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Waterworks operator certification

Municipal waterworks operators work at community water systems that are owned by, or serve, a city, town, village, county or other municipality. Also included in this definition are county or state-owned public institutions for congregate care or correction.

A "certified operator" is an individual who has met the requirements of Chapter NR 114, Wisconsin Administrative Code, and has been issued a certificate by the DNR to operate one or more of the classifications of waterworks treatment plants.

In order to become certified as a waterworks operator, you must pass one or more subclass exams. The exam(s) which you should take is dependent upon the processes at the treatment plant at which you work or would like to work.

Study guides are a valuable tool to help prepare for exams. There are also several courses, listed on our training calendar, that help prepare for exams. Prior education or training is not required before taking the exams, however, some classroom or online training is recommended.


All publicly owned waterworks are required to have a certified operator and are assigned a Grade of 1. Each plant must have a designated operator-in-charge certified in the appropriate subclasses for the processes used at the plant. Class S waterworks facilities must have an operator certified at Grade T or Grade 1 in the Surface Water subclass on duty at all times of operation. Waterworks subclasses correspond to the processes used and are assigned letters as follows:

Subclass Name Description
D Distribution Containing a distribution system
G Groundwater Utilizing a groundwater source
I Iron removal Providing iron removal by oxidation and filtration
L Lime softening Providing treatment by lime–soda ash process for iron removal or softening, or both
S Surface water Utilizing a surface water source
V VOC Providing special treatment such as, but not limited to, air stripping, granular activated carbon or others
Z Zeolite softening Providing zeolite softening or specific contaminant removal by resins.

Grade levels

The requirements for waterworks operator certification for each grade are:

  • Grade T (Operator-in-Training) — Pass waterworks subclass exam(s).
  • Grade 1 — Pass the appropriate subclass exam(s), plus one year of satisfactory experience in the operation of a waterworks plant subclass(es).

Experience is documented on the Waterworks Operator Experience Form (3400-066B) available on the forms page. One year of experience is based on full-time employment at a treatment plant or 1,000 hours of cumulative experience, over a minimum of twelve months, for part–time operators.


If you have a current wastewater and/or waterworks certificate from another state and are interested in applying for reciprocity to Wisconsin's operator certification program, application materials are available on the forms page.

Study guides are a valuable tool to help prepare for the exams; they provide the objectives that are covered on the exams.

Refer to the resources listed at the end of the study guide to look up the answers to each objective. Several resources are available online for free, such as Wisconsin Administrative Codes and EPA documents. Manuals can be purchased online or checked out via inter-library loan through the UW Water Library. You may also check with the facility where you work to see if they have some of the manuals on hand. In addition, you may review these study tips.

Subclass Study Guide Edition Date
D Distribution Revised February 2016
G Groundwater Revised February 2016
I Iron removal January 1994
L Lime softening January 1994
S Surface water Revised February 2016
V VOC removal January 1998
Z Zeolite softening January 1994

Classroom and online training

There are several courses that help prepare for the exams(s). Some of the training providers are:

Please note that this is not a complete list of training options.

Municipal waterworks operators need continuing education to maintain their certifications. This continuing education requirement is designed to help operators keep current on new requirements and technical innovations. Continuing education also helps operators acquire additional knowledge and skills. Continuing ed requirements are based on the renewal cycle for certifications - certification must be renewed every three years.

  • Both Grade T and Grade 1 operators require 18 hours of continuing education.
  • Surface water operators designated as operator–in–charge are required to have 24 hours of continuing education.

Credits must be earned within the three-year certification period. For example: If November 1, 2016, is the expiration date of the certification, continuing education credits must be earned between November 1, 2013, and November 1, 2016, to be valid for renewal.

The continuing education must be relevant towards the operation of a waterworks treatment plant. Continuing education credits may be obtained in a number of different ways including attendance at professional organization meetings or conferences, wastewater related courses (such as those offered at technical schools, colleges, or non–profit organizations), or approved online waterworks courses. Please refer to our training web page for an extensive list of applicable courses and events.

Credit for courses or training is determined by the following criteria:

  1. Each hour spent in course learning constitutes one credit hour of continuing education credit (minus time spent for registration, breaks and lunch).
  2. A maximum of six hours health and safety related training may be used per renewal period. Examples of health and safety related training include first aid/CPR, confined space entry, excavation safety, personal protective equipment, Hazwoper, RCRA, and bloodborne pathogens.

If an operator takes a training that was not pre-approved, but is relevant towards waterworks operations, the operator may complete the Operator Training Report Form (4400–190) available on the training web page to document the training.

Operator certifications come up for renewal every three years. The operator certification program sends courtesy renewal reminder letters to operators six weeks before their certification expiration date. It is important for operators to keep their address current by notifying their regional coordinator of any changes. The letter serves as a courtesy reminder only; it is the operator's responsibility to keep track of their certification expiration date. When the operator is ready to renew, they should mail in the courtesy reminder letter, their continuing education documentation, and the $45 renewal fee to:

Wisconsin DNR
Operator Certification Program — EAS/7
PO Box 7921
Madison WI 53707-7921

The renewal materials must be postmarked by the expiration date on the certificate (there is no grace period). Any renewal postmarked after the expiration date should also include the $25 late penalty fee.

Once a certification expires, an operator has one year from their expiration date to reinstate their lapsed certification. An operator is not considered a certified operator during this lapse of certification. If a certification is not renewed within that one-year time period, the operator will need to re-take the exams as a new operator.


Where can I obtain the application to take an exam?
Applications are available on the exams web page in mid-February for the May exam day and in mid-August for the November exam day.
How much does it cost to take an exam?
Each exam is $25. Exam fees are non-refundable.
When will I be notified of my exam results?
Exam results letters are sent within 30 days after the exam day. A list of missed objectives is printed on the exam results letter, which help an operator determine which areas of the study guide to focus on.
I passed the exams and have hands-on experience. Why is my certification still Grade T?
To upgrade to Grade 1, you need to document your experience on the Waterworks Operator Certification Experience Form. You must have at least a year of hands-on experience to upgrade to Grade 1. Experience forms should be mailed to your regional coordinator (refer to Contacts tab). If approved, you will receive a new certificate in the mail reflecting the upgrade.
What classes can I take to get continuing education credits?
Check our training calendar for a current list of training opportunities, as well as a list of online training providers.
When should I submit my continuing education documentation?
Keep your credit slips and other documentation on file. Courtesy renewal reminder letters are mailed six weeks prior to your expiration date, provided that we have a current address for you on file. At that time, mail in your reminder letter, continuing education documentation, and the appropriate fee before the expiration date on your certificate.
What if I earn more credits than I need?
That's great!! Those credits become a part of your record. However, credits cannot be carried over to the next renewal period. They must be earned within your license period printed on your certificate.
What if I don't have enough credits to renew?
Send in the required continuing education documentation when you have accumulated enough credits and a $70 fee ($45 renewal fee and $25 penalty fee) to the department to get your certification renewed. You have one year after the expiration of your certificate to renew. If you do not renew your certification within that one-year period, your operator record will be deleted, and you will have to retake all exams.
I took a class a few days prior to my certification expiration date, and it is not showing up yet on my training history report. What do I need to do to renew my certification on time?
Print your Training History Report and hand–write in the missing class. Mail in your renewal. Once the DNR Operator Certification Program receives the attendance roster from the training provider, we will verify your attendance.

"The Certified Operator" is the annual newsletter of the operator certification program distributed annually to all certified wastewater and municipal waterworks operators. The newsletter highlights program information and updates. This newsletter is emailed to operators who have an email address on file. Operators that request hard copies will receive the newsletter via regular mail.

Previous editions of "The Certified Operator"

Contact your regional coordinator for any questions regarding your certification. Experience forms should be mailed to your regional coordinator.

If no regional coordinator is listed, send questions and the wastewater experience form to the Statewide Coordinator (contact information listed below).

Printer-friendly list of waterworks coordinators

Regional coordinators

Regional office Coordinator name Counties of responsibility
DNR — South Central Region
3911 Fish Hatchery Rd
Fitchburg WI 53711
Sarah Graves Graber
Columbia, Crawford, Dane, Dodge, Grant, Green, Iowa, Jefferson, Lafayette, Richland, Rock, Sauk
DNR — Southeast Region
1155 Pilgrim Rd
Plymouth WI 53073
Stephanie Pfeiffer
Kenosha, Milwaukee, Ozaukee, Racine, Sheboygan, Walworth, Washington, Waukesha
DNR — Northeast Region
2984 Shawano Ave
Green Bay WI 54313-6727
Heather Hermes
Brown, Calumet, Door, Fond du Lac, Green Lake, Kewaunee, Manitowoc, Marinette, Marquette, Menomonie, Oconto, Outagamie, Shawano, Waupaca, Waushara, Winnebago
DNR — West Central Region
1300 W Clairemont Ave
Eau Claire WI 54701
Pat Radle
Adams, Buffalo, Chippewa, Clark, Dunn, Eau Claire, Jackson, Juneau, La Crosse, Marathon, Monroe, Pepin, Pierce, Portage, St. Croix, Trempealeau, Vernon, Wood
DNR — Northern Region
810 Maple St
Spooner WI 54801
Sarah Graves Graber
Ashland, Barron, Bayfield, Burnett, Douglas, Florence, Forest, Iron, Langlade, Lincoln, Oneida, Polk, Price, Rusk, Sawyer, Taylor, Vilas, Washburn

Statewide Coordinator

PO Box 7921, EA/7
Madison WI 53707–7921

Program Assistant

Jordan Schutz
Phone: 608–228-5190

For general questions, contact