Providing Safe Drinking Water 

in America: 2004 National 

Public Water Systems Compliance 

Report - Fact Sheet 

What is the scope of the report? The report is the ninth in a series (beginning with 

calendar year 1996) of annual reports from EPA. The National Public Water System 

Compliance Report for 2004 describes how the Environmental Protection Agency (EPA) and its 

state and tribal partners are meeting the goal of ensuring that Americans receive safe drinking 

water from public water systems (PWS). The report also discusses the data we use to measure 

our success and the progress we are making in our efforts to increase its reliability and 

completeness. 

Additionally, the report summarizes PWS compliance in Indian country, including violations on 

Indian reservations, EPA’s enforcement and compliance assistance activities with respect to 

Tribal PWS, and the financial assistance EPA has provided to facilitate the provision of safe 

drinking water to Tribes. Appendix B of the report summarizes, in table format, the annual 

reports that each State must prepare discussing drinking water violations at PWS in their 

jurisdictions. 

Who are the potential users of the report? The target audiences for the report are 

State and EPA drinking water regulators and environmental professionals. Others who may find 

value in this report include anyone else who may be interested in a summary of PWS 

compliance. 

PWS COMPLIANCE 

The report concludes that most Americans received drinking water from public water systems 

that recorded no significant violations in 2004. Ninety-four percent of America’s public water 

systems reported no violations of a health-based drinking water standard, and 76% of the 

populations served by public water systems received drinking water from public water systems 

with no reported significant violations in 2004. 

This report uses information from the Federal Safe Drinking Water Information System 

(SDWIS/FED), the national database in which EPA records information the states are required to 

report on PWS compliance. For the national public water system compliance reports, EPA 

examines SDWIS/FED records of violations of primary drinking water regulations that specify: 

1) the maximum permissible level of a contaminant in water that is delivered to any user of a 

public water system (Maximum Contaminant Level or MCL); 2) techniques for treating water to 

Fact Sheet December 2006 
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make it safe; 3) monitoring and reporting requirements (how and when water must be tested and 

the results reported); and 4) significant user notification violations.1 While SDWIS/FED collects 

information on monitoring and reporting violations, only “significant” monitoring and reporting 

violations are counted in this report. A “significant” monitoring and reporting violation occurs, 

with rare exceptions, when no samples are taken or no results are reported during a compliance 

period. 

Findings for National Summary 

• In 2004, 158,802 public water systems together served over 296 million users. The 

actual number of individuals served was smaller, because millions of Americans drank 

water from, and were counted as users by, more than one public water system during the 

course of the year. 

Percentage of Systems by Type 

33% 

12% 

55% 

Community 

Transient Non-Community 

Non-Transient Non-Community 

• Most public water systems were small, but large systems served a majority of the people 

who drank water from a public water system. 

Size vs. Users Served 

100% 94%

80%

60%

40%

20%

0% 

2% 

77% 

14% 

Small Systems Large Systems 

Percentage of Systems Percentage of Users Served 

This report tabulates only “significant” monitoring and reporting and notification (e.g., CCR) violations. Table A–1 of the National Public 

Water System Compliance Report presents descriptions of significant monitoring violations for the different drinking water regulations. 

Fact Sheet December 2006 

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• The primacy states reported either a health-based violation, a significant monitoring and 

reporting violation, or a significant CCR violation at 41,310 public water systems in 

2004. 

• The vast majority of the 132,573 violations (there may be more than one violation at each 

noncomplying system) the states reported to SDWIS/FED in 2004 were for a public 

water system’s significant failure to monitor and report, rather than health-based MCL or 

treatment technique violations detected and reported by a system. 

• 94% of America’s public water systems reported no violations of a health-based drinking 

water standard in 2004. The Maximum Contaminant Level for the Total Coliform Rule 

(TCR) is the health-based standard most frequently violated. 

• 76% of the population served by public water systems received drinking water from a 

system that reported no violations of a health-based standard, was not cited for a 

significant violation of a monitoring and reporting requirement, and issued a consumer 

confidence report, if required. 

Users Served by PWS 

Without Reported Significant Violation 

24% 

76% 

Users Served by PWS without Reported 

Significant Violation 

Users Served by PWS with Reported 

Significant Violation 

• 87% of community water systems complied with the Consumer Confidence Report Rule. 

• One violation of a variance or exemption was reported to SDWIS/FED during 2004. 

• EPA designated 16,688 PWS as significant noncompliers. Over 90% of these systems 

served fewer than 3,300 users. During the 2004 calendar year, States and EPA addressed 

4,392 significant noncompliers (SNCs). 36% of the SNCs addressed were newly 

identified SNCs in 2004. 

• Approximately 22,500 (21%) out of over 106,000 non-community water systems had 

significant violations. 

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• Fifty-two (21%) out of 248 larger non-community water systems serving more than 3,300 

users had significant violations. Together these 52 non-community systems served only 

about 464,000 (1.9%) users of the 24 million users served by non-community water 

systems. 

• Approximately 18,700 (36%) out of the over 52,000 community water systems had 

significant violations. Of the 272 million users served in their primary residence by 

community water systems, approximately 69 million received their water from one of the 

violating community water systems. 

• Approximately 2,100 (25%) of the more than 8,600 larger community water systems 

serving more than 3,300 users had significant violations. These violating larger 

community systems served more than 61 million (22%) of the 272 million users served in 

their primary residence by community water systems. 

• Of the approximately 44,000 community water systems serving 3,300 users or less in 

their primary residence, over 16,600 (38%) had significant violations. Over 7.8 million 

users were served by these small community water systems. 

Findings for Indian Country 

• In 2004, 818 public water systems in Indian country served 681,541 users. 

• 95% of the public water public water systems in Indian country were small (serving less 

than 3,300 users). 

• 508 of the 818 PWS had health-based or significant reporting violations. 

Systems with Reported Significant Violations 

38% 

62% 

Violations of Some Kind 

No Reported Violations 

• 89% of public water systems in Indian country reported no violations of a health-based 

drinking water standard in 2004. 

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• 89% of violations reported in 2004 were for a public water system’s significant failure to 

monitor and report, rather than for a health-based MCL or a treatment technique violation 

detected and reported. 

• 59% of tribal community water systems complied with the Consumer Confidence Report 

Rule. 

Data Quality 

The data used in this report came from EPA’s national SDWIS/FED database. SDWIS/FED is 

composed of data that primacy states are required to submit to SDWIS/FED each quarter. EPA 

periodically conducts data verifications (independent, on-site audits) of primacy state and tribal 

drinking water programs to ensure that the primacy state is determining compliance in 

accordance with Federal regulations. EPA’s review showed that the quality of the information 

the states reported to SDWIS/FED is improving, but the data are incomplete. This finding 

principally reflects differences between state and EPA regulatory interpretation rather than a 

preponderance of data management issues. 

EPA’s analysis of the data verifications found: 

• 95% of all inventory data in SDWIS/FED was accurate and complete. 

• Most of the discrepancies between apparent and reported violations are because of 

unrecorded and unreported violations. This accounts for 62% of all discrepancies related 

to maximum contaminant level/treatment technique violations and 86% of all 

discrepancies related to monitoring and reporting violations. 

• Only 27% of apparent monitoring and reporting violations had been reported to 

SDWIS/FED. 

• 65% of the apparent MCL/treatment technique violations had been reported to 

SDWIS/FED. 

• SDWIS/FED contained accurate and complete information on 82% of the enforcement 

actions found in the states’ records. 

Conclusions/Recommendations 

Most Americans received water from systems which reported no violations of health-based 

standards, and for which the states reported no significant violations of monitoring and reporting 

requirements. 

States and EPA should continue working together to address significant violations of monitoring 

and reporting and notification requirements. 

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States and EPA should continue working together to address violations of MCL and treatment 

technique requirements. 

EPA continues to work with its state partners to identify and resolve any problems that may have 

produced data discrepancies in the past and to ensure that complete and accurate documentation 

is available to help assess the safety of the nation’s drinking water. The following steps have 

been recommended: 

• The drinking water violation data has shown improvements from the 1996-1998 

timeframe to the 1999-2001 timeframe. EPA is drafting the current Data Reliability 

Report for the 2002-2004 timeframe. EPA has set a goal of 90% for data quality and is 

working closely with the Association of State Drinking Water Administrators (ASDWA) 

to implement an action plan that will help the drinking water program achieve this goal. 

• The workgroup comprised of EPA and ASDWA should continue its efforts to implement 

its updated 2003 Data Reliability Analysis and Action Plan (DRAAP). Implementation 

of the plan will begin in 2005. 

• Using the 2003 DRAAP, EPA should continue to encourage states through negotiated 

grant conditions to follow quality assurance/quality control plans for drinking water 

violation data reported to EPA and address the differences in interpretation of the 

regulation. 

• EPA should work with all states to implement the Agency Quality Management Order. 

• EPA should continue efforts to modernize the SDWIS database to reduce data quality 

problems from data entry to transmission in the future. SDWIS Modernization focused 

on changes to make the quality checking function available to states before they send data 

to EPA. Currently this quality checking function is only available to EPA at the 

receiving end. 

Where is the report available? 

Electronic: An electronic version of the report is available on EPA’s website containing

compliance data and other information about Local Government Services and Operations: 

http://cfpub.epa.gov/Compliance/resources/reports/accomplishments/sdwa/ 

Paper Copy: A limited number of hard copies of the report are available from the National 

Service Center for Environmental Publications (NSCEP) located in Cincinnati, Ohio. The report 

(Document Number: EPA 305-R-06-001) can be ordered online at 

http://www.epa.gov/ncepihom/index.htm or by calling (800) 490-9198. 

Fact Sheet December 2006