California Conference of Public Health OfficialsCalifornia Conference of Public Health Officials

July 23, 2009July 23, 2009

Monterey Regional Water Pollution Control AgencyMonterey Regional Water Pollution Control Agency

Recycled Water for Agriculture:A Case History in

Securing Grower Confidence

Seawater Intrusion FrontSeawater Intrusion Front180-Foot Aquifer180-Foot Aquifer

Groundwater exceeding 500 mg/L Chloride limit

Seawater Intrusion FrontSeawater Intrusion Front400-Foot Aquifer400-Foot Aquifer

Groundwater exceeding 500 mg/L Chloride limit

Independent analysisScientifically soundExpert reviewUse opposition

TransparencyCollaborationMonthly meetingsEducation

Competitive/ cost effectiveAdded value productHigh quality

Voluntary useOn-going extra monitoringSpecial studiesCrisis management support

GAINING GROWER ACCEPTANCEGAINING GROWER ACCEPTANCE

DATADATA

COMMUNICATIONCOMMUNICATION

VALUEVALUE

CUSTOMER SERVICECUSTOMER SERVICE

DATADATAMonterey Wastewater Reclamation Study for Agriculture (MWRSA )Monterey Wastewater Reclamation Study for Agriculture (MWRSA )

• 11 year study: 1976 to 198711 year study: 1976 to 1987

• 5 years of field testing5 years of field testing

• Independent monitoring:Independent monitoring: UC Davis and UC BerkeleyUC Davis and UC Berkeley

• Team included state, Team included state, local health officials, and ag local health officials, and ag

stakeholdersstakeholders

• Pathogen, soil, plant Pathogen, soil, plant tissue analysistissue analysis

FIELD RESEARCH RESULTSFIELD RESEARCH RESULTS

Conclusion: Conclusion: Food Crops Safe To Be Eaten UncookedFood Crops Safe To Be Eaten Uncooked

No viruses detectedNo viruses detected

99.999% removal of seeded virus99.999% removal of seeded virus

No negative field worker health effectsNo negative field worker health effects

Heavy metals not detectedHeavy metals not detected

Crop yields increasedCrop yields increased

Crop quality unaffectedCrop quality unaffected

Secondary TreatmentOcean outfall 2 miles250,000 population

Regional TreatmentPlant (RTP)

1989

New water supply for 19,450 AFY

2-PHASE IMPLEMENTATION

3° TREATMENTSalinas Valley Reclamation

Project (SVRP)

Monterey County Water Recycling Projects

1997

DISTRIBUTIONCastroville Seawater

Intrusion Project (CSIP)

Title 22 – Cl2 Disinfection

Unrestricted use12,080 Acres

45 miles pipeline

MRWPCA Service AreaJPA with 12 members

Food Safety Study, 1997-1998Food Safety Study, 1997-1998

Efficacy of Pathogen RemovalEfficacy of Pathogen RemovalStudy 1997-2003Study 1997-2003

• SalmonellaSalmonella• CyclosporaCyclospora• E. ColiE. Coli 0157:H7 0157:H7• LegionellaLegionella• GiardiaGiardia• CryptosporidiumCryptosporidium• Fecal Coli, Turbidity, Cl ResidualFecal Coli, Turbidity, Cl Residual

Results:

No viable microbes of public health concern in recycled water

COMMUNICATIONCOMMUNICATIONMaximizing Perceived SafetyMaximizing Perceived Safety

● Transparency Transparency ● Web data access● Grower webpage – daily updates

● CollaborationCollaboration● Community leaders, ag industry,

regulators & staff● Monthly meetings

● Education & outreachEducation & outreach● Tours● School programs● Civic and professional group talks● Exhibits● Newsletters

Build and maintain trust

Collaboration ResultsCollaboration Results Reasonable site labeling

CUSTOMER SERVICE• Voluntary UseVoluntary Use• Additional StudiesAdditional Studies

• 3° Filter flow rate increase 50%• Soil salt monitoring 8+ years• Endocrine disrupting compounds

• On-going Data CollectionOn-going Data Collection• Agronomic• Food safety

• Crisis Management SupportCrisis Management Support

95% use project water

September 2006

Spinach E. coli Incident

CNN arrives:

What’s the story?

VALUEVALUE

Quality assured water at reasonable cost

Monitoring includedMonitoring included

Nutrients (N, K, P)Nutrients (N, K, P)

Competitive costCompetitive cost

Title 22 Water Title 22 Water RecyclingRecycling

For “For “Unrestricted Use”Unrestricted Use”

1. Primary1. Primary – gravity – gravity• 70-75% solids removed70-75% solids removed

2. Secondary2. Secondary – biological – biological• 95% solids removed95% solids removed

3. Tertiary3. Tertiary – chemical filtration – chemical filtration• Alum polymer flocculationAlum polymer flocculation• Filtration – anthracite, sand, gravelFiltration – anthracite, sand, gravel• Disinfection - 2 hrs, ClDisinfection - 2 hrs, Cl22

• < 98% solids removed< 98% solids removed

2000 California Water Recycling Criteria- Agricultural Uses -

Type of UseTotal Coliform Requirements

Treatment Required

Irrigation of fodder, fiber & seed crops, processed food crops, pasture for non-milking animals, orchards & vineyards (no contact with edible portion of crop)

None specified • Secondary

Irrigation of pasture for milking animals

23/100 mL• Secondary• Disinfection

Irrigation of food crops (no contact with edible portion of crop)

2.2/100 mL• Secondary• Disinfection

Irrigation of any food crop where reclaimed water comes in contact with the edible portion of the crop, including root crops

2.2/100 mL• Secondary• Filtration• Disinfection

● Daily avg flow < 29.6 MGDDaily avg flow < 29.6 MGD

● Constituent limits:Constituent limits:

- - BOD5 (mg/L)BOD5 (mg/L) 10 10 25 25 2.4 2.4

- Turbidity (NTU)- Turbidity (NTU) 2 2 5 5 1.5 1.5

- Suspended Solids (mg/L) - Suspended Solids (mg/L) 10 10 25 25 3.5 3.5

- Settleable Solids (mL/L/hr) -- - Settleable Solids (mL/L/hr) -- 0.1 0.1 < 0.1 < 0.1

- Total Dissolved Solids (mg/L) -- 1,500- Total Dissolved Solids (mg/L) -- 1,500 859 859

- Total Coliform (MPN/100mL) 2.2 - Total Coliform (MPN/100mL) 2.2 23 23 100%100% ComplianceCompliance

(Weekly Median)(Weekly Median) (in no more than (in no more than 1 sample/month)1 sample/month)

RWQCB – MRWPCA Permit RequirementsRWQCB – MRWPCA Permit Requirements Recycled Water Recycled Water

ConstituentConstituent MeanMean MaxMax 2008 avg2008 avg

MONITORING PROGRAM 2008 MONITORING PROGRAM 2008 Red – Regulatory Requirement Red – Regulatory Requirement Yellow – Irrigation Suitability Yellow – Irrigation Suitability White – Food SafetyWhite – Food Safety

  Tertiary Plant DISTRIBUTION SYSTEM

CONSTITUENTSRecycled

WaterStorage Pond

Supplemental Wells (21)

Monitoring Stations (9)

Turnouts(112)

Metals & Organics YearlyYearly ---- ---- ---- ----

Agronomic & Salinity Bi-WeeklyBi-Weekly ---- YearlyYearly ---- ----

TDS Bi-WeeklyBi-Weekly ---- YearlyYearly

Specific Conductance DailyDaily DailyDaily YearlyYearly Continuous Continuous 5/wk5/wk

pH DailyDaily DailyDaily YearlyYearly WeeklyWeekly 5/wk5/wk

Total Suspended Solids DailyDaily ---- ---- ---- ----

Turbidity ContinuousContinuous DailyDaily ---- WeeklyWeekly ----

Settleable Solids DailyDaily WeeklyWeekly ---- ---- ----

Total Organic Carbon WeeklyWeekly ---- ---- ---- ----

BOD WeeklyWeekly ---- ---- ---- ----

Chlorine Residual ContinuousContinuous ContinuousContinuous ---- ContinuousContinuous 5/wk5/wk

Total Coliform DailyDaily DailyDaily MonthlyMonthly DailyDaily 2/wk2/wk

Fecal Coliform DailyDaily DailyDaily ---- DailyDaily 2/wk2/wk

Generic E. coli DailyDaily DailyDaily MonthlyMonthly DailyDaily 2/wk2/wk

Total and Fecal Coliform(County Health) ---- Bi-WeeklyBi-Weekly

Parasites & viruses ---- 4/Yr4/Yr ---- ---- ----

Clostridium P. (Co Health)    Bi-WeeklyBi-Weekly ---- ---- ----

2008 2008 RECYCLED WATER QUALITYRECYCLED WATER QUALITY

Agronomic Water Quality* Agronomic Water Quality*

TDSTDS 863 mg/L863 mg/LSARSAR 4.8 4.8 pHpH 7.1 7.1 ChlorideChloride 257 mg/L257 mg/LSodiumSodium 171 mg/L171 mg/LTotal NitrogenTotal Nitrogen 38 mg/L 38 mg/L

* Grab samples

CONCEPT TO SALAD BOWLCONCEPT TO SALAD BOWL

DATADATA

COMMUNICATIONCOMMUNICATION

VALUEVALUE

CUSTOMER SERVICECUSTOMER SERVICE

Prove its safe

Get them to believe and trust.

How can they say NO?

Keep them happy

““Changing Wastewater To Safe Water”Changing Wastewater To Safe Water”

Karen HarrisCommunity Relations Specialist

(831) 645-4604karenh@mrwpca.com