Products (PPCPs)(Reverse Osmosis and UV Advanced Oxidation)

Endocrine Disrupting CompoundsEndocrine Disrupting Compounds are contaminants of emerging concern

Removal by conventional wastewater processes are often at low levels

Advanced treatment often required

Examples of EDC/PPCPs Steroids

ReclaimedWater Market(27,000 m3/day)Municipal Wastewater(114,000 m3/day)

WaterReclamation PlantAdvancedWater Treatment (AWT)WaterFiltration Plant

ReservoirToPotable SupplyFirstAqueduct Advanced Water Treatment (AWT) (61,000 m3/day)(361,000 m3/day)Others~ 28 month detention time

Advanced Water Treatment (AWT)

Advanced Water Treatment (AWT)

Removal of Selected Compounds by AWT

UnitsAWT Product WaterMCL or Notification LevelNitratemg/L-N1.610TTHMsug/L3801,4 Dioxaneug/L2.83NDMAng/L2.310

EDC/PPCP AWT Removal Results 1 n=1

Efficacy of Various Treatment TechnologiesSource: Modified from Snyder et al., 2003, Env. Eng. Sci., 20(5): 456.

Summary: Non-Technical Barriers to Indirect Potable Water ReusePublic/user perception and cultural issues Toilet to Tap Syndrome

Better documentation of economics of water reuse

Support by local authorities

Project funding

Is Direct Water Reuse in our Future? Question is being asked more and more by experienced users

Technical issue Risk of failureNo time to recover public health implicationsFew studies focusing on failure analysis

Perception Issues

Summary: Trends in Water ReuseDual systemsAcceptability of indirect potable reuseUV for disinfection and advanced oxidationMembrane processesDistributed water reuse facilities

Summary: Trends in Water ReuseRegulation development, including current regulationsIntegrated resource planningUser perception studiesWater reuse as a center for sustainable development

End

Legislation

LegislationAll waters regulated by the Safe Drinking Water ActPathogenic microorganisms, regulated chemicals, nitrogen compounds and unregulated chemicals are of concern.

Texas Direct Reuse RegulationsEffective 2-12-97Reuse of untreated effluent is prohibited (TNRCC 210.22(a))Food crops to be consumed raw cannot be spray irrigated (210.22(b))Reclaimed water cannot be utilized in a way that degrades groundwater quality (210.22(d))Storage ponds for reclaimed water cannot be located within the floodway (210.23(a))All initial holding ponds must be lined properly in accordance with 210.23(c,d), which are designed to prevent leaking into groundwaterIrrigators must apply reclaimed water efficiently and avoid excess application that might lead to runoff or percolation (210.24(a))Reclaimed water piping must be separated from potable water piping by a horizontal distance of 9 feet (210.25(c))

Microorganism Control RequirementsSecondary treatment Filtration 2 NTUDisinfection 2.2 total coliform MPN/100mLResidence time in the environmentSpreading 6 monthsDirect injection 12 months

Regulated Chemical ControlDrinking Water StandardsDeveloped as needed (occurrence) and only when health effects, detection method, and treatment are knownSet of DWS not sufficient for impaired sources or indirect potable reuse

Unregulated Chemical ControlMonitor for Priority Pollutants and Chemicals with Action Levels, Plus, this is a dynamic situationIndustrial practices changePharmaceutical prescription preferences changePublic perceptions changeChemicals may also be selected to be monitored for because their presence may indicate that other chemicals of similar characteristics or origin are present. These other chemicals may have a specific human health effect.

Nitrogen Compound ControlA total nitrogen standard of 5 mg/L is set because all forms of nitrogen could convert to nitrate or nitrite in the groundwater

Direct Reuse IssuesEquityEssentially, water reuse allows one user to delay the need to pursue additional resources while forcing another (or many others) to do so sooner rather than laterMoral equity is the basis for many legal statutesLegalDirect reuse has the potential to undermine the prior appropriation system by depriving some users of their allotted waterOne of these users is the environment

Direct Reuse Issues, cont.Financial/InstitutionalReuse projects require a substantial amount of capital, and must be a cost-effective optionCity of Phoenix and Palo Verde Nuclear Power PlantPUBLIC ACCEPTANCE/HEALTHReusing treated wastewater has a negative perceptionAlthough less scrutiny towards non-potable reuse, there are still areas where it is frowned uponAgricultural irrigation is still handled cautiously

Direct Water Reuse Issues, cont.Potable reuse is much higher risk, therefore water utilities, regulatory agencies, the scientific community and the public have stigmatized itProhibited in most statesPropaganda such as toilet-to-tap and sewage beveragePublic education and confidence in water utility competence are paramount

Indirect Reuse IssuesEconomic feasibilityRelates to equityReused water might not be put to the most economically efficient useShould profitability be a criteria for indirect reuse permits?MarketingCan a large water user, such as a municipality or industry, sell its treated effluent using the bed and banks of a river?

Potable ReuseDirect reuseThe form of reuse characterized by transport via pipes or canalsIndirect reuseThe use of natural water bodies (usually rivers/streams, but also lakes/reservoirs and aquifers) to transport and/or purify reclaimed water, also called bed and banks and ASR.

Increased CostAdditional TreatmentConveyance, Distribution and StorageAdditional MonitoringDecrease in water sales revenueCan be cost effective ifWater supply is of poor qualityWater supply does not meet demandAdvanced wastewater treatment already required

Water Quality Issues That Effect End UseAgricultureTDS, boron, chloride, chlorine, suspended solidsLandscaping / Single Family HomesTDS, boron, chloride, chlorine, SS, odorsToilets and Urinal FlushingSuspended solids, color, odorWater FeaturesNutrients, color

Ulu Pandan NE, Singapore Water PlantProcess Schematic

Murrumba Downs AWTP Process SchematicWWTP EFFLUENTPRODUCT WATER TANKAWTP BALANCE TANKMF FILTRATE TANKREVERSE OSMOSIS

MICROFILTRATIONAmmonium Sulphate & Sodium HypochloriteSodium HypochloriteAntiscalantSulphuric AcidLime Water & Carbon DioxideProduct Water to AmcorRO Concentrate to WWTP Outfall

GI AWTP Process Flow

SCENARIO 5 (2)

&A

&F&RPage &P

LAMELLA CLARIFIER

FLOC BLANKET

RECIR CLARIFIER

SUPERPULSATOR

FLAT BOTTOMED

SHALLOW BED FILTER

TWIN BED FILTER

PRESSURE FILTER

MEMBRANE

SINGLE BED FILTER

SUBMERGED MEMBRANE

STATIC MIXER

BAFFLE FLOCCULATOR

PADDLE FLOCCULATOR

MIXING TANK

CENTRIFUGE

PLATE PRESS

GBT

BELT FILTER PRESS

PICKET FENCE THICKENER

CONTACT TANK

PUMP

GAC FILTER

ARSENIC ADSORBER

MICRO-STRAINER

DISTRIBUTION CHAMBER

FLOW METER

QUALITY METER

MANUAL VALVE

MOTORISED VALVE

SLUDGE TANKER

SLUDGE HOLDING TANK

OPEN TANK

TURBINE

INLET SCREENS

UV DISINFECTION

PROCESS STREAM

ION EXCHANGE

CHEMICAL STREAM

PIPE FLOCCULATOR

CHEMICALSTREAMNUMBERS

STREAMNUMBERS

BOREHOLE

SAMPLE TAP

DUPLEX STRAINER

AERATOR

LAMELLA THICKENER

SAND TRAP

RIVER

SERVICE RESERVOIR

IMPOUNDING RESERVOIR

LAMELLA CLARIFIER

MEMBRANE

DENSADEG

TURBO LME

PRESSURE MEMBRANE

SINGLE MEDIA FILTER

DUAL MEDIA FILTER

CONCENTRATE

FROM GIBSON ISLAND WWTP

ACTIFLO

RAW WATER BALANCE

RO

UV

MF

NEUTRALISED CIP TO WWTP

PRODUCT WATER

FROM LUGGAGE POINT WWTP

=

=

MF FEED

CHLORAMINE

=

=

RO FEED

COAGULANT & pH ADJUSTMENT

TO RIVER OUTFALL

=

=

TREATED WATER

ANTI-SCALANT & pH ADJUSTMENT

H2O2

LIME & HYPO

CO2

THICKENER

=

=

SOLIDS BALANCE

=

=

SLUDGE HOLDING

CENTRIFUGE

CENTRATE TO WWTP

SUPERNATANT TO RAW WATER

****Water reuse is a high growth area, because of some deep-rooted drivers. At a macro/global scale, factors include

- Water demands- Finite accessible resources, examples in the US are Florida, California and Texas- Regulatory & political pressure***TREATMENT (Nonpotable)

Proven technology , conservative retrofit: Tertiary filtartion & disinfection of conventional II effluent.

That is the most common treatment, often implemented as retrofit of existing conventional WWTP.

No hi-tech, little R&D needed, extremely reliable, but expensive.

For new reclamation plants, innovative treatment trains exist, more compact and streamlined to operate, such as in particular : - MBR, for most high quality nonpotable applications- APT, for agricultural applications Control StreamMBR OnlyStream AMBR + ROStream BMBR + Chem P Removal***Uses the most indirect potable.

This is the overall project concept highlighted. You may want to use this slide alone to describe the project concept to cut the number of slides.

You can mention at this point that one of the critical tasks for the feasibility study is to come up with an adequate advanced treatment train for the project. This will be the focus of the rest of the presentation.Uses the most indirect potable.

This is the overall project concept highlighted. You may want to use this slide alone to describe the project concept to cut the number of slides.

You can mention at this point that one of the critical tasks for the feasibility study is to come up with an adequate advanced treatment train for the project. This will be the focus of the rest of the presentation.**For examples, Texas has thorough regulations for water reuse. Here are some examples

Examples from Singapore and Australia. *Queensland, AustraliaGibson Island, Queensland, Australia