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Delaware Distribution Operator Certification: Class E and Consecutive Systems

What Delaware's Class E distribution credential covers and why consecutive water systems are common in the state.

Delaware Distribution Operator Certification: Class E and Consecutive Systems
What Class E Covers
Delaware's Class E credential is specifically for operators of distribution and consecutive water systems. Unlike most states, Delaware does not maintain a multi-tier A-D distribution ladder — Class E is the state's single distribution-specific credential, issued by DHSS's Office of Drinking Water.
What Is a Consecutive System?
A consecutive system buys finished (already-treated) water from another public water system and distributes it to its own customers, without doing any treatment of its own. The operator's job is purely about moving water safely through pipes, valves, storage, and pressure zones — not about treatment chemistry.
Consecutive systems are especially common in Delaware because:
  • The state is small and geographically compact, so it's often more eff

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