Water Reuse in AZ: Channah Rock. Overview. How can reclaimed water be used? Identify benefits & concerns of water recycling

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1 Water Reuse in AZ: Challenges and Opportunities Channah Rock Assistant Water Quality Specialist University of Arizona Dept. of Soil, Water, and Environmental Science Overview What is reclaimed water? How can reclaimed water be used? Identify benefits & concerns of water recycling Discuss additional water sources for reuse

2 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 Projected 25% additional increase by 2015 Increased Water Demand Residential Commercial Agricultural

3 Uses of Water Municipal Human consumption (primary) Landscape irrigation Fire protection Agricultural Irrigation Livestock Human consumption (secondary) Industrial Factories/Refineries Power Plants Environmental River habitat maintenance Human consumption (secondary) The Great Water Balancing Act Industrial Environmental Available Water Agricultural Municipal

4 How much water do you use? Of the total quantity of drinking water supplied to residential homes in Arizona 65 greater then % of a residence's total water consumption is for outdoor water use. What are viable options for extending the water supply?

5 Reclaimed water is treated wastewater that can be used for irrigation and other non-potable uses to extend our water supplies. Reclaimed Water 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.

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7 Reuse Options Urban Industrial Agriculture Environmental and Recreational Groundwater Recharge Augmentation of Potable Supplies

8 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

9 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

10 Arizona Reclaimed Water Classifications Water Quality Class Class A+ Class A Requirements 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. 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+ Class B Class C 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. a. The concentration of fecal coliform organisms is less than 200 CFU/100 ml. b. Includes requirements for nitrogen management and lining of impoundments. 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.

11 1. Screens remove plastics, and other nonbiodegradables while sand and grit settles 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 3. Aerobic treatment uses dissolved oxygen to promote the growth of biological floc that substantially removes organic material FILTRATION 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 6. Filtration uses filters to finish the water by removing small particles Reclaimed Water Permits Class A+ Class A Class B+ Class B Class C Michele Robertson, ADEQ

12 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 Arizona Water Reuse Central Arizona Project water Ground water Water treatment Community GRAY WATER reuse BIOSOLIDS: land application Wastewater treatment: primary + secondary CROP IRRIGATION EFFLUENT DISCHARGED to dry river bed Further treatment RECLAIMED WATER for landscape irrigation

13 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 soilaquifer 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

14 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

15 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 10 7 cfu/100ml 200 cfu/100ml Fecal coliforms < cfu/100ml <1 cfu/100ml 10 3 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

16 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 Pharmaceuticals and 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

17 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 Compounds Pharmaceuticals (20) Potential EDCs (26) Steroid Hormones (5) Phytoestrogens (11) Atenolol Atrazine Estradiol Apigenin Atorvastatin Benzophenone Estrone Biochanin A o-hydroxy atorvastatin BHA Ethinylestradiol Chrysin p-hydroxy atorvastatin BHT Progesterone Coumestrol Carbamazepine -BHC Testosterone Daidzein Diazepam -BHC Equol Diclofenac -BHC Formononetin Dilantin -BHC Genistein Enalapril Bisphenol A Glycitein Fluoxetine Butylbenzyl phthalate Matairesinol Norfluoxetine DEET Naringenin Gemfibrozil Diazinon Meprobamate Dioctyl phthalate Naproxen Galaxolide Risperidone Linuron Simvastatin Methoxychlor Simvastatin hydroxy acid Metolachlor Sulfamethoxazole Musk ketone 62 Compounds Triclosan Trimethoprim Nonylphenol Octachlorostyrene Octylphenol TCEP TCPP Tonalide Traseolide Vinclozolin

18 Detected in Raw Surface Water Pharmaceuticals Potential EDCs Steroid Hormones Phytoestrogens Atenolol Atrazine Estradiol Apigenin Atorvastatin Benzophenone Estrone Biochanin A o-hydroxy atorvastatin BHA Ethinylestradiol Chrysin p-hydroxy atorvastatin BHT Progesterone Coumestrol Carbamazepine -BHC Testosterone Daidzein Diazepam -BHC Equol Diclofenac -BHC Formononetin Dilantin -BHC Genistein Enalapril Bisphenol A Glycitein Fluoxetine Butylbenzyl phthalate Matairesinol Norfluoxetine DEET Naringenin Gemfibrozil Diazinon Meprobamate Dioctyl phthalate Naproxen Galaxolide Risperidone Linuron Simvastatin Methoxychlor Simvastatin hydroxy acid Metolachlor Sulfamethoxazole Musk ketone Triclosan Nonylphenol Trimethoprim Octachlorostyrene Octylphenol TCEP TCPP Tonalide Traseolide Vinclozolin 24 of 62 Compounds (in at least 20% of samples) Detected in Finished Drinking Water Pharmaceuticals Potential EDCs Steroid Hormones Phytoestrogens Atenolol Atrazine Estradiol Apigenin Atorvastatin Benzophenone Estrone Biochanin A o-hydroxy atorvastatin BHA Ethinylestradiol Chrysin p-hydroxy atorvastatin BHT Progesterone Coumestrol Carbamazepine -BHC Testosterone Daidzein Diazepam -BHC Equol Diclofenac -BHC Formononetin Dilantin -BHC Genistein Enalapril Bisphenol A Glycitein Fluoxetine Butylbenzyl phthalate Matairesinol Norfluoxetine DEET Naringenin Gemfibrozil Diazinon Meprobamate Dioctyl phthalate Naproxen Galaxolide Risperidone Linuron Simvastatin Methoxychlor Simvastatin hydroxy acid Metolachlor Sulfamethoxazole Musk ketone Triclosan Nonylphenol Trimethoprim Octachlorostyrene Octylphenol TCEP TCPP Tonalide Traseolide Vinclozolin 11 of 62 Compounds (in at least 20% of samples)

19 Human Health Relevance EEq Comparison 1 cup coffee (17 ng/l, 240 ml) 890 ml Secondary Wastewater (4.6 ng/l) Microorganisms/Pathogens in Wastewater Agent Bacteria Salmonella Shigella Protozoa Giardia Cryptosporidium Helminths Ascaris lumbricoides Taenia saginata Viruses Enteroviruses Hepatitis A Disease Salmonellosis Shigellosis Giardiasis Cryptosporidiosis Ascariasis Taeniasis Gastroenteritis, others Infectious Hepatitis

20 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

21 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 W. Smith Enke Road Maricopa, AZ (520)