Nebraska wastewater operators
The steps from no certificate to a Nebraska Class L or Class I wastewater operator certificate, how to apply for and pass the exam, how to keep your certificate active and what operators earn. Every requirement links to the Nebraska Department of Water, Energy, and Environment (DWEE) Wastewater Treatment Facility Operator Certification Program, its rule, Title 197, or the Wastewater Treatment Operator Certification Act.
DWEE makes the final eligibility determination. Check with DWEE before you apply.
Why it matters
Nebraska law makes it unlawful to operate a wastewater treatment facility unless its operator is certified at the facility's classification level.
An operator is anyone who regularly makes recommendations or is responsible for process control decisions at a wastewater treatment facility. People whose duties are only laboratory testing or maintenance, or who give only general or indirect supervision, are not operators.
The operator in direct responsible charge (DRC), who makes the daily operating decisions, must be certified at the facility's class or higher. Class II and III plants also need an assistant operator certified one class lower or higher, and at Class IV plants shift supervisors serving as DRC need Class IV.
Some facilities are exempt, such as storm water ponds and onsite systems. A non-discharging (full-retention) lagoon may be exempted by DWEE for four years at a time.
A new or promoted operator has up to 12 months from the hiring date to earn the certificate the job needs, as long as they take the exam at least once within six months.
Nebraska has nine wastewater certificates: Class L, Class I, Class II, Class III and Class IV for municipal, commercial and compatible industrial (biological) plants, and Industrial I to IV for non-compatible industrial (physical or chemical) plants.
DWEE classes each plant with a point rating system based on how complex its treatment is, the population it serves and conditions in the stream it discharges to. Class L is a lagoon with 15 points or less, Class I is 30 points or less, Class II is 31 to 55, Class III is 56 to 75 and Class IV is 76 or more.
Class L to IV certificates do not cover non-compatible industrial plants, and Industrial I to IV certificates do not cover municipal plants. You need the matching type.
Title 197 has no separate collection system certificate. A system with only collection, lift stations and chlorination counts as a collection system, not a treatment plant.
Step 1
For Class L, Class I or Industrial I, Title 197 asks for one year of work experience at a wastewater treatment facility, and a high school diploma or equivalent may be substituted for that year.
DWEE's current application marks a high school diploma or GED as required and asks for the facility where you work now.
If you pass the exam before you meet the education and experience requirements, DWEE issues a provisional certificate. You can ask to have the provisional status removed once you meet them.
Step 2
Send DWEE the Application for Certification and Examination, a Citizenship Attestation Form and the $150 exam fee. Choose one level on the application.
Choose how to test: a computer-based exam at a PSI testing center, a computer-based exam at DWEE's Fallbrook office in Lincoln, or a paper exam on one of DWEE's scheduled dates.
DWEE must receive your application, attestation form and payment (check or money order) at least 30 days before the exam date you plan to attend. Applications received later may be held for the next exam. Fees are nonrefundable.
DWEE's online Credentialing Portal also lets you register and pay for exams, view your credentials, add continuing education and renew.
Step 3
DWEE publishes a list of exam preparation providers, including Sacramento State (California State University), the Nebraska Rural Water Association and the Nebraska Water Environment Association.
DWEE runs a Pre-Exam Lagoon Training on some dates, listed at $140 on the application. Some exam dates follow a training event; attending the training is not required, and you apply for the training and the exam separately.
Step 4
DWEE tells you your result in writing as soon as it is available; the application asks for your email address for exam results. A certificate is not issued until DWEE has all your documents and payment.
The owner of a Class L or Class I plant can ask DWEE for a one-year temporary certificate for a new operator within 30 days of hiring. It is tied to that operator and that plant, and the fee is $125.
Step 5
Certificates expire two years from the date they are issued, on a quarterly date: January 1, April 1, July 1 or October 1. DWEE sends a notice at least 60 days before, but renewing is your responsibility even without it. The law gives a 90-day period after expiration to renew.
To renew, earn at least 20 hours (2 CEUs) of DWEE-approved training in the two years before expiration and pay the $150 renewal fee. Up to 10 extra hours (1 CEU) can carry over to the next two years.
Training must be approved by DWEE in advance to count. DWEE keeps a list of approved courses, and you are responsible for keeping your training records and submitting your hours.
During military deployment or a catastrophic medical condition you can ask DWEE to put your certificate on hold within 30 days. When you return to work you have six months to earn your hours and renew.
Exam day
DWEE is a testing partner of the Association of Boards of Certification (ABC) and gives ABC customized exams for Nebraska certification.
You need a score of at least 70% to pass.
Exams are closed-book. ABC formula conversion tables, scratch paper and pencils are provided, and no reference material is allowed.
Bring photo ID and a non-graphical, non-programmable calculator. Cell phones and any device that can take pictures or copy material are not allowed.
DWEE schedules at least four exams a year around the state; its 2026 Schedule of Exams lists paper exams most months, mostly in Lincoln, and online testing at PSI testing centers.
If you fail, you may retest at a later exam with a new application and the $125 retest fee. After three failures in a row, you need at least 10 hours (1 CEU) of training before you retest.
DWEE gives customized exams from the Association of Boards of Certification (ABC) and hands out ABC's formula conversion tables. Operator Master's free practice questions, timed practice exam and math help are built on the WPI (formerly ABC) exam format and formula table, so use them for general wastewater knowledge and math, and check DWEE's pages for what the Nebraska exam covers. Operator Master is an independent study tool, not the official exam.
Pay
The median pay for water and wastewater treatment plant and system operators in Nebraska was $61,220 a year ($29.43 an hour) in 2025, compared with $60,020 nationally. One in ten earned $44,620 or less, and one in ten earned $76,250 or more.
These federal figures cover drinking water and wastewater operators together, at every class. Pay for a new operator is usually nearer the low end.
Moving up
These are Title 197's requirements for the Class L to IV certificates; Industrial I to IV follow the same rows. Experience means work at a wastewater treatment facility. DWEE's application also marks a high school diploma or GED as required.
From another state
If you hold a valid certificate from another recognized operator certification program with requirements DWEE's director considers similar, you may get a Nebraska certificate of an equivalent class without an exam.
Apply with the Application for Certification and Examination, choosing Reciprocity, and the $150 reciprocity fee. Reciprocity is not available if your certification has been denied, revoked or suspended.
