2006 Annual Compliance Report
of Missouri Drinking Water Systems

The Annual Compliance Report of Missouri Drinking Water Systems for 2006 3.35MB , published by the Missouri Department of Natural Resources, is now available. The report describes the extent of violations by Missouri public water systems during 2006.  The report was put together by the department's Public Drinking Water Branch.

This report covers Missouri’s 2,771 public water systems. Overall, the number of violations by Missouri’s public water systems remained fairly constant from 2005 to 2006. The percent of population served by community water systems in compliance with all health-based standards stands at 95 percent, meeting the U. S. Environmental Protection Agency’s target of compliance by 2008. 

Some significant changes for 2006 in comparison to 2005 include:

  • Maximum Contaminant Level, or MCL, violations for total coliform bacteria decreased
    8 percent from 425 to 390.
  • Acute MCL violations for fecal coliform/E.coli increased 50 percent from 20 to 30.
  • Major monitoring violations of the Total Coliform Rule increased 3 percent from
    787 to 807.

Many public water systems perform testing beyond that required by the state. A public water system, by definition, provides water for human consumption to at least 15 service connections or serves an average of 25 people for at least 60 days each year. Water testing for smaller systems serving fewer people is done by county sanitarians and the Missouri Department of Health and Senior Services, rather than the Department of Natural Resources.

There are three basic types of public water systems.

  • The first is a community system, where people live and consume the water on a daily basis. A community system could serve the residents of a large city, rural water district or a small mobile home park or subdivision.
  • The second is a non-transient, non-community system, such as a school or factory, where people drink the water on a daily basis, but do not reside there.
  • The third is a transient, non-community system, such as a restaurant, resort or campground that would not be a regular source of drinking water for most of its pass-through customers.

The Annual Compliance Report lists all systems with MCL violations and chronic monitoring violators of the Total Coliform Rule. A number of systems missed collecting samples for one or two months; few systems missed sampling for three or more months. Only 88, or 3 percent of Missouri systems were listed as Significant Noncompliers for 2006.

For all violations, public water systems are required to notify their customers long before the department issues the Annual Compliance Report and community systems send out their Consumer Confidence Report. The method of notification varies by the violation and system type. Water suppliers must then report back to the department how the public notice was done and provide a copy for the system’s file. When problems are found, the department works closely with public water systems to help them return to compliance in a timely manner. The following table summarizes the violation statistics from the 2006 Annual Compliance Report.

Contaminant Group/Rule Type of Violation Number of Violations Number of Systems with violations
Organic Chemicals Monitoring 126 6
Organic Chemicals MCL * 1 1
Disinfection By Products Monitoring 0 0
Disinfection By Products MCL * 78 22
Inorganic Contaminants Monitoring 66 6
Inorganic Contaminants MCL * 6 2
Nitrate Monitoring 50 50
Nitrate MCL * 0 0
Radionuclides Monitoring 66 22
Radionuclides MCL * 160 25
Total Coliform Rule Monitoring 842 472
Total Coliform Rule
(acute and non-acute)
MCL * 422 269
Surface Water Treatment Monitoring 0 0
Surface Water Treatment Treatment 7 5
Lead and Copper Monitoring 126 126
Lead and Copper Treatment 1 1
Consumer Confidence Report Reporting 85 85
* MCL = Maximum Contaminant Level

The 2006 Annual Compliance Report is available on the Web or by writing to the address at the bottom of this page or by calling 800-361-4827 or 573-751-5331.