How to Become a Licensed Operator and Advance within the Operator Profession

Levels of Water Operator Licenses

Water systems are defined through a process of grading points, Class I to IV in both treatment and distribution categories according to complexity and population served. See Appendix A of the Rules. Operators of these systems must show competency by successfully completing examinations in both treatment and distribution categories and possess the appropriate experience. Very Small Water Systems (VSWS) operators are another classification that covers both treatment and distribution characteristics of systems with less than a population of 500.

Guidance on Becoming a VSWS Operator

Characteristics of a Water Operator

An operator must possess the knowledge, skills, ability and judgment to assure safe drinking water. This is measured through a review of education, experience and examination.

Education & Experience

Operators must have a high school diploma or GED. Experience is based on work in a public water system as well as credit for related professions. The Board offers Operator – In - Training (OIT) license status for persons that have successfully passed examinations but have not achieved the required experience. Holding an OIT license shows employers or prospective employers your capability and interest in the profession.

Operator Experience Requirements
License Experience Required
Very Small Water System Six months
Class I One year
Class II Two years
Class III Three years
Class IV Four years

Board Policy for Evaluating Experience to Qualify for Level of Operator Licenses


Examinations are standardized exams produced by ABC, Association of Boards of Certification. These exams are nationally based, multiple choice, validated and reviewed. The Board welcomes operators to become subject matter experts and participate in the exam development process.

Exams may be taken in the traditional paper-based process or the recently accepted computer-based process. Exams may be taken in the sequential process (pass lower levels and work one’s way up) or may be taken in a direct process (take one exam at the level one wishes licensure).

Computer Based Exams

Applied Measurements Professionals, AMP, now offers Water Operator Exams for Maine licensure, in Portland and Holden, Maine. Maine exams may be taken at any AMP location nationwide.

Exam Prices are $75 for VSWS and $93 for Class I- IV Treatment and Distribution

You may sign up on line or through the mail directly with AMP. Applications through the mail will take longer but can be done with the use of this application form and by calling AMP at (800) 345-6559.

To register on-line Online go to Most questions you may have concerning computerized testing can be answered on this site, but help is available from Doris at 287-5699 or Terry at 287-7485. It is very important to read the Candidate Handbook.

To sign up choose “Candidates

Select a category > Water/Wastewater

Select a program > Maine Board of Licensure of Water System Operators

Select an examination > you may select one at a time or multiple exams, however you must schedule each exam separately.

The Application form is only necessary if paying other than by credit card. The same questions will be asked in the Log-In process

You will be asked to create a Log In – think about this, make sure you can remember your user name and password.

This will have your contact information and will create a page for you to return to on later visits. Once you have created a Log In you will be able to go directly to your page. It will remember what exam you wish to take.

Scheduling an examination Once you have a My Home page you will be able to schedule your test. Click on the Schedule box, select an Assessment Center – in Maine we presently have one site in Portland at the H& R Block 125 Auburn St. Directions are available by clicking the “Locate Testing Centers” box. You may take the test at any AMP testing site.

Check out - Select a day; the fee, time selection and payment information will appear and payment and scheduling will take place.

Please call with any questions or comments you may have. The Board is committed to assuring the examination process is as secure as possible while improving exam availability for operators.

Frequently Asked Questions about the computer-based process

Paper Exams

Paper Exams for the calendar year 2013 were held in April.
The fee for a paper exam is $95 and is non-refundable.
Applications must be received 6 weeks prior to test date, results take 4-6 weeks.
New Exam Application - Old forms will not be accepted.
For more information or to discuss paper exam options please contact Teresa Trott, 287-7485.

Study Materials

ABC offers information to examinees to assist in preparation. There is also a Very Small Water System (VSWS) Study Booklet (pdf) available to help in preparing for Very Small Water System (VSWS) exams.

The DWP maintains a lending library with study materials to help persons prepare for operator exams. Materials may be signed out of the library prior to an exam and returned the day of the exam or mailed back to the DWP after the exam.

Training providers may be found here. Classes may be found in the Professional Development Calendar.

Once you have passed the exam you may apply for licensure.

Initial License or Upgraded License

Your first license is the initial license. This may be a license in one or both treatment and distribution disciplines. When you take and pass a higher level of exam you may apply for an upgraded license.

Click here to open the Application for Licensure


Water operators certified or licensed by other state or provincial certification authorities most often are recognized. Each person’s education and experience is evaluated. Licenses or certificates from states with similar examination requirements may not require re-examination. Please use the application for licensure.