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City of Houston Public Works - Houston, TX

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Serves 2,700,000 people - Test data available: 2004-2007

This drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group (EWG) by the Texas Commission on Environmental Quality . It is part of EWG's national database that includes 47,667 drinking water utilities and 20 million test results. Water utilities nationwide detected more than 300 pollutants between 2004 and 2009. More than half of these chemicals are unregulated, legal in any amount. Despite this widespread contamination, the federal government invests few resources to protecting rivers, reservoirs, and groundwater from pollution in the first place. The information below summarizes test results for this utility and lists potential health concerns.

	This Drinking Water System	National Average
Exceed Health GuidelinesTests showing chemicals at concentrations above health guidelines established by federal and state health agencies. These guidelines are typically set at a levels that pose no significant health risk.	18 chemicals	4
Health Standard ExceedencesChemicals detected at concentrations above the legal limit, the Maximum Contaminant Level (MCLs) established by the U.S. EPA. Most MCLs are based on annual averages, so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.	3 chemicals	0.5
Pollutants FoundThe total number of contaminants detected since 2004, according to data provided by the state water agency.	46 chemicals	8
Tests ConductedThe total number of number of water quality tests conducted by water utilities and recorded in data provided by the state water agency.	22,083 tests	420

Contaminants Exceeding Health Guidelines

Contaminant	Average/ Maximum Result	Health Limit Exceeded	Legal Limit Exceeded	Testing History -Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
Alpha particle activityAlpha particles are a form of radiation released from mining waste pollutants and natural sources.	9.17 pCi/L 21.7 pCi/L	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L	Yes 15 pCi/L
Total haloacetic acids (HAAs)Total haloacetic acids refers to the sum of the concentrations of five related disinfection byproducts in a water sample: dichloroacetic acid, trichloroacetic acid, monochloroacetic acid, monobromoacetic acid and dibromoacetic acid.	22.22 ppb 70.9 ppb	Yes 0.7 ppb	Yes 60 ppb
Gross beta particle activity (pCi/L)Beta particles are a form of radiation frequently associated with nuclear testing and radioactive mineral deposits.	6.55 pCi/L 16.2 pCi/L	Yes	Yes 15 pCi/L
DibromochloromethaneDibromochloromethane is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	1.48 ppb 5.85 ppb	Yes 0.4 ppb	No 80 ppb
BromodichloromethaneBromodichloromethane is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	4.41 ppb 13.6 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 80 ppb
Total trihalomethanes (TTHMs)Total trihalomethanes constitute the sum of four disinfection byproducts: chloroform, bromodichloromethane, dibromochloromethane, and bromoform.	20.11 ppb 69.3 ppb	Yes 9.8 ppb	No 80 ppb
ChloroformChloroform is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	11.29 ppb 36.58 ppb	Yes 5.7 ppb	No 80 ppb
Dichloroacetic acidDichloroacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	14.82 ppb 45 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 60 ppb
BromoformBromoform is a disinfection byproduct from the trihalomethane (THM) family, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	0.34 ppb 2.4 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 80 ppb
Arsenic (total)Arsenic contaminates drinking water due to mining runoff, erosion of natural deposits, emissions from glass and electronics processing and the use of arsenical compounds as wood preservatives and pesticides.	2.89 ppb 6.76 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 10 ppb
Radium-226Radium-226 is a radioactive element usually found around uranium deposits.	1.63 pCi/L 3.8 pCi/L	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L	No 5 pCi/L
AtrazineAtrazine is an endocrine-disrupting herbicide used on corn, sugarcane and sorghum; it is associated with adverse reproductive effects and toxicity to the immune system.	0.15 ppb 0.37 ppb	Yes 0.15 ppb	No 3 ppb
BenzeneBenzene is a petroleum chemical that contaminates drinking water due to emissions from petroleum and chemical industries, leaching landfills and gas storage tanks.	0.01 ppb 0.15 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 5 ppb
Radium-228Radium-228 is a radioactive element usually found around uranium deposits.	0.08 pCi/L 0.56 pCi/L	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 pCi/L	No 5 pCi/L
Combined Uranium (mg/L)Uranium is a radioactive element commonly found in most rocks; processed uranium ore is used for power generation and weapons manufacture.	11.98 ppb 17.1 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 30 ppb
Trichloroacetic acidTrichloroacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	5.92 ppb 21.8 ppb	Yes 20 ppb	No 60 ppb
Dichloromethane (methylene chloride)Dichloromethane is a widely-used paint remover, solvent and metal degreasing agent; it is discharged into the environment from the manufacture of chemicals, textiles, electronics, metals and plastics, pharmaceuticals and pesticides.	<0.01 ppb 0.09 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No 5 ppb
Lead (total)Lead is a metal that enters water by corrosion of household plumbing systems, discharge of industrial pollution and erosion of natural deposits.	0.02 ppb 0.38 ppb	Yes MCLGA non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.: 0 ppb	No
NOTE: Each dot in the above graph represents one month. * Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Other Detected Contaminants

Contaminant	Average/ Maximum Result	Health Limit Exceeded	Legal Limit Exceeded	Testing History -Tested      -Detected      -Over Health Guidelines      -Over Legal Limit*
Bromochloroacetic acidBromochloroacetic acid is a disinfection byproduct, and is formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	3.95 ppb 8.8 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Dibromoacetic acidDibromoacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	0.64 ppb 3.04 ppb	No	No 60 ppb
Monochloroacetic acidMonochloroacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	2.98 ppb 46.55 ppb	No 70 ppb	No 60 ppb
NitrateNitrate enters drinking water sources from fertilizer runoff, leaching septic tanks, and erosion of natural deposits; it is also emitted by chemical, petrochemical and metal-finishing industries.	0.18 ppm 0.8 ppm	No 10 ppm	No 10 ppm
Barium (total)Barium is a mineral that enters drinking water through drilling and mining waste runoff, discharges from chemical industries and erosion of natural deposits.	156.72 ppb 297.35 ppb	No 700 ppb	No 2000 ppb
ManganeseManganese is a naturally occurring element released from mineral deposits as well as industrial use.	6.11 ppb 13.18 ppb	No 50 ppb	No 50 ppb
CopperCopper is a naturally occuring metal and drinking water contaminant that enters tap water by corrosion of household plumbing systems and erosion of natural deposits.	1.58 ppb 3.8 ppb	No 300 ppb	No 1000 ppb
m- & p- XyleneXylene is a petroleum-derived solvent used in the printing, rubber, and leather industries, and as a cleaning agent, a thinner for paint, and an ingredient in paints and varnishes.	0.15 ppb 1.63 ppb	No 10000 ppb	No 10000 ppb
o-Xyleneo-Xylene is a petroleum-derived solvent used in the printing, rubber, and leather industries; it is also used as a cleaning agent, a thinner for paint, and an ingredient in paints and varnishes.	0.17 ppb 2.17 ppb	No 10000 ppb	No 10000 ppb
AluminumAluminum is a metal released from metal refineries and mining operations.	9.8 ppb 45.25 ppb	No 200 ppb	No 200 ppb
EthylbenzeneEthylbenzene is a pollutant from petroleum refineries and industrial chemical factories; it is also used to make plastics, and may be present as an impurity in some insecticides.	0.05 ppb 0.47 ppb	No 300 ppb	No 700 ppb
Selenium (total)Selenium is a naturally occurring element that contaminates water due to mining or petrolum refining, fly-ash from coal-burning power plants, and irrigation of arid farmland soils high in selenium.	1.36 ppb 5.9 ppb	No 50 ppb	No 50 ppb
SimazineSimazine is a widely used herbicide that has been associated with endocrine disruption and cancer in experimental studies.	0.02 ppb 0.1 ppb	No 4 ppb	No 4 ppb
Methyl isobutyl ketoneMethyl isobutyl ketone (4-Methyl-2-pentanone) is an industrial chemical used in the production of paints, pesticides, textiles, inks and rubber.	0.4 ppb 6.33 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Monobromoacetic acidMonobromoacetic acid is a disinfection byproduct regulated by EPA as one of five haloacetic acids that are formed when chlorine, chloramines or other disinfectants react with organic and inorganic matter in water.	0.04 ppb 1.15 ppb	No	No 60 ppb
Uranium-234 (pCi/L)	4.79 pCi/L 6.45 pCi/L	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
DalaponDalapon is an herbicide used on roads, railway tracks and other rights of way.	<0.01 ppb 0.12 ppb	No 200 ppb	No 200 ppb
TolueneToluene is a pollutant from petroleum refineries and a chemical used in plastics manufacturing as well as the pharmaceutical, paint and furniture industries.	0.01 ppb 0.17 ppb	No 150 ppb	No 1000 ppb
Chromium (total)Chromium is a metal that pollutes drinking water due to discharge from steel and pulp mills and erosion of natural deposits.	0.14 ppb 1.83 ppb	No 100 ppb	No 100 ppb
DibromomethaneDibromomethane is an unregulated byproduct of tap water disinfection and a manufactured chemical used in chemical synthesis and as an ingredient in fire extinguishing fluids.	<0.01 ppb 0.19 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
AcetoneAcetone is a ubiquitous industrial solvent and chemical intermediate used in manufacture of plastic, fibers, cosmetics, photographic film and many other kinds of consumer goods.	0.36 ppb 7.91 ppb	No 6000 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
1,2,4-Trimethylbenzene1,2,4-Trimethylbenzene is a chemical intermediate, industrial solvent, and component of gasoline, coal tar and petroleum products.	<0.01 ppb 0.07 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
MetolachlorMetolachlor is an herbicide applied on corn, soybeans, peanuts, cotton and pod crops.	<0.01 ppb 0.03 ppb	No 700 ppb	Legal at any levelThis is the Federal Limit. State Limits may be lower.
PentanePentane is a short, volatile hydrocarbon; it is a component of some fuels, specialty solvent, and a blowing agent used in production of polystyrene foam.	0.02 ppb 0.23 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
NitriteNitrite is a chemical that enters water from fertilizer runoff, leaching septic tanks, and erosion of natural deposits.	<0.01 ppm 0.02 ppm	No 1 ppm	No 1 ppm
ButaneButane is a component of natural gas as well as aerosols and lighter fuel, and is used as an extraction agent in the food processing industry.	1.33 ppb 1.55 ppb	No	Legal at any levelThis is the Federal Limit. State Limits may be lower.
Alpha particle activity (incl. radon & uranium)Alpha particles are a form of radiation associated with mining waste pollutants and natural sources.	7.5 pCi/L 7.5 pCi/L	No	No 15 pCi/L
Combined Uranium (pCi/L)Uranium is a radioactive element commonly found in most rocks; processed ore is used for power generation and weapons manufacture.	3.9 pCi/L 3.9 pCi/L	No	No 15 pCi/L
NOTE: Each dot in the above graph represents one month. * Water utilities are noted as exceeding the legal limit if any test is above the maximum contaminant level (MCL). Most MCLs are based on annual averages so exceeding the MCL for one test does not necessarily indicate that the system is out of compliance.

Contaminants Not Detected - 147 chemicals

1,1,1,2-Tetrachloroethane, 1,1,1-Trichloroethane, 1,1,2,2-Tetrachloroethane, 1,1,2-Trichloroethane, 1,1-Dichloroethane, 1,1-Dichloroethylene, 1,1-Dichloropropene, 1,2 Dibromo-3-chloropropane (DBCP), 1,2,3-Trichlorobenzene, 1,2,3-Trichloropropane, 1,2,4-Trichlorobenzene, 1,2-Dichloroethane, 1,2-Dichloropropane, 1,3,5-Trimethylbenzene, 1,3-Dichloropropane, 2,2,3,3,4,4,6-heptachlorobiphenyl, 2,2,3,4,6-pentachlorobiphenyl, 2,2,4,4,5,6-hexachlorobiphenyl, 2,2,4,4-tetrachlorobiphenyl, 2,2-Dichloropropane, 2,3,3,4,5,6,6-octachlorobiphenyl, 2,3,7,8-TCDD (Dioxin), 2,4,5-t, 2,4,5-TP (Silvex), 2,4-d, 2-Hexanone, 3-Hydroxycarbofuran, Acenaphthene, Acenaphthylene, Acrylonitrile, Alachlor (Lasso), Aldicarb, Aldicarb sulfone, Aldicarb sulfoxide, Aldrin, Alpha Chlordane, Aniline, Anthracene, Antimony (total), Aroclor 1016, Aroclor 1221, Aroclor 1232, Aroclor 1242, Aroclor 1248, Aroclor 1254, Aroclor 1260, Benzo[a]anthracene, Benzo[a]pyrene, Benzo[b]fluoranthene, Benzo[g,h,i]perylene, Benzo[k]fluoranthene, Beryllium (total), bis(2-ethylhexyl) phthalate, Bromacil, Bromobenzene, Bromochloromethane, Bromomethane, Butachlor, Butyl Acetate, Butyl Benzylphthalate, Cadmium (total), Carbaryl, Carbofuran, Carbon tetrachloride, Chlordane, Chloroethane, Chloromethane, Chrysene, cis-1,2-Dichloroethylene, cis-1,3-Dichloropropene, Cyanogen Chloride, Di(2-Ethylhexyl) adipate, Di(2-ethylhexyl) phthalate, Di-n-butylphthalate, Dibenz[a,h]anthracene, Dicamba, Dichloroacetonitrile, Dichlorodifluoromethane, Dieldrin, Diethylphthalate, Dimethylphthalate, Dinoseb, Diquat, Endothall, Endrin, Ethyl Methacrylate, Ethylene dibromide (EDB), Fluorene, Glyphosate, Heptachlor, Heptachlor epoxide, Hexachlorobenzene (HCB), Hexachlorobutadiene, Hexachlorocyclopentadiene, Indeno[1,2,3-cd]pyrene, Iodomethane, Isopropylbenzene, Lindane, m-Dichlorobenzene, m-Xylene, Mercury (total inorganic), Methomyl, Methoxychlor, Methyl ethyl ketone, Methyl methacrylate, Methyl Parathion, Metribuzin, Monochlorobenzene (Chlorobenzene), Mtbe, n-Butylbenzene, n-Propylbenzene, Naphthalene, o-Chlorotoluene, o-Dichlorobenzene, Oxamyl (Vydate), p-Chlorotoluene, p-Dichlorobenzene, p-Isopropyltoluene, p-Xylene, Parathion (ethyl), Pentachlorophenol, Phenanthrene, Phenols, Picloram, Prometon, Propachlor, Pyrene, sec-Butylbenzene, Silver (total), Styrene, tert-Butylbenzene, Tetrachloroethylene, Tetrahydrofuran, Thallium (total), Total polychlorinated biphenyls (PCBs), Toxaphene, trans-1,2-Dichloroethylene, trans-1,3-Dichloropropene, Trans-Nonachlor, Trichloroethylene, Trichlorofluoromethane, Trifluralin, Uranium-238 (pCi/L), Vinyl 2-chloroethyl Ether, Vinyl acetate, Vinyl chloride, Xylenes (total)

Pollution Summary

46	Total Contaminants Detected (2004 - 2007) Aluminum, Arsenic (total), Barium (total), Chromium (total), Copper, Lead (total), Manganese, Nitrate, Nitrite, Selenium (total), Dalapon, Simazine, Metolachlor, Atrazine, Butane, Acetone, Methyl isobutyl ketone, Pentane, Dibromomethane, 1,2,4-Trimethylbenzene, Monochloroacetic acid, Dichloroacetic acid, Trichloroacetic acid, Monobromoacetic acid, Dibromoacetic acid, Bromochloroacetic acid, Total haloacetic acids (HAAs), Chloroform, Bromoform, Bromodichloromethane, Dibromochloromethane, Total trihalomethanes (TTHMs), Dichloromethane (methylene chloride), Benzene, Toluene, Ethylbenzene, o-Xylene, m- & p- Xylene, Alpha particle activity (incl. radon & uranium), Combined Uranium (mg/L), Radium-226, Radium-228, Alpha particle activity, Combined Uranium (pCi/L), Uranium-234 (pCi/L), Gross beta particle activity (pCi/L)
9	Agricultural Pollutants (pesticides, fertilizer, factory farms) Arsenic (total), Nitrate, Nitrite, Selenium (total), Dalapon, Simazine, Metolachlor, Atrazine, Ethylbenzene
12	Sprawl and Urban Pollutants (road runoff, lawn pesticides, human waste) Nitrate, Copper, Lead (total), Arsenic (total), Nitrite, Dalapon, m- & p- Xylene, Dichloromethane (methylene chloride), o-Xylene, Benzene, Acetone, Butane
28	Industrial Pollutants Aluminum, Arsenic (total), Barium (total), Chromium (total), Lead (total), Manganese, Nitrate, Nitrite, Selenium (total), Butane, Acetone, Methyl isobutyl ketone, Pentane, Dibromomethane, 1,2,4-Trimethylbenzene, Dichloromethane (methylene chloride), Benzene, Toluene, Ethylbenzene, o-Xylene, m- & p- Xylene, Alpha particle activity (incl. radon & uranium), Combined Uranium (mg/L), Radium-226, Radium-228, Alpha particle activity, Combined Uranium (pCi/L), Gross beta particle activity (pCi/L)
13	Water Treatment and Distribution Byproducts (pipes and fixtures, treatment chemicals and byproducts) Total trihalomethanes (TTHMs), Total haloacetic acids (HAAs), Chloroform, Bromodichloromethane, Dibromochloromethane, Dichloroacetic acid, Trichloroacetic acid, Bromoform, Dibromoacetic acid, Monochloroacetic acid, Bromochloroacetic acid, Monobromoacetic acid, Dibromomethane
17	Naturally Occurring (naturally present but increased for lands denuded by sprawl, agriculture, or industrial development) Nitrate, Copper, Barium (total), Lead (total), Arsenic (total), Manganese, Radium-228, Radium-226, Alpha particle activity, Gross beta particle activity (pCi/L), Combined Uranium (pCi/L), Chromium (total), Alpha particle activity (incl. radon & uranium), Combined Uranium (mg/L), Aluminum, Selenium (total), Nitrite
10	Unregulated Contaminants EPA has not established a maximum legal limit in tapwater for these contaminants Lead (total), Metolachlor, Butane, Acetone, Methyl isobutyl ketone, Pentane, Dibromomethane, 1,2,4-Trimethylbenzene, Bromochloroacetic acid, Uranium-234 (pCi/L)

EPA Violation Summary

No violations were reported for this system since 2004.

Information on violations is drawn directly from EPA's national violations database in the Agency's Safe Drinking Water Information System. Analyses by others have raised questions about the quality of the information in EPA's database. For the purposes of this investigation, EWG is not showing below or including in our analyses, those violations for individual water suppliers that occurred on days for which the total number of violations assigned by EPA to that water supplier was greater than 20. This criteria was based on common characteristics of incorrect violations data as identified by water utilities, from a review of EPA's violations data by several hundred utilities prior to the release of EWG's investigation.