WASTEWATER TREATMENT PLANT OPERATOR

Full Job Description

The application filing period will begin on February 19, 2026, at 8:00 a.m. (PT) – Continuous. We will keep accepting applications until the position is filled. The application window may close unexpectedly once we have enough qualified candidates.

Why work for us?

For more information about the outstanding benefits offered by Los Angeles County, please visit us here: https://hr.lacounty.gov/benefits/.

If you have questions about working for Los Angeles County, including current open recruitments, tips on crafting a resume or acing an interview, career planning, or any other general information, please visit our website at: https://hr.lacounty.gov/.

Requirements

A Wastewater Treatment Plant Operator is responsible for performing a combination of the following essential job functions:

• Inspects, operates, and maintains sewage pumps, flow metering stations, extended aeration and activated sludge processes, clarifiers, filters, disinfection systems, chemical feed systems, digesters, monitoring devices, centrifuges, effluent disposal and irrigation systems, and other related equipment used to treat raw sewage;
  
• Monitors and checks operational parameters of physical, chemical and biological processes that clean wastewater and makes process adjustments to optimize operating parameters and achieve effluent quality standards;
  
• Isolates causes of plant malfunctions, makes necessary adjustments and minor repairs to equipment and orders major repairs;
• Collects water samples from groundwater wells, surface waters, and treatment plants at various process stages;
• Performs routine process control and regulatory laboratory tests of water samples;
• Maintains plant, equipment, and test records for evaluation of plant operating performance, preventive maintenance and preparation of regulatory reports;
• Obtains quotes for supplies, chemicals, and replacement parts;
• Lifts, stores, and dispenses liquid and solid chlorine, and other chemicals at treatment plant sites;
• Performs general maintenance of facility grounds and buildings including safety inspections, and ensures compliance with facility Best Management Practices;
• Drives automotive equipment to and from work sites.

Qualifications

REQUIREMENTS TO QUALIFY:

A valid Wastewater Treatment Plant Operator's Certificate, Grade II or higher*, issued by the California State Water Resources Control Board.

LICENSE:

A valid California Class C Driver License is required at the time of appointment to perform job-related essential functions.

Successful applicants for positions that require driving must obtain and present a copy of their driving record from the California State Department of Motor Vehicles before final appointment.

Applicants should not present a copy of their driving history until asked to do so by the hiring department.

The County will make an individualized assessment of whether an applicant’s driving history has a direct or adverse relationship with the specific duties of the job.

License must not be currently suspended, restricted, or revoked.

PHYSICAL CLASS:
Physical Class III – Moderate: Includes standing or walking most of the time, with bending, stooping, squatting, twisting, and reaching; includes working on irregular surfaces, occasionally lifting objects weighing over 25 pounds, and frequent lifting of 10-25 pounds.

SPECIAL REQUIREMENT INFORMATION:

*APPLICANTS MUST PROVIDE A COPY OF THEIR VALID WASTEWATER TREATMENT PLANT OPERATOR'S CERTIFICATE, GRADE II OR HIGHER, ISSUED BY THE CALIFORNIA STATE WATER RESOURCES CONTROL BOARD AT THE TIME OF FILING OR WITHIN FIVE (5) BUSINESS DAYS FROM THE DATE OF FILING THE APPLICATION. THE COPY OF THE WASTEWATER TREATMENT PLANT OPERATOR CERTIFICATE PROVIDED MUST SHOW THE DATE OF EXPIRATION. A PRINTOUT WITH EXPIRATION DATE FROM THE STATE WATER RESOURCES CONTROL BOARD WEBSITE WILL BE ACCEPTED. REGISTRATION WILL BE SUBJECT TO VERIFICATION BEFORE BEING APPOINTED.
We do not accept password-protected documents. Ensure documents are unlocked before attaching to your application or sending to the exam analyst.

If you are a veteran, you may be eligible for veteran’s credit, which is an additional 10% of the total points added to a passing score. We will need a copy of your form DD214 to review, so please include that with your application or email it to the exam analyst at PWExams@pw.lacounty.gov with the subject of "Wastewater Treatment Plant Operator C7224H" as soon as possible so, if you are eligible for veteran’s credit, we can include it before the list is available.

Additional Information

EXAMINATION CONTENT:

This examination will consist of TWO (2) parts:

Part I: Multiple choice and/or simulation assessment(s), weighted at 60%, assessing:

• Thoroughness
• Mechanical Comprehension
• Achievement
• Safety Orientation
• Responsibility
• Teamwork
• Deductive Reasoning

MULTIPLE CHOICE AND/OR SIMULATION ASSESSMENT(S) ARE NOT REVIEWABLE BY CANDIDATES PER CIVIL SERVICE RULE 7.19.

Part II: An evaluation of Training and Experience, weighted at 40%, assessing:

• Professional/Technical Knowledge of the Operation & Maintenance of Sewage Treatment Plants
• Mechanical Comprehension
• Safety Focus
• Problem Solving

Applicants must meet the Requirements and achieve 70% or higher on the combined score of Parts I and II in order to be placed on the eligible list.

TESTING ACCOMMODATION:

If you require an accommodation to fairly compete in any part of the assessment process, you will be given the opportunity to make a request when completing your application.

Please note, you may be required to submit documentation from a qualified medical provider or other qualified professional to support your request for a testing accommodation.

TRANSFER OF TEST COMPONENTS:
If you have taken identical components recently for other exams, your responses may be automatically transferred to this examination. This exam contains test components that might be used on future exams, and your responses could be transferred to that exam.

SCORES CANNOT BE GIVEN OVER THE TELEPHONE.

TEST PREPARATION:
We provide study guides and other test preparation resources to help candidates prepare for employment tests. While the guides may help in preparing for the test, we recommend reviewing all related materials that seem necessary.

* Various information can be found on our website at https://hr.lacounty.gov/job-search-toolkit/. The section dedicated to test preparation is "Employment Test Assistance."

* Online practice tests are available at https://www.shldirect.com/en-us/practice-tests.

ELIGIBILITY AND VACANCY INFORMATION:
Applicants who passed the assessment(s) are placed on a list in the order of their score group for a period of twelve (12) months. Applications will be processed as they are received and added to the list accordingly. We will use this list to fill vacancies in the Public Works as they occur.

NO PERSON MAY COMPETE FOR THIS EXAMINATION MORE THAN ONCE EVERY TWELVE (12) MONTHS.

APPLICATION AND FILING INFORMATION:

We only accept applications filed online. Applications submitted by U.S. mail, fax, or in person are not accepted. Apply online by clicking on the "Apply" green button at the top right of this posting. This website can also be used to get application status updates.

Please fill out the application completely. Provide relevant job experience including employer's name and address, job title, beginning and ending dates, number of hours worked per week, and description of work performed.

We may verify information included in the application at any point during the examination and hiring process, including after an appointment has been made.

Falsification of information could result in refusal of application or rescission of appointment.

Copying verbiage from the Requirements or class specification as your work experience will not be sufficient to demonstrate meeting the requirements.

Doing so may result in an incomplete application and may lead to disqualification.

• AWeaver@pw.lacounty.gov
• PWExams@pw.lacounty.gov
• klent@hr.lacounty.gov
• info@governmentjobs.com
• talentcentral@shl.com
• noreply@proctoru.com
• donot-reply@amcatmail.com

SOCIAL SECURITY NUMBER: Federal law requires that all employed persons have a Social Security Number, so include yours when applying.

ANTI-RACISM, DIVERSITY, AND INCLUSION (ARDI): The County of Los Angeles recognizes and affirms that all people are created equal and are entitled to all rights afforded by the Constitution of the United States.

We are committed to promoting Anti-racism, Diversity, and Inclusion efforts to address the inequalities and disparities amongst races.

We support the ARDI Strategic Plan and its goals by improving equality, diversity, and inclusion in recruitment, selection, and employment practices.

CONTACT INFORMATION: