Median Pay by Area
- Barnstable Town
- $73,460 a year
- Boston-Cambridge-Newton (MA-NH)
- $73,330 a year
- Worcester
- $67,190 a year
- Springfield
- $66,200 a year
- Pittsfield
- $61,230 a year
Massachusetts wastewater operators
The steps from no license to a Massachusetts Grade 1 wastewater treatment plant operator license, how to take the exam with PSI and apply through NEIWPCC, how to keep your license active and what operators earn. Every requirement links to the Massachusetts Department of Environmental Protection (MassDEP), its Board of Certification of Operators of Wastewater Treatment Facilities, the board's rule (257 CMR 2.00) or NEIWPCC, which runs the program for MassDEP.
MassDEP makes the final eligibility determination. Check with MassDEP before you apply.
Why it matters
Massachusetts law sets up a Board of Certification of Operators of Wastewater Treatment Facilities within MassDEP to make sure wastewater treatment systems and facilities are properly managed, operated and maintained.
Under 257 CMR 2.00, no one may manage, operate or maintain a wastewater treatment facility unless the person in charge holds a valid certificate from the board. A facility that runs more than one shift needs a certified operator of the right grade on each shift.
You do not need a license to work at a wastewater facility, but the people in responsible charge must be certified to the proper grade.
A few small systems are exempt, such as lime chip neutralization, neutralizing less than 100 gallons a day, small-scale silver recovery, gravity oil/water separators and closed loop systems.
Massachusetts has Municipal Grades 1 to 4, Industrial Grades 1 to 4, Combined Grades 5 and 6, and Grade 7. Grade 7 is the highest and is given by the board, not by exam.
Municipal licenses are for plants that use a biological process, such as domestic wastewater treatment. Industrial licenses are for physical and chemical treatment, such as pH adjustment and metals removal. Through Grade 4 the two are separate; the Combined grades cover both.
The board classifies each treatment facility from Class 1 to Class 7 by adding points for the treatment units it has. The chief operator needs a license equal to the plant's grade.
The rule covers treatment facilities; its definition of a wastewater treatment facility does not include sewer systems, and it sets no separate collection system grade.
Step 1
Training is recommended but not required. NEIWPCC's course catalog lists recommended courses for each exam, and its exam reference list names the study manuals for each subject.
You may take the exam for any grade. You do not need experience to sit the exam; experience decides your license status after you pass.
Step 2
Schedule directly with PSI on its Massachusetts Wastewater Operators page or by calling 833-256-1420. Exams are given only at PSI test centers, by appointment, Monday through Saturday.
PSI lists the fee for each exam on its test page and takes payment by credit card when you book. Fees are not refundable or transferable.
You can reschedule once at no charge if you contact PSI at least two business days before your appointment. Arriving more than 15 minutes late forfeits the exam and its fee.
Step 3
After you pass, mail the Application for Wastewater Treatment Plant Operator License to NEIWPCC in Lowell with a copy of the first page of your score report, a copy of your driver's license or state ID and the $30 administrative fee.
List your wastewater jobs and duties on the form's Statement of Qualifications. If you leave that section blank, you receive When and If status.
Your license shows a status. When and If means you passed but are not working at a treatment facility. Operator-in-Training means you work at a facility but do not yet have the experience for your grade. Full means you have the experience.
To move up a status, send the board a Status Change Form through NEIWPCC showing your job duties and experience.
Step 4
For good cause, the board may grant emergency certification so an operator can work in a position at a specific facility that their license does not cover. It lasts no longer than six months, cannot be renewed and is not granted to employees or managers of contract operations firms. The facility sends a letter with the request, and the fee is $30.
Provisional certification is only for an operator who meets every requirement except the exam, after failing it and after an emergency certification has expired. It lasts no more than six months and cannot be renewed. The fee is $35.
Step 5
All Massachusetts wastewater operator licenses expire on December 31 of every odd-numbered year. Every operator, active or inactive, must renew and pay the renewal fee.
NEIWPCC mails renewal invoices. The renewal fee is $75, and a $30 late fee applies to invoices postmarked after December 31.
Active operators need 20 training contact hours (TCHs) each two-year cycle; the current cycle runs January 1, 2026, to December 31, 2027. Operators newly licensed in 2027 need 10. Hours cannot be carried over.
No more than 10 TCHs can be safety training. Passing a Massachusetts wastewater exam counts as 10 TCHs, and courses must be approved by the board with a BC code.
If you are not working as an operator, you can go inactive: no TCHs, but you still renew. To become active again, earn 10 TCHs in the same calendar year and send a Status Change Form.
The board may revoke the license of an operator who does not pay the renewal fee or earn the required hours. Getting it back takes a written exam.
Exam day
Massachusetts has ten computer-based exams: Municipal Grades 1 to 4, Industrial Grades 1 to 4 and Combined Grades 5 and 6. NEIWPCC offers them with WPI (formerly ABC) and the board through PSI. ABC develops the exams.
Questions are multiple choice, A to D. NEIWPCC's slides say Grade 1 and 2 exams have 50 questions and Grade 3, 4, 5 and 6 exams have 100.
To pass, you need 66% on Grade 1 and 2 exams, 65% on Grade 3, 4 and Combined Grade 5 exams, and 70% on the Combined Grade 6 exam.
Pencils and the ABC formula table booklet are handed out at check-in. Bring a silent, non-programmable calculator without an alphabetic keypad or printing, and two forms of ID, one a current government photo ID.
If you do not pass, you can retake the exam as many times as you like. Wait two business days between attempts and pay the fee each time.
Massachusetts gives its own Municipal, Industrial and Combined grade exams, developed by ABC (now WPI), and hands out the ABC formula table at the test center. 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 use them for general wastewater knowledge and math, and use NEIWPCC's exam reference list for the Massachusetts subjects. 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 Massachusetts was $68,550 a year ($32.96 an hour) in 2025, compared with $60,020 nationally. One in ten earned $50,980 or less, and one in ten earned $91,390 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
You can hold a license at any grade you pass; this is the experience the board requires for Full status. Education can replace part of it, up to the limit for each grade: a high school diploma counts as 2 years, an associate's degree in wastewater treatment technology or a listed field, or a bachelor's in another field, as 3, a bachelor's in engineering, environmental science, biology, chemistry, bacteriology or public health as 4, and a master's in a listed field as 5. Short wastewater courses can add 3 to 18 months, as the board decides.
From another state
An operator certified in another state can apply for certification by reciprocity. Your certification must be based on an exam recognized by Massachusetts or ABC, and you must meet Massachusetts's experience requirements.
Send proof you passed a written exam in another state, a resume of your duties and dates at each facility, flow diagrams of each facility, and a copy of that state's certification rules or proof of an accepted reciprocity registry.
Mail the application with an $80 check or money order payable to the Commonwealth of Massachusetts to MassDEP, P.O. Box 4062, Boston, MA 02211. The board will not consider incomplete applications.