For how long must bacteria results be retained according to regulations?

The retention period for bacteria results is crucial for ensuring compliance with water quality regulations and maintaining public health. Retaining these results for five years allows for adequate record-keeping in case of an outbreak or health investigation, ensuring that there is sufficient historical data to analyze trends and identify potential sources of contamination. This timeframe is in line with various regulatory requirements set forth by agencies like the EPA, which necessitate that water systems maintain records of water quality tests to ensure ongoing compliance and public safety. Retaining results longer than this may not be necessary for regular operational and compliance purposes, while shorter retention could jeopardize the ability to investigate health issues related to water quality.