Distribution certification levels
Water Distribution Grade 1 — Entry-Level Operator
Entry-level ABC/WPI water distribution practice — system operation and maintenance, water quality (residual, cross-connection, sampling), basic hydraulics, pumps and storage, safety, and operator math.
Grade 2Water Distribution Grade 2 — Intermediate Operator
Intermediate ABC/WPI water distribution practice — operation and maintenance, water quality and cross-connection control, hydraulics and pumps, storage, safety, regulations, and one-step operator math.
Grade 3Water Distribution Grade 3 — Advanced Operator
Advanced ABC/WPI water distribution practice — diagnose-and-correct operation, distribution hydraulics, water quality and nitrification control, pumps and storage, safety, regulations, and operator math.
Grade 4Water Distribution Grade 4 — Advanced / Large-System Operator
Top-grade ABC/WPI water distribution practice for large, multi-pressure-zone systems — advanced operation, hydraulics, water quality, pumps and storage, safety, regulations, and operator math.
Find your state's requirements
Class names and exam rules vary by state. See how these tests map to your state's distribution operator classes on the state pages.
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