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Wastewater Operator Certification Program

Wastewater treatment plants (WWTP) serve an essential function to protect public health and the environment from contaminated water leaving homes and businesses. Competent, trained, and certified operators must run these plants. We assure qualified operators fill this role through evaluating certification requirements and ongoing professional training.

How do I get certified?


Download application then mail it.

Remember to:

  • Type or write clearly in ink.
  • Apply for the level you qualify for.
  • Complete all five pages in full detail.
  • Hand sign and date affidavit (even if you have no operating experience).
  • Include all supporting documents and a $50 application fee.

What happens next?

What exam level do I qualify for?

All levels require a high school diploma or GED. WWTP operating experience can be substituted. "Operating experience" means the routine performance of duties, onsite in a WWTP, that affect plant performance or effluent quality. Continuing Education Units (CEUs) can be substituted for post high school education requirements.
Certification level Required operating experience Required post high school education

Relevant substitutions for post high school education

Relevant substitutions for experience

Excess operating experience substitution for education
Operator in Training 3 months --- 3 CEUs or college credits --- ---
Group I 1 year --- --- --- ---
Group II 3 years ---

Up to 1.5 years
(67.5 CEUs or college credits)

Up to 1.5 years based on:

1 year = 1 year


Group III 4 years
(At least 2 years at a class II plant or higher)
90 relevant CEUs or college credits

Up to 2 years
(90 excess CEU/college credits)


Up to 2 years based on:

1 year = 1 year


Up to 90 CEU/credits based on:

1st 45 CEU/credits = 1 year experience

2nd 45 credits = 3 years experience


Group IV 4 years
(At least 2 years at a class III plant or higher)
180 relevant CEUs or college credits Up to 2 years
(90 excess CEU/college credits)

Up to 2 years based on:

1 year = 1 year

Up to 180 CEU/credits based on:

1st 90 CEU/credits = year experience

2nd 90 CEU/credits = years experience

What counts as relevant experience?

Included but not limited to:

  • Boiler operator
  • Building/equipment maintenance
  • Engineering
  • Environmental or engineering branch of federal, state, county, or local government
  • Environmental or operations consultant  
  • Laboratory technician
  • Machinist
  • Water distribution manager
  • Water treatment plant operator 
  • Welding
  • Wastewater collection operator
  • Wastewater pump operator

What counts as relevant education?

To substitute education for operating experience, education credits or Continuing Education Units (CEUs) must be in excess of the required education. 

  • 1 year = 45 CEUs/quarter credits or 30 semester credits
  • 1 month = 4 CEUs

Frequently asked questions

How do I get certified with no WWTP operating experience?
How do I stay certified?
Where can I view my transcripts?
Do you offer a course to become an operator?
How can I study for the exam?
How can I get my training approved for CEUs?
Does my out-of-state license exchange for Washington?

Where to send your application materials:

Correspondence/professional growth documents



Department of Ecology
Wastewater Operator Certification
PO Box 47696
Olympia, WA 98504-7696

Payments (applications and renewals)