Class S Water Scope: A Combined Treatment and Distribution Credential
What makes Class S unusual
Most operator classes sit on a single ladder in a single discipline. Class S is defined by the
size of the system and spans two disciplines. Under Regulation 100 it applies to a water system
serving 3,300 persons or fewer, and its authorised scope is the equivalent of the Class D
water treatment scope together with the Class 1 water distribution scope.
Confirm the operative wording and conditions with the Colorado Department of Public Health and
Environment and the WWFOCB rather than relying on any summary, including this one.
Why the combination exists
It reflects how small systems are actually staffed. At a system serving a few hundred or a few
thousand people there is rarely a treatment operator and a separate distribution operator - there
is one person, wh