Public Drinking Water Branch
Chronic Monitoring Violations
The Missouri Department of Natural Resources routinely posts a list of drinking water systems that have chronically failed to do required bacteriological testing. The department requires all public water systems to test for bacteria at least once a month to verify that these systems are providing safe drinking water to the public. While failing to monitor does not necessarily mean that the water is unsafe, routine testing is a crucial part of maintaining a safe water supply.
The systems listed have at least three major monitoring violations in a 12-month period. The reports below give the most recent bacteriological results and any maximum contaminant level violations in the system's history since 1992.
Bacteriological testing can be the first step in identifying and correcting a problem. The next step is to investigate the cause of any bad samples and perform corrective action, such as disinfecting and flushing the system. When a public water system has both a record of failure to monitor and a history of MCL violations, department staff are concerned about the unknown quality of the drinking water. Failing to monitor can result in ongoing bacteriological problems. Often, informing the public of the system's chronic failure to monitor will prompt a system to routinely submit samples.
The vast majority of community and non-community public water systems in the state comply with all monitoring requirements and meet all drinking water standards. Chronic violators are the exception rather than the rule. There are approximately 2,800 public drinking water systems in Missouri and the number of violators listed is usually less than 1 percent of these.
These systems' owners have been sent multiple violation notices in addition to certified letters informing them that chronic failure to monitor is unacceptable. Department staff also routinely make frequent on-site inspections and attempt to reach an agreement with the responsible parties to ensure sampling requirements will be met. If compliance with Missouri's drinking water law is still refused, more stringent enforcement action is pursued through legal channels.
The type of bacteria monitored is called total coliform bacteria. These are common in the environment and generally not harmful by themselves. They do indicate the water may be contaminated with organisms that can cause disease. Disease symptoms include diarrhea, cramps, nausea, possible jaundice and associated headaches and fatigue. The presence of these bacteria can result from a number of problems. These could be due to an improperly constructed or deteriorating well, inadequate water treatment, or contamination in the distribution system, including water towers and the mains that distribute the water.
If a sample tests positive for total coliform bacteria, further testing is then performed for fecal coliform or E. coli, bacteria which can directly cause gastrointestinal illness. Most samples that test positive for total coliform test negative for fecal coliform or E. coli. The total coliform positive samples that are listed tested negative for fecal coliform or E. coli unless specifically stated otherwise.
Counties with systems listed are presented in alphabetical order. Systems are given in alphabetical order within each county. Unless otherwise noted, these establishments are open year-round. The cities and counties are given as location references only. Counties with a number of systems listed have a large number of public water systems, most of which are in compliance with drinking water regulations.
For more information, contact the department's Water Protection Program, Public Drinking Water Branch at 800-361-4827 or 573-751-5331.