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WRF Webcast 4537
Improving Water Quality and Consumer
Satisfaction Based on the SMCLs
August 21, 2014
2
USEPA SECONDARY MAXIMUM CONTAMINANT LIMITS: A STRATEGY FOR DRINKING WATER AESTHETIC QUALITY AND
CONSUMER ACCEPTABILITY
Principal Investigator: Andrea Dietrich, PhD
August 21, 2014 Funded by Philadelphia Water Department Water Research Foundation Project #4537
3
Why This Project? • Secondary Maximum Contaminant Levels
recognized as important parameters impacting customer perception of drinking water quality
• Variable state regulations
• Philadelphia Water Department and Andrea Dietrich supported a summary document.
• WRF supports their efforts through the Facilitated Research Program
4
Taste and Odor Control – 48 projects • A Decision Tool for Earthy/Musty Taste and Odor Control (WRF Project
#3032, 9/13)
Manganese – 21 projects • Guidance for the Treatment of Manganese (WRF Project #4373)
SMCLs as a Research Topic
5
MANGANESE AS A RESEARCH TOPIC
Aluminum Chloride Color Copper
Corrosivity Fluoride
Foaming agents Iron Manganese
Odor pH Silver Sulfate
TDS Zinc
Andrea M. Dietrich, Ph.D. Professor, Civil and Environmental Engineering Adjunct Professor, Food Science and Technology
Improving Water Quality and Consumer Satisfaction using Guidance from the SMCLss
Presentation copyright A.M. Dietrich 2014
• Professor, Civil & Environmental
Engineering, Virginia Tech
• Adjunct Professor, Food Science &
Technology
• Co-director, VT‟s Water INTERface
Interdisciplinary Graduate Education
Program
• Chair, International Water
Association‟s Specialist Group on
Off-Flavours in the Aquatic
Environment
• Past chair, American Water Works
Association Taste and Odor
Committee
• Author of over 100 peer-reviewed
journal articles and book chapters
• Author of technical reports for the
Water Research Foundation,
AWWA, utilities, consultants,
industry, and government
• Instructor for Introduction to
Environmental Engineering,
Environmental Chemistry, Water for
Health, and Techniques for
Environmental Analysis
• Research areas water quality;
sensory analysis of environmental
contaminants, odorants, and
tastants; water treatment; potable
water infrastructure; fate and
transport of organic and inorganic
chemicals.
7
Dr. Andrea M. Dietrich - Brief Bio [email protected]
• When promulgating the SMCLs, the USEPA (1979)
stated: “The absence of taste and odor in water
helps to maintain the consumer’s confidence in
the quality of their drinking water …”
• Consumer judge tap water by taste, odor, color,
and appearance
• SMCLs are primary concern of consumers
• Since SMCLs generally treated as guidelines,
receive less attention than PMCLs
Environmental and Water Resources
Civil and Environmental Engineering
Motivation
8
• Consumers
• Water treatment
• Sensory science
• Bottled water
• Source water quality
• Salinity, Algal T&O episodes, chemical spills
• SMCLs need to evolve!
9
Environmental and Water Resources
Civil and Environmental Engineering
Most SMCLs are 35-50 years old!
Since inception, these have evolved:
Environmental and Water Resources
Civil and Environmental Engineering
• Water that is • Clear
• Colorless
• Relatively odorless
• Tasty
• Not CHANGING- • CONSISTENCY!!!!
Photo credit: AM Dietrich
What instills consumer confidence?
10
• Aesthetic - taste, odor, color, foaming
• e.g., TDS, chloride, sulfate
• Cosmetic - human appearance
• fluoride and silver
• Technical - corrosion, staining, scaling, sediment
• e.g., corrosivity, pH, iron
Environmental and Water Resources
Civil and Environmental Engineering
USEPA SMCLs Categories
11
Outline: 15 SMCLs
• Total dissolved solids (TDS)
• Major anions and cations
• Cl-, SO4=
• Minor anions and cations
• Cu, Fe, Mn, Al, Zn, Ag, F
• Odor
• Other Aggregate parameters
• pH, corrosivity, color, foaming agents Environmental and Water Resources
Civil and Environmental Engineering 12
Total dissolved solids (TDS)
Cl-
• Aggregate
measure of
anions & cations
• Salinity
• Overall indicator
of water quality
SMCL = 500 mg/L TDS
• Aesthetic and Technical
• Sources: rocks and minerals
• TDS gives water good taste
• Variable consumer liking
• SMCL consistent with current
science
• Importance of TDS increasing
as source water TDS
increases
14
Environmental and Water Resources
Civil and Environmental Engineering
Photo credit: AM Dietrich
Context for TDS SMCL
Water Type TDS, mg/L
Human Drinking Water
USEPA SMCL Accepted globally
< 500
< 1,500
Freshwater 0 to ~ 5,000
Brackish Water 5,000 - 30,000
Saline water 30,000 - 50,000
Brine <50,000
15
Environmental and Water Resources
Civil and Environmental Engineering
16
TDS in Ground Water on the RISE
Environmental and Water Resources
Civil and Environmental Engineering
USGS: Methods for Evaluating
Groundwater Quality Data in the
United States, 1988–2010
Severe drought increases TDS in
drinking water
17 Environmental and Water Resources
Civil and Environmental Engineering
Cl-
Desalination
Environmental and Water Resources
Civil and Environmental Engineering
Corrosive!
No
Nutrition!
18
When can consumers detect
changes in TDS?
• Increase TDS from low TDS water more readily
detected than decrease TDS from high TDS water
• Room temperature > > chilled water
• Types of ions important
• Chloride > Sulfate
• Sodium > Calcium
19
20
Environmental and Water Resources
Civil and Environmental Engineering
Mineral Typical
Concentration, mg/L Hard Water Soft Water
Ca2+ 50 11
Na+ 15 6
Mg2+ 10 1.5
Cl- 24 10
HCO3- 125 25
SO4= 115 20
TDS 100-400 25-100
SMCL
SMCL
Consider
SMCLs
Major cations and anions
contributing to TDS
Anion - Cation charge balance
SMCL = 250 mg/L Chloride
• Aesthetic- salty taste; Technical- corrosion
• Sources: natural and anthrophogenic
• In 1979, lower value considered by USEPA
• In 21st century, increasing TDS in source waters
• Consumers do not prefer chloride
• Consider lower SMCL for taste & corrosion
21
Environmental and Water Resources
Civil and Environmental Engineering www.columbus.gov
Sodium – consider SMCL • Aesthetic – salty taste
• Sources: natural and anthropogenic
• 1980s- established Na+ as cause of “salty” (not Cl-)
• Anion affects taste: Cl- >SO42-
• USEPA Advisory 30 - 60 mg Na/L for taste
• Consider establishing SMCL
22
Environmental and Water Resources
Civil and Environmental Engineering www.columbus.gov
SMCL = 250 mg/L Sulfate
• Aesthetic- salty taste
• Sources: natural, anthropogenic
• Can be major contributor to TDS
• Sulfate is a laxative; health advisory 500 mg/L
• SMCL consistent with current science
23
Environmental and Water Resources
Civil and Environmental Engineering
SO42-
Hardness - Consider SMCL
24
USGS Map
• Aesthetic: bitter taste of Ca and Mg
• Technical - scaling
• Sources
• Natural
• Desalination
• Remineralization
• Consider establishing SMCL
Environmental and Water Resources
Civil and Environmental Engineering
Select TDS References (reverse chronology)
• Dietrich AM. 2014. USEPA SMCLs: A Strategy for Drinking Water Quality and Consumer
Acceptability. Denver, CO.Water Research Foundation. 56 pp.
• García V, Fernández A, Medina ME, Ferrer O, Cortina JL, Valero F, Devesa R. 2014. Flavour
assessment of blends between desalinated and conventionally treated sources. Desalination and
Water Treatment DOI:10.1080/19443994.2013.875943.
• Dietrich AM, Gallagher CD. 2013. Consumer ability to detect the taste of total dissolved solids. J.
American Water Works Association 105(5):E255-263.
• Platikanov S, Garcia V, Fonseca I, Rullán E, Devesa R, Tauler R. 2013. Influence of minerals on the
taste of bottled and tap water: A chemometric approach. Water Research 47:693-704.
• Lindsey BD, Ruppert MG. 2012. Methods for Evaluating Temporal Groundwater Quality Data and
Results of Decadal-Scale Changes in Chloride, Dissolved Solids, and Nitrate Concentrations in
Groundwater in the United States, 1988–2010. Reston VA:United States Geological Survey, 47..
• Devesa R, García V, Matía L. 2010. Water flavor improvement by membrane (RO and EDR)
treatment. Desalination 250(1):113-117. Devesa R, García V, Matía L. 2010. Water flavor
improvement by membrane (RO and EDR) treatment. Desalination 250(1):113-117.
• Gallagher CD, Dietrich AM. 2010. TDS and temperature affect consumer taste preferences. OpFlow
36(11):20-22.
• Deb A, McCammon SB, Snyder J, Dietrich AM. 2010. Impacts of Lining Material on Water Quality
[Project #4036] Denver, CO.Water Research Foundation. 181 pp.
• Burlingame GA, Dietrich AM, Whelton AJ. 2007. Understanding the taste of tap water. J. American
Water Works Association 99(5):100-111.
• Biggs J, Thomure T, Arnol K, Cotton C. 2007. Public outreach tool used in determining customer
preferences of water aesthetics. In: Proceedings of the AWWA Water Quality Technology
Conference. Charlotte, North Carolina, November 4-8, 2007.
25
Select TDS References (reverse chronology) • Dietrich AM. 2006. Aesthetic issues for drinking water. Journal of Water and Health, 4 (supplement
1):11-16.
• USEPA (U.S. Environmental Protection Agency). 2003a. Drinking Water Advisory: Consumer
Acceptability Advice and Health Effects Analysis on Sodium.
www.epa.gov/safewater/ccl/pdf/sodium.pdf. EPA 822-R-03-006, Washington DC.
• Taste and Odor Committee of the American Water Works Association. 2002. Options for a Taste and
Odor Standard. J. American Water Works Association 94(6):80-87.
• Lawless HT, Rapaki F, Horne J, Hayes A.2003. The taste of calcium and magnesium salts and
anionic modifications. Food Quality and Preference 14:319-325.
• Matia L. 1995. Treatment of tastes in drinking water: Causes and control. In: Advances in Taste-and-
Odour Treatment and Control, Edited by I.H. Suffet Joel Mallevialle, Elizabeth Kawczynski Denver,
CO:American Water Works Association Research Foundation and Lyonnaise des Eaux.
• Bruvold WH, Daniels JI. 1990. Standards for mineral content in drinking water. J. American Water
Works Association, 82(2):59-65.
• Pangborn RM, Percore SD. 1982. Taste perception of sodium chloride in relation to dietary intake of
salt. American Journal of Clinical Nutrition 35(3):510-20.
• Murphy C, Cardello AV, Brand JG. 1981. Tastes of fifteen halide salts following water and NaCl:
Anion and cation effects. Physiology and Behavior 26(6):1083–1095.
• Zoeteman, BCJ, de Grunt FE, Köster EP, Smit KBJ, Punter PH. 1978. Taste assessment of
individual salts in water - methodology and preliminary findings by a selected national panel.
Chemical Senses 3(2):127-139.
• Pangborn RM, Bertolero L. 1972. Influence of temperature on taste intensity and degree of liking of
drinking water. J. American Water Works Association 64(8):511-515.
• Bruvold WH. 1968. Scales for rating the taste of water. J. Applied Psychology 52(3):245-253.
26
Environmental and Water Resources
Civil and Environmental Engineering
Audience participation
• In the past two years
(Aug 2012 - Aug
2014) how many
“salty” or “mineral”
taste episodes/events
occurred at your utility
that resulted in
consumer complaints?
27
• A. None
• B. Few (1-3)
• C. Several (4-6)
• D. Many, >7
• E. Do not know
Minor anions & cations
Consumers describing the taste of ferrous
Taste + Odor = Flavor
Flavor can be easily altered by changing the
odor associated with a taste
Iron and Copper Have FLAVOR- lipid
oxidation in the oral cavity produces volatile
odors
Same reaction as keys in your hand
Environmental and Water Resources
Civil and Environmental Engineering Photo credit: AM Dietrich 29
• Aesthetic – metallic flavor, color
• Technical – corrosion, blue-green staining
• Sources: copper pipe, brass
• 1.3 mg/L Cu = PMCL
• Population threshold 0.4 - 0.5 mg Cu/L
• Some do not taste >8 mg/L
• Soluble flavor; particulates little flavor
• Chemical monitoring to protect human health
• Consider lower SMCL for flavor - 0.4-0.5 mg/L
30
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = 1 mg/L Copper Photo credit: AM Dietrich
• Aesthetic – flavor of Ferrous Fe2+
• Technical – color/rust of Ferric Fe3+
• Sources: natural, iron pipe corrosion
• Population threshold 0.03 - 0.17 mg Fe2+/L
• Individual thresholds 0.007 to >14 mg Fe2+/L
• 0.3 mg/L Fe3+ readily visible in cup
• Reconsider SMCL as Fe causes detectable
metallic flavor at 1/10 the current SMCL
31
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = 0.3 mg/L Iron Photo credit: AM Dietrich
• Aesthetic = bitter, metallic taste
• Technical = black color, deposits
• Sources: natural
• Update SMCL as Mn(II) and Mn(IV) do not
cause metallic taste
• Reconsider SMCL as color/particles detectable
in cup at 0.005 mg/L MnO2
32
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = 0.05 mg/L Mn
Photo credit: AM Dietrich
SMCL = 0.05 to 0.2 mg/L
Aluminum
• Technical & Aesthetic
• Sources: alum, cement
• 0.05 mg/L = Treatment goal
• 0.2 mg/L avoids color
• Taste at > 4 mg/L
• SMCL consistent with current science
33
Environmental and Water Resources
Civil and Environmental Engineering
Photo credit: AM Dietrich
• Aesthetic – metallic, astringency
• Technical - corrosion
• Sources: galvanize pipe
• Astringent mouth feel at 5 mg/L Zn
• 5-30 mg/L Zn milky appearance or surface
scum when boiled
• SMCL consistent with current science
34
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = 5 mg/L Zinc
Photo credit: AM Dietrich
• Cosmetic – gray eyes, skin (argyria)
• Sources: disinfectant, nanosilver
• Increased use of nanosilver a concern
• SMCL consistent with current science
35
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = 0.1 mg/L Silver
Ag+ Ag+ Ag+
• Cosmetic- tooth discoloration and pitting
• Sources: natural and additive
• In 2011 USEPA and HHS recommended
0.7 mg/L F- added as guidance for
fluoridation
• Reconsider SMCL as new guidance
suggests range at ~0.7 mg/L F-
36
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = 2 mg/L Fluoride
F- F- F-
Select References, Cu, Fe, Mn (reverse chronology)
• Dietrich AM. 2014. USEPA SMCLs: A Strategy for Drinking Water Quality and Consumer
Acceptability. Denver, CO.Water Research Foundation. 56 pp.
• Sain A, Griffin A, Dietrich AM. 2014. Assessing taste and visual perception of Mn(II) and Mn(IV) in
Drinking Water. J. American Water Works Association 106(1):E32-34.
• Sain A, Dietrich AM. 2014. Rethinking aesthetic guidelines for manganese and iron in drinking water.
J. Water Supply: Res. Technol. – AQUA, accepted.
• Stanford BD, Wright B, Routt JC, Debroux JF, Khan, SJ. 2013. Water Quality Impacts of Extreme
Weather-related Events. Denver, CO: Water Research Foundation.
• Ömür-Özbek P, Dietrich AM, Duncan SE, Lee YW. 2012. Role of lipid oxidation, chelating agents,
and antioxidants in metallic flavor development in the oral cavity. J. Agricultural and Food Chemistry
60(9):2274-2280.
• Ömür-Özbek P. 2012. Global Taste and Odor Survey of Water Utilities: Final Report to the American
Water Works Association from the Taste and Odor Committee. Denver, CO: AWWA.
• Benson AS, Dietrich AM, Gallagher DL. 2012. Evaluation of iron corrosion release models for water
distribution systems; Critical Reviews in Environmental Science and Technology 42(1):44-97.
• Ömür-Özbek P, Dietrich AM. 2011. Retronasal perception and flavor thresholds of iron and copper in
drinking water. J. Water and Health 9(1):1-9.
• Ayotte JD, Gronberg JM, Apodaca LE. 2011. Trace Elements and Radon in Groundwater Across the
United States: U.S. Geological Survey Scientific Investigations Report 2011-5059: Reston, Virginia.
• Mirlohi S, Dietrich AM, Duncan SE. 2011. Age-associated variation in sensory perception of iron in
drinking water and the potential for overexposure in the human population. Environmental Science
and Technology 45(15):6575-83.
37
Environmental and Water Resources
Civil and Environmental Engineering
Select References Cu, Fe, Mn (reverse chronology)
• Hong J-H, Duncan SE, Dietrich AM, O‟Keefe S. 2010 Evaluation of the operationally defined soluble,
insoluble, and complexing copper consumed through drinking water in human saliva. European Food
Research and Technology 231:977-984.
• Hong J-H, Duncan SE, Dietrich AM. 2010. Effect of copper speciation at different pH on temporal
sensory attributes of copper. Food Quality and Preference 21(1):132-139.
• Dietrich AM. 2009. The sense of smell: contributions of orthonasal and retronasal perception applied
to metallic flavor of drinking water. J. Water Supply: Research Technology-AQUA 58(8):562-570.
• Dietrich AM, Cuppett JD, Duncan SE. 2008. How much copper is too much? OpFlow 34(9):8-30.
• Gallagher DL, Cuppett J. 2007. Evaluation of threshold limit methods for sensory data. Water
Science and Technology 55(5): 67-75.
• Epke EM, Lawless HT. 2007. Retronasal smell and detection thresholds of iron and copper salts.
Physiology and Behavior 92:487-491.
• Pizarro F, Araya M, Vásquez M, Lagos G, Olivares M, Méndez MA, Leyton B, Reyes A, Letelier V,
Uauy R. 2007. Biological Trace Element Research 116(2):131-45.
• Kohl PM, Medlar SJ. 2006. Occurrence of Manganese in Drinking Water and Manganese Control.
Denver CO:AWWA Research Foundation, 436 pp.
• Burlingame GA, Lytle DA, Snoeyink VL. 2006. Why red water? Understanding iron release in
distribution systems. Opflow, 32(12):12-16.
• Cerrato JM, Reyes LP, Alvarado, Dietrich AM. 2006. Effect of PVC and iron materials on Mn (II)
deposition in drinking water distribution systems. Water Research, 40(14):2720-2726, 2006.
• Cuppett JD, Duncan SE, Dietrich AM. 2006. Evaluation of copper speciation and water quality factors
that affect aqueous copper tasting sensitivity. Chemical Senses 31(7):689-697.
38
Environmental and Water Resources
Civil and Environmental Engineering
Select References Cu, Fe, Mn (reverse chronology)
• Dietrich AM. 2006. Aesthetic issues for drinking water. J. Water and Health, 4 (supplement 1):11-16.
• Booth S, Brazos B. 2005. Qualitative Procedures for Identifying Particulate Matter in Distribution and
Tap Waters, Awwa Research Foundation, Denver, CO. 164 pp.
• Koseki M, Fujiki S, Tanaka Y, Noguchi H, Nishikawa T. 2005. Effect of water hardness on the taste
of alkaline electrolyzed water. Journal of Food Science 70(4):S249-S253.
• Keast R. 2003. The effect of zinc on human taste perception. J. Food Sci., 68:1871-1877.
• Kirmeyer GJ, Friedman M, Martel K, Thompson G, Clement J, Frey M. 2002. Guidance Manual for
Maintaining Distribution System Water Quality. Denver, CO.Awwa Research Foundation and
American Water Works Association, 325 pp.
• Young W, Horth H, Crane R, Ogden T, Arnott M. 1996. Taste and odour threshold concentrations of
potential potable water contaminants. Water Research, 30(2):331-340.
• Hettinger TP, Myers WE, Frank ME. 1990. Role of olfaction in perception of non-traditional „taste‟
stimuli. Chemical Sense 16:755-760.
• Mallevialle J, Suffet IH (eds). 1987. Identification and Treatment of Tastes and Odors in Drinking
Water. Denver, CO:American Water Works Association, 387 pp.
• Griffin AE. 1960. Significance and removal of manganese in water supplies. J. American Water
Works Association 52(10):1326-1334.
• Cohen JM, Kamphake LJ, Harris EK, Woodward RL. 1960. Taste threshold concentrations of metals
in drinking water. J. American Water Works Association 52(5):660-670.
39 Environmental and Water Resources
Civil and Environmental Engineering
“Water companies are teaching their
workers, and even their consumers, to
identify and report funny tastes and
odors. Sensory analysis (using taste
buds and noses) can find all sorts of
water problems – sometimes faster than
lab tests- and even save lives.”
Odor
• Aesthetic - odor
• Sources: MANY
• Reconsider TON method
• Dilution method; time consuming
• Does not correlate with consumer complaints
• Possible replacements
• Flavor Profile Analysis (FPA) (Standard Method 2170)
• Total Intensity of Odor Method
41
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = TON < 3
• Reconsider odor SMCL to provide specific
guidance for select odorants
• Base on consumer feedback or sensory analysis
• California: 0.005 mg MTBE/L standard
• 10 ng/L guidance for geosmin and 2-methylisoborneol
• Philadelphia, PA
• Australia
• Japan
• Metropolitan WDSC
• Monitor with either chemical or sensory methods
42
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = TON < 3
Geosmin 2-Methylisoborneol
• Reconsider odor SMCL to implement method to
assess new materials uses in distribution and
premise plumbing
• Migration of odors from new materials
• Migration methods exist
• Food and Beverage packaging
43
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = TON < 3
Photo credit: AM Dietrich
Audience participation
• In the past two years
(Aug 2012 - Aug 2014)
how many ODOR
episodes/events
occurred at your utility
that resulted in
consumer complaints?
44
• A. None
• B. Few (1-3)
• C. Several (4-6)
• D. Many, >7
• E. Do not know
Select References for Monitoring Odors (reverse chronology)
• Dietrich AM. 2014. USEPA SMCLs: A Strategy for Drinking Water Quality and Consumer
Acceptability. Denver, CO.Water Research Foundation. 56 pp.
• Ömür-Özbek P. 2012. Global Taste and Odor Survey of Water Utilities: Final Report to the American
Water Works Association from the Taste and Odor Committee. Denver, CO: AWWA.
• APHA (American Public Health Association), American Water Works Association (AWWA), Water
Environment Federation (WEF). 2012. Standard Methods for the Examination of Water and
Wastewater, 22nd ed. (Rice EW, Baird RB, Eaton AD, Clesceri LS. eds.) Washington DC.
• Dale MS, Desrochers RD, Labernik SM. Moylan MS. 2011. Threshold Odor Number versus Flavor
Profile Analysis: a case study in the endeavor to measure consumer acceptance. Presented at the 9th
IWA Symposium on Off-Flavours in the Aquatic Environment, Aberdeen, Scotland, August 2011.
• Desrochers R. 2008. Sensory analysis in the water industry. Journal of the American Water Works
Association 100(10):50-54.
• Durand ML, Dietrich AM. 2007. Contributions of silane cross-linked PEX pipe to chemical/solvent
odors in drinking water. Water Science and Technology 55(5):153-160.
• Gallagher DL, Cuppett J. 2007. Evaluation of threshold limit methods for sensory data. Water Science
and Technology 55(5): 67-75.
• Heim T, Dietrich AM. 2007. Sensory aspects and water quality impacts of chlorinated and
chloraminated drinking water in contact with HDPE and cPVC pipe, Water Research 41:757-764.
• Tomboulian P, Schweitzer L, Mullin K, Wilson J, Khiari D. 2004. Materials used in drinking water
distribution systems: contribution to taste-and-odor. Water Science and Technology, 49(9):219-226.
• Hrudey SE, Hrudey EJ. 2004. Safe Drinking Water Lessons from Recent Outbreaks in Affluent
Nations. London, England: IWA Publishing.
• Dietrich AM, Whelton A, Hoehn R, Anderson R, Wille M. 2004. Attribute rating test for sensory
analysis. Water Science and Technology 49(9):61-67.
45
Environmental and Water Resources
Civil and Environmental Engineering
Select References for Monitoring Odors (reverse chronology)
• Dietrich AM, Hoehn RC, Burlingame GA, Gittelman T. 2004. Practical Taste-and-Odor Methods for
Routine Operations: DECISION TREE. Denver, CO; Awwa Research Foundation, 161pp.
• Schweitzer L, Tomboulian P, Atasi K, Chen T, Khiari D. 2004. Utility quick test for analyzing materials
for drinking water distribution systems for effect on taste and odor. Water Science and Technology
49(9):75-80.
• Marchesan M, Morran J. 2004. Tastes associated with products in contact with drinking water. Water
Science and Technology 49(9):227-231.
• Skjevrak I, Due A, Gjerstad KO, Herikstad H. 2003. Volatile organic components migrating from
plastic pipes (HDPE,PEX and PVC) into drinking water. Water Research 37:1912-1920.
• Dietrich AM, Burlingame GA, Hoehn RC. 2003. Strategies for taste-and-odor testing methods, OpFlow
29(10)10-14; (reprinted in Volume XXVIII, No. 2 (March - April 2004) of the Arab Water World (AWW).
• Khiari D, Barrett S, Chinn R, Bruchet A, Piriou P, Matia L, Ventura F, Suffet IH, Gittelman T,
Leutweiler P. 2002. Distribution Generated Taste-and-Odor Phenomena. Denver,CO:AwwaRF, 340 p.
• Graham M, Najm I, Simpson M, MacLeod B, Summers S, Cummings L. 2000. Optimization of
powdered activated carbon application for geosmin and MIB removal. Denver, CO: AWWA Research
Foundation, 136 pp.
• Rigal S, Danjou J. 1999. Tastes and odors in drinking water distribution systems related to the use of
synthetic materials. Water Science and Technology 40(6):203-208.
• Burlingame GA, Dann RM, Brock GL. 1986. A case study of geosmin in Philadelphia's water. J.
American Water Works Association 78:56-61.
• Mallevialle J, Suffet IH (eds). 1987. Identification and Treatment of Tastes and Odors in Drinking
Water. Denver, CO:American Water Works Association, 387 pp.
• Krasner SW, McGuire MJ, Ferguson VB. 1985. Tastes and odors: the flavor profile method. J.
American Water Works Association 77(3):34-39.
46
Environmental and Water Resources
Civil and Environmental Engineering
Other Aggregate SMCLs
pH
corrosivity
color
foaming agents
• Aesthetic
• < 6.5 bitter, metallic
• >8.5 slippery feel, soda taste
• Technical - corrosion
• Sources: natural, anthropogenic
• SMCL consistent with current science for taste
• Reconsider SMCL - corrosion control at basic pH
48
Environmental and Water Resources
Civil and Environmental Engineering
H+
OH-
SMCL = pH 6.5 - 8.5
• Aesthetic – metallic taste
• Technical – corrosion, corroded pipes/ fixtures
staining
• Reconsider SMCL as no method to directly
measure corrosivity
• SMCLs for chloride, copper, iron, manganese,
pH, total dissolved solids, and zinc can mitigate
aesthetic-related corrosion of metallic materials
49
Environmental and Water Resources
Civil and Environmental Engineering
Corrosivity SMCL = Non corrosive
• Aesthetic – visible tint, color
• Sources: NOM, Cu, Fe, Mn, dyes, industry
• 15 Color Units set where consumers begin to see
• SMCL for true color consistent with current
science
50
Environmental and Water Resources
Civil and Environmental Engineering
SMCL = 15 Color Units
Photo credit: AM Dietrich
• Aesthetic- taste, odor, color
• Sources: before about 1970,
non-biodegradable
surfactants
• Current standard consistent
with science but is it
needed?
51
Environmental and Water Resources
Civil and Environmental Engineering
SMCL=0.5 mg/L Foaming Agents
Photo credit: AM Dietrich
Ammonia – Consider SMCL
• Aesthetic – pungent taste and odor
• Sources: natural, chloramines
• T&O data confusing: older, speciation not clear
• Consider establishing SMCL
• Consider guidance from nitrification
52
Environmental and Water Resources
Civil and Environmental Engineering
NH4+ <=> NH3 + H+
Harnessing Consumer Feedback To Improve Water Quality
When promulgating the SMCLs, the
USEPA (1979) stated: “The absence of
taste and odor in water helps to maintain
the consumer’s confidence in the
quality of their drinking water …”
• Consumer judge their tap water by its taste,
odor, color, and appearance
• SMCL parameters are primary concern of
consumers
• Consumer feedback is a useful data stream
that drinking water providers should harness
for water quality
• The water industry should systematically
investigate number and types of water quality
descriptors from consumers
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Consumers
Consumers WTP personnel 55
Challenging for consumers to
describe odors
Dietrich, Phetxumphou, Gallagher. 2014
• COMMUNICATION
• Consumers need reassurance when water
provider is aware of water quality change
• Consumer and staff training for taste, odor, and
color identification
• Information and educational materials
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Consumers
Select References for Consumer Complaints Issues (reverse chronology)
• Dietrich AM, Phetxumphou K, Gallagher DL. 2014. Systematic tracking, visualizing, and interpreting of
consumer feedback for drinking water quality. Water Research accepted August 2014.
• Gallagher DL, Dietrich AM. 2014. Statistical approaches for analyzing customer complaint data to
assess aesthetic episodes in drinking water. J. Water Supply: Research and Technology-AQUA,
63(5):358-367.
• Philadelphia Water Department and CH2M HILL. 2013. Philadelphia Water Department
Contamination Warning System Demonstration Pilot Project: Customer Complaints Surveillance
Guidance. White paper submitted to USEPA as part of the Water Security Initiative grant Awarded to
Philadelphia Water Department. Downloadable from www.ch2mhill.com/iws. accessed October 2013.
• Doria M. 2010. Factors influencing public perception of drinking water quality. Water Policy 12:1-19.
• Speight V, Grayman W, Khanal N. 2010 Syngeries between security research and distribution system
water quality management. J. American Water Works Association 102(2):30-33.
• USEPA (U.S. Environmental Protection Agency). 2008. Water Security Initiative: Interim Guidance on
Developing an Operational Strategy for Contamination Warning Systems, EPA-817-R-08-002.
• Jones A, Dewey C, Doré K, Majowicz S, McEwen S, Waltner-Toews D, Henson S, Mathews E. 2007.
A qualitative exploration of the public perception of municipal drinking water. Water Policy 9(4):425.
• Hrudey SE, Hrudey EJ. 2007. A nose for trouble: the role of off-flavors in assuring safe drinking water.
Water Science and Technology 55(5):69-75.
• Lauer, WC. 2004. Water Quality Complaint Investigator's Field Guide. Denver CO: American Water
Works Association. 105 pp.
• Hrudey SE, Hrudey EJ. 2004. Safe Drinking Water Lessons from Recent Outbreaks in Affluent
Nations. London, England: IWA Publishing
• Taste and Odor Committee of the American Water Works Association. 2002. Options for a Taste and
Odor Standard. J. American Water Works Association 94(6):80-87.
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58
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• Keep consumer satisfaction at the forefront
• Understand SMCL-related issues in your system
• Collect and interpret consumer feedback as an
indicator of water quality
• Develop education materials for sensory issues
• Develop guidance for specific odorants
• Work with regulatory community to change TON
• Work together to develop an industry-wide data
base for gathering data related to the aesthetic,
cosmetic, and technical SMCLs
Recommendations for utilities and
water community
More Information
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Dietrich AM. 2014.
USEPA SECONDARY MAXIMUM
CONTAMINANT LIMITS:
A STRATEGY FOR DRINKING WATER
AESTHETIC QUALITY AND CONSUMER
ACCEPTABILITY.
Denver, CO. Water Research Foundation.
Acknowledgments
• WRF, especially Kim Linton and Michelle Suazo
for organizing webcast
• Gary Burlingame, Philadelphia Water
Department
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Civil and Environmental Engineering 60
QUESTIONS????
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