This webpage lists the Instructions (template notices) and required (mandatory) public notice health effects language that a public water supply system must use when notifying the public of a violation that has happened in the system. There are different types of violations: maximum contaminant level violation, maximum residual disinfectant level, treatment technique violation, monitoring violation, and reporting violation.
- A maximum contaminant level (MCL) violation occurs when the level of a contaminant in drinking water delivered to any user of a public water supply system is above the maximum permissible level.
- A maximum residual disinfectant level (MRDL) violation occurs when the level of a disinfectant added for water treatment is above the maximum permissible level at a consumer's tap in the distribution system.
A treatment technique (TT) violation occurs when a treatment process required to minimize the level of a contaminant in drinking water is not maintained.
- A monitoring violation (MV) occurs when a required compliance sample was not collected during the specified time period.
- A reporting violation (RV) occurs when a required reporting activity is not completed within the specified time period.
Public notice is also required when a health advisory is exceeded for a contaminant that is not otherwise regulated, such as manganese.
For more information:
Anne Lynam, Environmental Specialist Senior
515-725-0280 or Anne.Lynam@dnr.iowa.gov