Median Pay by Area
- Phoenix-Mesa-Chandler
- $63,660 a year
- Tucson
- $58,390 a year
- Flagstaff
- $58,680 a year
- Prescott Valley-Prescott
- $49,730 a year
- Rest of Arizona (non-metro)
- $48,960 a year
Arizona wastewater operators
The steps from no certificate to an Arizona Grade 1 wastewater operator certificate, how to register for and pass the exam, how to keep your certificate active and what operators earn. Every requirement links to the Arizona Department of Environmental Quality (ADEQ) guide How to Become a Certified Operator or ADEQ's exam page.
ADEQ makes the final eligibility determination. Check with ADEQ before you apply.
Why it matters
ADEQ certifies operators in four classifications: Water Distribution, Water Treatment, Wastewater Collections and Wastewater Treatment. You decide which classification to test for.
For wastewater work, that means Wastewater Treatment or Wastewater Collections.
You also decide which grade to test for. Grade 1 is the starting grade.
There is a separate exam for each classification and grade level that Arizona certifies, each with its own Need-to-Know Criteria.
Step 1
Grade 1 exams require a high school diploma or GED.
To skip a grade when you have less than one year with a previous grade, contact ADEQ's Operator Certification Program for approval first.
Step 2
ADEQ highly recommends starting with the WPI Need-to-Know Criteria for your classification and grade. They describe the core skills the exam covers, the exam specifications and the reference material to study.
ADEQ keeps older editions of the certification exams for practice. They are not copies of the actual exams. Email azopcert@azdeq.gov with your name, the grade and class of test, and the date and time you want. Practice exams are given Monday to Friday, 8:30 a.m. to 4 p.m. except holidays, at ADEQ's Phoenix and Tucson offices, and can take up to 3 hours.
ADEQ's book list for wastewater includes Operation of Wastewater Treatment Plants, Volumes 1 and 2, and Operation and Maintenance of Wastewater Collection Systems, Volumes 1 and 2, from the Sacramento State Office of Water Programs; WEF's The Wastewater Operator's Guide to Preparing for the Certification Examination; and AWWA's Wastewater Operator Certification Study Guide.
Step 3
ADEQ's approved exam proctors are GateWay Community College, the City of Phoenix and Central Arizona College. Register for an exam from ADEQ's Operator Certification page.
Each proctor sets its own dates, times and locations. Follow that proctor's policy for scheduling, rescheduling, testing and canceling.
If you are already certified with ADEQ, register your exam through your personal Operator Certification Portal account.
For current certification and application fees, see ADEQ's Certified Operator fee page.
Step 4
After the exam, an Individual Mastery Report (IMR) is sent to the email your testing location has. Use the IMR to certify your exam score through ADEQ's Operator Certification Portal.
If you did not pass, use the IMR to focus on the areas where you scored low, then reschedule when you are ready.
Step 5
To renew, complete at least 30 Professional Development Hours (PDHs) every three years, or between your certificate's effective and expiration dates.
Keep a complete record of your PDHs and upload copies to ADEQ's Operator Certification Portal before you renew.
Upgrading to a higher grade does not require PDHs.
Exam day
ADEQ uses the computerized 2025 ABC exam. The exam creators are the Association of Boards of Certification (ABC) and Water Professionals International (WPI).
The exam is multiple choice with 100 scored questions, and you have three hours. Only one exam may be taken in a three-hour period.
A score of 70 percent or higher is required to pass.
Non-programmable calculators are allowed, and formula/conversion sheets are supplied at the testing site.
Operator Master has free practice questions with an explanation after every answer, a timed full-length practice exam and step-by-step math help built on the WPI formula table. It is an independent study tool, not the official exam.
Pay
The median pay for water and wastewater treatment plant and system operators in Arizona was $61,340 a year ($29.49 an hour) in 2025, compared with $60,020 nationally. One in ten earned $46,690 or less, and one in ten earned $80,040 or more.
These federal figures cover drinking water and wastewater operators together, at every grade. Pay for a new operator is usually nearer the low end.
Moving up
ADEQ's guide lists only the Grade 1 requirement. To skip a grade when you have less than one year with a previous grade, get approval from ADEQ's Operator Certification Program first.
From another state
ADEQ's How to Become a Certified Operator guide does not cover certificates from other states. Ask ADEQ's Operator Certification Program at azopcert@azdeq.gov before you apply.