Median Pay by Area
- Philadelphia-Camden-Wilmington (PA-NJ-DE-MD)
- $66,680 a year
- Pittsburgh
- $65,480 a year
- Allentown-Bethlehem-Easton (PA-NJ)
- $64,190 a year
- Harrisburg-Carlisle
- $63,680 a year
- Lancaster
- $63,630 a year
Pennsylvania wastewater operators
The steps from no certificate to a Pennsylvania wastewater operator certificate, which exams to take, how to apply to the certification board, how to keep your certificate active and what operators earn. Every requirement links to the Pennsylvania Department of Environmental Protection (DEP) Operator Certification Program or its regulations, 25 Pa. Code Chapter 302.
DEP makes the final eligibility determination. Check with DEP before you apply.
Why it matters
In Pennsylvania, only an appropriately certified operator may make process control decisions at a wastewater system. That means a certificate of the same or higher class as the system, with every subclass for the treatment technologies it uses.
A process control decision is any decision that changes or keeps the water quantity or quality of a system in a way that may affect public health or the environment.
The rules cover wastewater systems and collection systems with pump stations. They do not cover plants with a permitted average daily discharge under 2,000 gallons per day, onlot sewage systems, most industrial wastewater systems or systems that only handle stormwater.
Certificates are issued by the State Board for Certification of Water and Wastewater Systems Operators. DEP runs the Operator Certification Program.
DEP sorts wastewater systems by permitted average daily discharge flow: Class D up to 100,000 gallons per day, Class C over 100,000 gallons per day up to 1 million gallons per day (MGD), Class B over 1 up to 5 MGD and Class A over 5 MGD. Class E is a satellite collection system with a pump station.
Each Class A to D plant also has one or more subclasses for its treatment: 1 activated sludge, 2 fixed film (such as trickling filters and rotating biological contactors) and 3 treatment ponds and lagoons. Subclass 4 is a single entity collection system, and Class E always comes with Subclass 4.
Your class comes from your experience, not from a harder exam. The same exams serve every class, and you do not test again to move up from Class D to C, B or A. Adding a subclass does need its exam.
Step 1
For a treatment plant (Class A, B, C or D), you pass the Part I Wastewater General Exam and the Part II exam for each technology your plant uses. For a collection system, you pass the Class E stand-alone exam; it has no general exam.
DEP suggests asking your plant supervisor, checking your NPDES permit or asking your DEP sanitarian for your plant's class and subclasses, so you take the right exams.
You need a high school diploma or GED to be certified. The only exception is someone who was already working at a water or wastewater system before February 21, 2002.
Step 2
DEP highly recommends preparing through coursework or course material and suggests brushing up on basic math, biology and some chemistry. The knowledge each exam covers is listed in Appendix A (Need-to-Know Criteria) of DEP's Operator Certification Program Handbook.
DEP publishes Wastewater Operator Certification Training Modules and a Training Advice sheet that matches modules to the General Exam and each subclass exam.
DEP-approved courses are listed in the EarthWise Academy course catalog. Many courses approved for continuing education also help you prepare for your first exams.
A DEP-approved certificate program (at least 180 hours) or associate degree program (at least 360 hours) prepares you for the exams and cuts the experience you need. DEP posts the current list of approved programs.
Step 3
You do not need any experience or training to take the exams. Pick a date on DEP's Certification Exam Schedule and register with the approved exam provider listed for it. DEP cannot schedule you.
Approved exam providers are groups such as operator associations, colleges and consultants that host exam sessions at sites across Pennsylvania. Each charges its own fee, which varies.
DEP also charges $35 for each 4-hour exam session. You usually pay it when you apply for certification, but if you sign up for a fifth session first, DEP will ask you to pay at the exam.
You can take up to 8 tests in one 4-hour session. To cancel or change, contact the exam provider or DEP; changes are not accepted in the week before the exam without DEP's approval, and a no-show is charged by both.
Step 4
Experience comes from process control work under the supervision of a certified operator who holds the right subclasses: running and maintaining equipment, collecting and analyzing samples, doing process calculations, keeping monitoring data and recommending process changes. You should not make process control decisions yourself until you are certified.
One year of experience equals 220 working days or 1,760 hours, and shorter periods are prorated.
With a high school diploma or GED (Track 1), education can cover up to half of the experience: 1 month for every 10 contact hours of DEP-approved water or wastewater training, or 1.5 months for each college credit in DEP-approved water or wastewater coursework.
Experience at a drinking water system can count for up to half of the experience needed for a wastewater certificate.
Step 5
When you pass the exams you need, DEP mails you a pass letter and an Application for Certification to Operate Water or Wastewater Systems showing the amount you owe.
Include a Pennsylvania State Police criminal history record dated within 90 days of when the board receives your application, a copy of your diploma or GED, your experience verified by your supervisor or another certified operator, any transcripts or training certificates, and your notarized signature.
The certification fee is $150 for Class A, B, C or D, or $100 for Class E, plus $35 for each exam session you attended.
The board reviews complete applications at its meetings. Each meeting has a deadline about two weeks before it, and an application that arrives late waits for the next meeting. DEP posts each year's dates.
If you passed the exams but do not yet have the experience, the board can give you operator-in-training status. An operator in training may not make process control decisions alone until the board issues a certificate.
Step 6
A certificate is valid for three years. DEP mails a renewal application about 70 days before it expires, and the renewal fee is $60.
Wastewater Class A, B and C operators need 15 contact hours of DEP-approved continuing education in their first three-year cycle and 30 in each cycle after. Class D and E operators need 8, then 15.
Hours must be earned within the cycle and cannot be carried into the next one. A course counts only once per cycle, and there is no grace period. You can check your hours on your EarthWise Academy transcript.
Every certified operator must also complete DEP's system security course once, Securing Drinking Water and Wastewater Treatment Facilities. Not completing it means losing your certification.
If you miss your continuing education, or do not renew within two years after your certificate expires, you must apply for certification again and retake the exams.
Exam day
DEP prepares the exams and the certification board gives them through approved exam providers at scheduled sessions around Pennsylvania.
The Part I General Exam covers what every wastewater operator needs to know, whatever the plant. Each Part II exam covers one treatment technology. Each exam is scored on its own, and a passed exam stays valid unless you later have to be certified again.
DEP's handbook says the questions are multiple choice, the exams are closed book and a formula and conversion sheet is provided. Bring a non-programmable calculator and pencils.
Devices that store information, phones and other communication devices, music players and printed materials of your own are not allowed.
Wait at least a month after the exam before contacting DEP about your scores, and keep your address current with DEP so your results and paperwork reach you.
Pennsylvania's certification exams are written by DEP and given by the State Board for Certification of Water and Wastewater Systems Operators, with a formula and conversion sheet handed out at the exam. Operator Master's free practice questions, timed practice exam and math help are built on the WPI exam format and the WPI formula table, so they cover general wastewater knowledge and math, not Pennsylvania's exam questions, format or formula sheet. Use DEP's Need-to-Know criteria, training modules and approved courses as your main guide. 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 Pennsylvania was $63,310 a year ($30.44 an hour) in 2025, compared with $60,020 nationally. One in ten earned $45,670 or less, and one in ten earned $80,480 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 the high school diploma or GED (Track 1) amounts. A DEP-approved certificate program or associate degree, an associate degree in environmental or physical sciences or engineering, or a bachelor's degree in a listed science or engineering field shortens them (Track 2), but you can use only one track. In Pennsylvania, experience for a class can come from a plant of that class or up to two classes lower.
From another state
The board may certify you if you hold a valid water or wastewater operator certificate from another state, a territory, the District of Columbia or a board-approved registry: the Association of Boards of Certification (ABC) Registry, or military or Coast Guard discharge papers documenting water or wastewater operation. An expired certificate does not qualify.
Your certificate must have come from passing an exam that DEP finds comparable to its own. Your class is based on Track 1 experience at the highest comparable Pennsylvania class, with no credit for advanced education, and each subclass needs at least a year of experience with that technology.
Download the Application for Certification through Reciprocity from DEP's Documents and Forms page. It needs a criminal history record, and the fee is $150 for Class A, B, C or D, or $100 for Class E.
You cannot use reciprocity if a Pennsylvania certificate of yours was revoked or suspended, or lapsed because of missing continuing education.