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Overview
• What is reclaimed water?
• How can reclaimed water be used?
• Identify benefits & concerns of water recycling
• Discuss additional water sources for reuse
World Freshwater Resources• 75% of Earth’s surface is
covered in water
• 2.5% of water is freshwater
– 75% locked in glaciers/permanent snow cover
– 0.3% of water is surface water
Future Water Demand in Arizona• Increasing human populations
are changing the Arizona landscape drastically
– 2nd fastest growing state
– 20% population increase 2000-2006
– Projected 25% additional increase by 2015
• Increased Water Demand– Residential– Commercial– Agricultural
Uses of Water• Municipal
– Human consumption (primary)
– Landscape irrigation– Fire protection
• Industrial– Factories/Refineries– Power Plants
• Agricultural – Irrigation– Livestock– Human consumption
(secondary)
• Environmental– River habitat maintenance– Human consumption
(secondary)
The Great Water Balancing Act
Environmental
Municipal
Agricultural
Industrial
Available Water
How much water do you use?Of the total quantity of
drinking water supplied to residential
homes in Arizona
greater then %
of a residence's total water consumption is for outdoor water use.
65
What are viable options for extending the water supply?
Reclaimed Water
• Reclaimed water is treated wastewater that can be used for irrigation and other non-potable uses to extend our water supplies.
Purple is the color code for reclaimed water!
A separate distribution system built of purple pipes
transports reclaimed water to sites where it will be used.
Reuse Options• Urban
• Industrial
• Agriculture
• Environmental and Recreational
• Groundwater Recharge
• Augmentation of Potable Supplies
Reclaimed Water In Arizona• Treated wastewater use in Phoenix
– 55% is directly reused– 16% is recharged for long term– 71% is actively reused or utilized
• Chandler’s Intel • Tempe’s SRP Kyrene Power plant• Palo Verde Nuclear Power plant• Tres Rios Wetlands (Phoenix)
• Currently 8% of Tucson Water’s total demand is met with reclaimed water
• City of Maricopa
Reclaimed Water Benefits
• Reduces demand on drinking water supplies
• Reduces disposal into waterways, which can help reduce nutrient loads in surface waters
• Reduces fertilizer use, as some nutrients like nitrogen and phosphorus remain
Reclaimed Water Quality Concerns• Safety of reclaimed water
– Quality regulated by USEPA and ADEQ – Different water quality classes of reclaimed water (C, B, B+, A, A+)
• Safety of infrastructure – Identified by the color purple – Dye tests to ensure there is no
cross-connection between potable and reclaimed systems
• Public Perception – ‘Yuck’ Factor– Education is key – Prevent Toilet to Tap headlines
• Is it clean enough? – Pharmaceuticals, personal care products, EDC’s, microorganisms etc. – Questions remain about accidental ingestion posing health concern for humans
How do we combat these concerns?
• Waste Water Treatment Facilities treat water to extremely high standards
• Various processes are utilized in order to remove and harmful contaminants and disinfect any microorganisms that may be present
• The majority of Recycled water produced in Arizona is considered A+ grade quality
Arizona Reclaimed Water Classifications
Water Quality Class
Requirements
Class A+ a. The 24-hour average turbidity is two NTU or less. b. There are no detectable fecal coliform organisms. c. A+ reclaimed water has been denitrified so as not to exceed 10 mg/L total
nitrogen.
Class A a. The 24-hour average turbidity is two NTU or less. b. There are no detectable fecal coliform organisms. c. Includes requirements for nitrogen management and lining of impoundments.
Class B+ a. The concentration of fecal coliform organisms is less than 200 CFU/100 ml. b. B+ reclaimed water has been denitrified so as not to exceed 10 mg/L total
nitrogen.
Class B a. The concentration of fecal coliform organisms is less than 200 CFU/100 ml.b. Includes requirements for nitrogen management and lining of impoundments.
Class C a. The concentration of fecal coliform organisms less than 1000 CFU/100 ml.b. Includes requirements for nitrogen management and lining of impoundments.
Surface Water vs. Reclaimed Water Regulations
Surface Water• The specific level for full
body contact (swimming) is 235 CFU/100ml E.coli.
• Water-quality criteria for recreational water quality were established by the USEPA based on a target risk level of – 8 cases of gastrointestinal
illness per 1,000 swimmers per year.
Reclaimed Water• The specific level Class A
reclaimed water that is used for irrigation is 0 CFU/100mL E.coli.
• The specific level Class B reclaimed water that is used for irrigation is 200 CFU/100mL E.coli.
1. Screens remove plastics, and other non-
biodegradables while sand and grit settles
3. Aerobic treatment uses dissolved oxygen to promote the growth of biological floc that substantially removes
organic material
4. Clarification is used to settle out the biological floc
and produce water containing very low levels of
organic material and suspended matter
5. Disinfection use chlorine or UV light to inactivate any
microorganisms present
2. Primary clarification allows solids or “sludge” to settle out of the water while
floating material such as grease and oils can rise to
the surface and be skimmed
6. Filtration uses filters to “finish” the water by
removing small particles
FILTRATION
Reclaimed Water Permits
020406080
100120140160180200
Class A+ Class A Class B+ Class B Class C
Michele Robertson, ADEQ
Potential Uses• It can be used for:
– Irrigation – Street-sweeping operations – Power generation – Decorative fountains – Fire protection (purple fire hydrants) – Dust control – Aquifer recharge – Cooling or makeup water for a variety of industrial processes – Natural system restoration
• It can’t be used for:– Body-contact recreation (including swimming pools) – Cooking or drinking
GRAY WATER
reuse
DISCHARGEDto dry river bed
Central Arizona Project water
Further treatment
Water treatment
CommunityGround water
Wastewater treatment: primary +secondary
BIOSOLIDS:land application
EFFLUENTCROPIRRIGATION
RECLAIMED WATER
for landscape irrigation
ArizonaWaterReuse
Water Reuse Options• Direct Reuse:
– for crops (effluent)– Dual Distribution Systems can be used to supply potable and
reclaimed water via two separate distribution lines
• Indirect Reuse:– treated wastewater recharged to a groundwater aquifer via soil-
aquifer treatment – e.g., Tucson, AZ ~ 50 mgd put into the Santa Cruz dry river
bed
• Direct Potable Reuse:– wastewater treated and directly supplied for all uses including
potable water (rarely done)
Current water distribution systems
Future water distribution systems
What’s in Reclaimed Water?• Number and concentration of constituents highly
variable, depending on:– Type and level of treatment provided– Source control– Commercial and industrial waste input– Disease in the community
• Few to immeasurable levels of microbial pathogens for tertiary treated reclaimed water
• Many chemical constituents in product water– Non-potable reuse – tertiary effluent “safe” from health
standpoint– Potable reuse – need additional water treatment
Summary of Water Quality Parameters of Concern for Water Reuse
Parameter� Range�in�Secondary�Effluents� Treatment�Goal�in�Reclaimed�Water� US�EPA�Guideline�
Suspended�solids� 5�mg/L�� 50�mg/L� <5�mg�SS/L�� 30�mg�SS/L� �
Turbidity� 1�NTU�� 30�NTU� <0.1�NTU�� 30�NTU� 2�NTU�BOD5� 10�mg/L�� 30�mg/L� <10�mg�BOD/L�� 45�mg�BOD/L� 10�mg/L�COD� 50�mg/L��150�mg/L� <20�mg�COD/L�� 90�mg�COD/L� �TOC� 5�mg/L�� 20�mg/L� <1�mg�C/L�� 10�mg�C/L� �
Total�coliforms� <10�cfu/100mL�– <1�cfu/100mL�– �107 cfu/100mL� 200�cfu/100mL�
Fecal�coliforms� <1�106 cfu/100mL� <1�cfu/100mL�� 103 cfu/100mL�14�for�any�sample,���
0�for�90%�Helminth�eggs� <1/L��10/L� <0.1/L�� 5/L� �
Viruses� <1/L�� 100/L� <1/50L� �Heavy�metals� � <0.001�mg�Hg/L �
<0.01�mg�Cd/L<0.1�mg�Ni/L��0.02�mg�Ni/L�
Inorganic� � >450�mg�TDS/L� �
Chlorine�residual� � 0.5�mg�Cl/L�� >1�mg�Cl/L� 1�mg/L�
Nitrogen� 10�mg�N/L�� 30�mg�N/L� <1�mg�N�� 30mgN/L� �Phosphorus� 0.1�mg�P/L�� 30�mg�P/L� <1�mg�P/L�� 20�mg�P/L� �
pH� � � 6�– 9�
Potential Constituents of Concern for Water Reuse
• Trace Organic Compounds (TOrCs)– Endocrine Disrupting Chemicals (EDCs)– Pharmaceuticals and Personal Care Products
(PPCPs)
• Pathogenic Microorganisms
Endocrine Disrupting Chemicals
• Endocrine Disruptor – an exogenous substance or mixture that alters functions of the endocrine (hormone) system and consequently causes adverse health effects.
• Dose Response Relationship– EDCs mimic or antagonize natural hormones– Low-dose effects – controversial– Timing of exposure is critical
Pharmaceuticalsand Personal Care Products (PPCP’s)
• PPCPs include:– Prescription and over-the counter therapeutic drugs – Veterinary drugs – Fragrances – Cosmetics – Sun-screen products – Diagnostic agents – Vitamins
• Sources of PPCPs:– Human activity – Residues from pharmaceutical manufacturing (well defined and controlled) – Residues from hospitals – Illicit drugs – Veterinary drug use, especially antibiotics and steroids – Agribusiness
Concerns with EDC’s and PPCP’s• Lack of research on health risks:
– Ingestion of reclaimed water insignificant– Constituents generally in �g/L or ng/L range– Many chemical constituents have short half-lives in the
environment and are biodegradable– Concentrations of these constituents able to cause adverse
health effects are extremely unlikely
• Little information on whether PPCPs and EDCs become concentrated on vegetation or in soil– Studies indicate large organic molecules don’t enter edible
portions of plants
• There is no evidence to show that EDCs and PPCPs present a health risk from non-potable reclaimed water applications
Target CompoundsPharmaceuticals (20) Potential EDCs (26) Steroid Hormones (5) Phytoestrogens (11)
Atenolol Atrazine Estradiol ApigeninAtorvastatin Benzophenone Estrone Biochanin Ao-Hydroxy atorvastatin BHA Ethinylestradiol Chrysinp-Hydroxy atorvastatin BHT Progesterone CoumestrolCarbamazepine �-BHC Testosterone DaidzeinDiazepam �-BHC EquolDiclofenac �-BHC FormononetinDilantin �-BHC GenisteinEnalapril Bisphenol A GlyciteinFluoxetine Butylbenzyl phthalate MatairesinolNorfluoxetine DEET NaringeninGemfibrozil DiazinonMeprobamate Dioctyl phthalateNaproxen GalaxolideRisperidone LinuronSimvastatin MethoxychlorSimvastatin hydroxy acid MetolachlorSulfamethoxazole Musk ketoneTriclosan NonylphenolTrimethoprim Octachlorostyrene
OctylphenolTCEPTCPPTonalideTraseolideVinclozolin
62 Compounds
Pharmaceuticals Potential EDCs Steroid Hormones Phytoestrogens
Detected in Raw Surface Water
Atenolol Atrazine Estradiol ApigeninAtorvastatin Benzophenone Estrone Biochanin Ao-Hydroxy atorvastatin BHA Ethinylestradiol Chrysinp-Hydroxy atorvastatin BHT Progesterone CoumestrolCarbamazepine �-BHC Testosterone DaidzeinDiazepam �-BHC EquolDiclofenac �-BHC FormononetinDilantin �-BHC GenisteinEnalapril Bisphenol A GlyciteinFluoxetine Butylbenzyl phthalate MatairesinolNorfluoxetine DEET NaringeninGemfibrozil DiazinonMeprobamate Dioctyl phthalateNaproxen GalaxolideRisperidone LinuronSimvastatin MethoxychlorSimvastatin hydroxy acid MetolachlorSulfamethoxazole Musk ketoneTriclosan NonylphenolTrimethoprim Octachlorostyrene
OctylphenolTCEPTCPPTonalideTraseolideVinclozolin
EstradiolAtorvastatin Benzophenone Biochanin Ao-Hydroxy atorvastatin BHA Ethinylestradiol Chrysinp-Hydroxy atorvastatin BHT Coumestrol
�-BHC Testosterone DaidzeinDiazepam �-BHC Equol
�-BHC�-BHC
Enalapril Bisphenol A GlyciteinFluoxetine Butylbenzyl phthalate MatairesinolNorfluoxetine Naringenin
Diazinon
RisperidoneSimvastatin MethoxychlorSimvastatin hydroxy acid
Musk ketone
OctachlorostyreneOctylphenol
TonalideTraseolideVinclozolin
(in at least 20% of samples)24 of 62 Compounds
Atenolol Atrazine Estradiol ApigeninAtorvastatin Benzophenone Estrone Biochanin Ao-Hydroxy atorvastatin BHA Ethinylestradiol Chrysinp-Hydroxy atorvastatin BHT Progesterone CoumestrolCarbamazepine �-BHC Testosterone DaidzeinDiazepam �-BHC EquolDiclofenac �-BHC FormononetinDilantin �-BHC GenisteinEnalapril Bisphenol A GlyciteinFluoxetine Butylbenzyl phthalate MatairesinolNorfluoxetine DEET NaringeninGemfibrozil DiazinonMeprobamate Dioctyl phthalateNaproxen GalaxolideRisperidone LinuronSimvastatin MethoxychlorSimvastatin hydroxy acid MetolachlorSulfamethoxazole Musk ketoneTriclosan NonylphenolTrimethoprim Octachlorostyrene
OctylphenolTCEPTCPPTonalideTraseolideVinclozolin
Estradiol ApigeninAtorvastatin Benzophenone Estrone Biochanin Ao-Hydroxy atorvastatin BHA Ethinylestradiol Chrysinp-Hydroxy atorvastatin BHT Progesterone Coumestrol
�-BHC Testosterone DaidzeinDiazepam �-BHC EquolDiclofenac �-BHC Formononetin
�-BHC GenisteinEnalapril Bisphenol A GlyciteinFluoxetine Butylbenzyl phthalate MatairesinolNorfluoxetine Naringenin
DiazinonDioctyl phthalate
Naproxen GalaxolideRisperidone LinuronSimvastatin MethoxychlorSimvastatin hydroxy acid
Musk ketoneTriclosan NonylphenolTrimethoprim Octachlorostyrene
Octylphenol
TonalideTraseolideVinclozolin
Detected in Finished Drinking WaterPharmaceuticals Potential EDCs Steroid Hormones Phytoestrogens
(in at least 20% of samples)11 of 62 Compounds
�1 cup coffee
(17 ng/L, 240 mL)
890 mL Secondary Wastewater
(4.6 ng/L)
Human Health RelevanceEEq Comparison
Microorganisms/Pathogens in Wastewater
Agent Disease
BacteriaSalmonellaShigella
ProtozoaGiardiaCryptosporidium
HelminthsAscaris lumbricoidesTaenia saginata
VirusesEnterovirusesHepatitis A
SalmonellosisShigellosis
GiardiasisCryptosporidiosis
AscariasisTaeniasis
Gastroenteritis, othersInfectious Hepatitis
Pathogen Destruction/ Removal/Inactivation
• Conventional tertiary treatment (including disinfection):– Effectively eliminates bacteria and helminthes– Viruses reduced to low or immeasurable levels– Giardia and Cryptosporidium may remain
• Membranes:– Effectively removes all parasites– Reverse osmosis can reduce most pathogens– Membrane filtration can remove 0-2 logs of viruses
• Ultraviolet light: – Effectively inactivates Giardia, Cryptosporidium, bacteria, and
most viruses
Public health and microbial water quality in distribution systems
• Distribution systems are not sterile
• Heterotrophic plate count bacteria (HPCs)
• Enteric pathogens
• Environmental pathogens indigenous to system
• Biofilms vs. bulk water
• Distribution systems are living ecosystems
Channah�Rock,�Ph.D.
Water�Quality�Extension�Specialist�and
Assistant�Professor
Department�of�Soil,�Water,�and
Environmental�Science
The�University�of�Arizona
Maricopa�Agricultural�Center
37860�W.�Smith�Enke Road
Maricopa,�AZ�85138
(520)381�2258
