(1) Public water supply systems must undergo an initial sanitary survey by June 29, 1994, for community systems and nontransient noncommunity systems, and by June 29, 1999, for transient noncommunity water systems. Thereafter, transient noncommunity water systems must undergo another sanitary survey at least once every five years, and all other public water supply systems must undergo another sanitary survey at least once every three years. The department must review the results of each sanitary survey to determine whether the existing monitoring frequency is adequate and what additional measures, if any, the system needs to undertake to improve drinking water quality.

(2) Sanitary surveys must be performed by the department or an agent approved by the department. The supplier is responsible for ensuring the survey takes place.