100+ Free OR Water/Wastewater Operator Practice Questions
Pass your Oregon Water and Wastewater Operator Certification exam on the first try — instant access, no signup required.
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About the OR Water/Wastewater Operator Exam
The Oregon water and wastewater operator certification exam covers OAR 340-049 (wastewater) and OAR 333-061 (drinking water), water treatment processes, wastewater treatment, Willamette River TMDL requirements, distribution and collection systems, laboratory testing, and safety.
Questions
100 scored questions
Time Limit
2-3 hours
Passing Score
70%
Exam Fee
Per OAR 340-049-0065 fee schedule (Oregon DEQ (wastewater) / Oregon Health Authority (drinking water))
OR Water/Wastewater Operator Exam Content Outline
State Laws & Regulations
OAR 340-049, OAR 333-061, DEQ/OHA dual certification, TMDLs, and NPDES requirements
Water Treatment
Coagulation, filtration, disinfection (chlorine/UV/ozone), and membrane treatment
Wastewater Treatment
Activated sludge, SBR, MBR, nutrient removal, and sludge management
Distribution & Collection
Pipe materials, pumps, seismic considerations, I/I management, and hydraulics
Laboratory & Safety
Water quality testing, sampling, record-keeping, confined space, and wildfire impacts
How to Pass the OR Water/Wastewater Operator Exam
What You Need to Know
- Passing score: 70%
- Exam length: 100 questions
- Time limit: 2-3 hours
- Exam fee: Per OAR 340-049-0065 fee schedule
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
Frequently Asked Questions
Who administers Oregon water operator certification?
Oregon splits certification: DEQ certifies wastewater operators (Grades I-IV under OAR 340-049) and OHA certifies drinking water operators (Levels 1-4 under OAR 333-061).
What happens after failing the Oregon exam twice?
After two failures within 12 months, OHA may require completion of an approved exam preparation course before allowing a third attempt.
What is the SWOTC program?
The Small Water Operations Technical Certification (SWOTC) program provides specialized training for small system operators, facilitated by the Oregon Association of Water Utilities (OAWU).