Delaware Backflow Prevention Tester Certification: Renewal Requirements

Regulating agency
Delaware Division of Public Health, Office of Drinking Water
Renewal cycle
Not published by the agency. Confirm directly with Delaware Division of Public Health, Office of Drinking Water.
CE required
Varies by local jurisdiction
Renewal fee
Varies by local jurisdiction
Regulation level
Local (city / county / water purveyor)

Last verified: 2026-07-14

Who regulates backflow tester certification in Delaware

There is no single statewide credential in Delaware: requirements are set locally by cities, counties, or water purveyors. Contact your local water purveyor for the rules that apply to you.

The authority for backflow tester credentials in Delaware is Delaware Division of Public Health, Office of Drinking Water. 16 DE Admin. Code 4462 §21.0 only requires testing by "an individual appropriately trained and experienced" and names no certifying body, cycle, CE, or fee. Acceptance is purveyor-by-purveyor: Sussex County and the City of Dover require ASSE-certified testers; the City of Wilmington uses a third-party administrator (HydroCorp). Where ASSE 5110 is accepted, ASSE's own national policy is a 3-year cycle with an 8-hour recertification class, but that is ASSE policy adopted by some purveyors, not a Delaware-mandated cycle.

How often you need to renew

Delaware Division of Public Health, Office of Drinking Water does not publish a fixed statewide renewal cycle online. Renewal timing is set by your local jurisdiction.

Continuing education and retesting requirements

Continuing education requirements vary by local jurisdiction in Delaware.

Renewal deadline and grace period

The agency does not publish a formal grace period online. Treat your expiration date as hard: Water purveyors generally stop accepting test reports from testers whose certification has lapsed, and many jurisdictions require retaking the full certification course instead of a simple renewal once the credential expires. Confirm the exact grace period, if any, with Delaware Division of Public Health, Office of Drinking Water well before your expiration date.

How to renew, step by step

  1. Confirm your exact expiration date on your certification card or with Delaware Division of Public Health, Office of Drinking Water.
  2. Complete any required refresher course or continuing education for your jurisdiction.
  3. Submit the renewal application to the local authority or water purveyor that issued your credential before the deadline.
  4. Keep your test kit calibration certificate current: most jurisdictions require annual gauge calibration alongside a valid tester credential.

Frequently asked questions

How often do I need to renew my backflow tester certification in Delaware?

Delaware Division of Public Health, Office of Drinking Water does not publish a fixed statewide renewal cycle online. Renewal timing is set by your local jurisdiction.

Who regulates backflow tester certification in Delaware?

Delaware Division of Public Health, Office of Drinking Water. There is no single statewide credential in Delaware: requirements are set locally by cities, counties, or water purveyors. Contact your local water purveyor for the rules that apply to you.

Is backflow tester certification the same in every county in Delaware?

No. In Delaware, requirements are set entirely at the local level, so the renewal cycle, approved courses, and fees can differ from one jurisdiction to another.

What happens if my Delaware backflow tester certification expires?

Water purveyors generally stop accepting test reports from testers whose certification has lapsed, and many jurisdictions require retaking the full certification course instead of a simple renewal once the credential expires. Confirm the exact grace period, if any, with Delaware Division of Public Health, Office of Drinking Water well before your expiration date.

Official source

Data on this page was verified on 2026-07-14 against:

Compare with nearby states