2,060 systems serving 10,834,741 people
  This drinking water quality report shows results of tests conducted by water utilities in Pennsylvania, provided to the Environmental Working Group (EWG) by the Pennsylvania Department of Environmental Protection. It is part of EWG's national database that includes 47,667 drinking water utilities and 20 million test results from 45 states and the District of Columbia. 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 in protecting rivers, reservoirs, and groundwater from pollution in the first place. The information below summarizes drinking water quality for this state.

Water Utilities
Population Served
Detected Chemicals
Exceed health guidelines*
Exceed Legal Limits*
Unregulated chemicals detected
* 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.

  32 Contaminants Exceeding Health Based Limits

Contaminants detected in Pennsylvania drinking water above health guidelines, according to an Environmental Working Group analysis of data obtained from state water authorities

Number of Systems
At Any Level Above Health Limits At Any Level Above Health Limits
Total haloacetic acids (HAAs) 10,449,397 10,398,523 1,241 1,212
Total trihalomethanes (TTHMs) 10,758,511 9,889,384 1,663 779
Arsenic (total) 3,736,561 3,736,561 336 336
Radium-228 3,003,298 3,003,298 276 276
Dichloromethane (methylene chloride) 2,659,383 2,659,383 50 50
Atrazine 2,398,926 2,048,950 40 25
Tetrachloroethylene 1,763,026 1,763,026 74 74
Pentachlorophenol 1,638,977 1,638,977 5 5
Alachlor (Lasso) 1,600,040 1,600,040 2 2
Trichloroethylene 1,556,387 1,556,387 83 83

  Sources of Pennsylvania Drinking Water Contaminants

The contaminants identified in Pennsylvania drinking water come from a wide variety of sources, including agriculture, industry, water treatment plants, and polluted storm runoff from urban areas.

59 Total Contaminants Detected (2004 - 2009)
19 Agricultural Pollutants
(pesticides, fertilizer, factory farms)

Arsenic (total), Cyanide, Nitrate, Nitrite, Selenium (total), Lindane, Dalapon, Glyphosate, Simazine, Metolachlor, Atrazine, Alachlor (Lasso), 2,4-D, Foaming agents (surfactants), o-Dichlorobenzene, p-Dichlorobenzene, 1,2-Dichloropropane, Monochlorobenzene (Chlorobenzene), Ethylbenzene

18 Sprawl and Urban Pollutants
(road runoff, lawn pesticides, human waste)

Arsenic (total), Cadmium (total), Cyanide, Mercury (total inorganic), Nitrate, Nitrite, Antimony (total), Lindane, Dalapon, Glyphosate, 2,4-D, Benzo[a]pyrene, Foaming agents (surfactants), Xylenes (total), Dichloromethane (methylene chloride), p-Dichlorobenzene, Tetrachloroethylene, Benzene

47 Industrial Pollutants

Aluminum, Arsenic (total), Barium (total), Cadmium (total), Chromium (total), Cyanide, Manganese, Mercury (total inorganic), Nitrate, Nitrite, Selenium (total), Antimony (total), Beryllium (total), Thallium (total), Lindane, Di(2-ethylhexyl) phthalate, Hexachlorocyclopentadiene, Pentachlorophenol, 1,2,4-Trichlorobenzene, cis-1,2-Dichloroethylene, Foaming agents (surfactants), Xylenes (total), Dichloromethane (methylene chloride), p-Dichlorobenzene, Vinyl chloride, 1,1-Dichloroethylene, trans-1,2-Dichloroethylene, 1,2-Dichloroethane, 1,1,1-Trichloroethane, Carbon tetrachloride, 1,2-Dichloropropane, Trichloroethylene, 1,1,2-Trichloroethane, Tetrachloroethylene, Monochlorobenzene (Chlorobenzene), Benzene, Toluene, Ethylbenzene, Styrene, Alpha particle activity (excl radon and uranium), Alpha particle activity (incl. radon & uranium), Radium-226, Radium-228, Tritium, Strontium-90, Combined Uranium (pCi/L), Gross beta particle activity (pCi/L)

6 Water Treatment and Distribution Byproducts
(pipes and fixtures, treatment chemicals and byproducts)

Cadmium (total), Di(2-ethylhexyl) phthalate, Benzo[a]pyrene, Total haloacetic acids (HAAs), Total trihalomethanes (TTHMs), Vinyl chloride

17 Naturally Occurring
(naturally present but increased for lands denuded by sprawl, agriculture, or industrial development)

Aluminum, Arsenic (total), Barium (total), Chromium (total), Cyanide, Manganese, Mercury (total inorganic), Nitrate, Nitrite, Selenium (total), Alpha particle activity (excl radon and uranium), Alpha particle activity (incl. radon & uranium), Radon, Radium-226, Radium-228, Combined Uranium (pCi/L), Gross beta particle activity (pCi/L)

4 Unregulated Contaminants
EPA has not established a maximum legal limit in tapwater for these contaminants

Metolachlor, Radon, Tritium, Strontium-90

  Testing Summary for Pennsylvania

The federal government has set standards for some of the pollutants found in tap water supplies.

Contaminants reported as tested by water suppliers in Pennsylvania 92
  Contaminants tested due to federal law: 73
  Contaminants tested in addition to those required by federal law: 19
  Violation Summary for Pennsylvania

Data from the U.S. Environmental Protection Agency includes the following violations of federal standards in Pennsylvania since 2004

Violation Type Number of Violations
Failure to monitor regularly 13,063
Monitoring and Reporting Disinfection Byproduct Rule 8,126
Failure to monitor, Routine Major (Coliform bacteria) 1,969
Failure to report information to the public or state agency in the Consumer Confidence Report 1,881
Failure to monitor or report, Routine/Repeat (Indicators of microbial or virus contamination) 1,598
Public Notification Violation for National Primary Drinking Water Regulations 1,146
Filter Turbidity Reporting 661
Over maximum contaminant level, Average 514
Failure to monitor or report, Routine/Repeat (Indicators of microbial or virus contamination) 422
Inadequate reporting of information to the public 410
Follow-up and Routine Tap Sampling 309
Maximum contaminant level, Monthly (Coliform bacteria) 276
Failure to monitor, Routine Minor (Coliform bacteria) 154
Treatment Technique Precursor Removal 126
Treatment Technique (Surface Water Treatment Rule) 117
Failure to monitor, Repeat Minor (Coliform bacteria) 98
Over maximum contaminant level, Single Sample 66
Initial Tap Sampling for Lead and Copper 63
Failure to monitor: Check/Repeat/Confirmation sampling 52
Failure to monitor, Repeat Major (Coliform bacteria) 37
Maximum contaminant level, Acute (Coliform bacteria) 28
Optimal Corrosion Control Treatment Study Recommendation 26
Monitoring & Reporting of Filter Profile/Comprehensive Performance Evaluations Failure 22
Non-Acute maximum residual disinfectant level 21
Excess Turbidity at 1 NTU 21
Excess Turbidity at 0.3 NTU 10
Water Quality Program Entry Point Non-Compliance 4
Optimal Corrosion Control Treatment Installation/Demonstration 3
Record Keeping Violation 2
Initial Water Quality Parameter Monitoring and Reporting 1

Sources : EWG (Environmental Working Group)