WASTEWATER TREATMENT PLANT OPERATOR
County of Los Angeles, CA - Los Angeles, CA
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Salary : $105,975.84 AnnuallyLocation : Los Angeles County, CAJob Type: Full timeJob Number: C7224HDepartment: PUBLIC WORKSOpening Date: 02/18/2026 Position/Program InformationEXAM NUMBERC7224HFILING PERIOD 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.TYPE OF RECRUITMENTWe welcome applications from everyone. Why work for us?With more than 10 million residents, Los Angeles County has the largest population of any county in the nation! As the largest employer in Southern California, with more than 42 diverse departments and over 2,300 different job descriptions, the County offers a lifetime of opportunities and careers. We are Los Angeles County Public Works, the largest municipal public works agency in the nation. With more than 4,000 employees, Los Angeles County Public Works offers over 500 different types of career opportunities that promote professional and personal growth as well as a rewarding and exciting work environment!For more information about the outstanding benefits offered by Los Angeles County, please visit us here: 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: Essential Job FunctionsA 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. RequirementsREQUIREMENTS 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. If you are unable to attach required documents with your application, please e-mail within five (5) business days from the date of filing the application. Include your name, exam number, and exam title in the Subject line of your e-mail. 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 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 InformationEXAMINATION CONTENT:This examination will consist of TWO (2) parts: Part I: Multiple choice and/or simulation assessment(s), weighted at 60%, assessing:ThoroughnessMechanical ComprehensionAchievementSafety OrientationResponsibilityTeamworkDeductive ReasoningMULTIPLE 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 PlantsMechanical ComprehensionSafety FocusProblem SolvingApplicants 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 . The section dedicated to test preparation is "Employment Test Assistance." * Online practice tests are available at .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.We will send notifications to the email address provided on the application, so it is important that you provide a valid email address. If you choose to unsubscribe or opt out from receiving our emails, it is possible to view notices by logging into and checking the profile inbox. It is every applicant's responsibility to take steps to view correspondence, and we will not consider claims of missing notices to be a valid reason for re-scheduling an exam part. Register the below domains as approved senders to prevent email notifications from being filtered as spam/junk mail.New email addresses need to be verified. This only needs to be done once per email address and can be done at any time by logging in to and following the prompts. This is to enhance the security of the online application and to prevent incorrectly entered email addresses.SOCIAL SECURITY NUMBER: Federal law requires that all employed persons have a Social Security Number, so include yours when applying.COMPUTER AND INTERNET ACCESS AT PUBLIC LIBRARIES: For candidates who may not have regular access to a computer or the internet, applications can be completed on computers at public libraries throughout Los Angeles County.NO SHARING OF USER ID, E-MAIL, AND PASSWORD: All applicants must file their application using their own user ID and password. Using a family member or friend's user ID and password may erase a candidate's original application record.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:Department Contact Name: Annette WeaverDepartment Contact Phone: (626) 458-2141Department Contact Email: Coordinator Phone: (626) 458-2141Teletype Phone: (626) 282-7829California Relay Services: (800) 735-2922COUNTY OF LOS ANGELES Employment InformationAny language contained in the job posting supersedes any language contained below.This document is intended to provide general information about the recruitment process of the County of Los Angeles. Applicants with questions about a specific job posting should contact the exam analyst listed on the posting.Equal Employment Opportunity/Non-Discrimination Statement:The County of Los Angeles is an Equal Employment Opportunity Employer and is committed to non-discrimination in the County workforce, regardless of age (40 and over); ancestry; color; ethnicity; religious creed; protected family or medical leave status; disability; marital status; medical condition; genetic information; military and veteran status; national origin; race ; sex; gender; sexual orientation; or any other characteristic protected by State or federal law. For more information, please visit: Testing Accommodations for Applicants:The County of Los Angeles complies with all federal and state disability laws and makes reasonable accommodations for qualified applicants and employees with disabilities. If a reasonable accommodation is needed to participate in the job application process, please contact the testing accommodation coordinator listed on the job posting. Hearing impaired applicants with telephone teletype equipment may leave messages by calling the teletype phone number on the job posting. For more information on accommodations, please visit: Fair Chance:The County of Los Angeles is a Fair Chance employer. Except as otherwise permissible under applicable laws, you will not be asked to provide information about conviction history unless you receive a conditional offer of employment. The County will make an individualized assessment of whether your conviction history has a direct and adverse relationship with the specific duties of the job, and will also consider potential mitigating factors, which may include, but is not limited to, evidence and extent of rehabilitation, recency of the offense(s), and age at the time of the offense(s). If asked to provide information about conviction history, any convictions or court records which are exempted by a valid court order do not have to be disclosed. Qualified applicants with arrest or conviction records will be considered for employment in accordance with County Fair Chance Policies and the Fair Chance Act (Gov. Code Section 12952).Employment Eligibility:Final appointment is contingent upon verification of U.S. citizenship or the right to work in the United States.Career PathFinder:Resources to help current and prospective employees plan a career with Los Angeles County are available. To explore career paths to and from nearly all job titles, please visit our interactive Career PathFinder application at Veteran's Credit:Pursuant to the County Charter and County policy, in all open competitive examinations (i.e., examinations open to everyone), the County of Los Angeles will add a credit of 10 percent of the total credits specified for such examination to the final passing score of an honorably discharged veteran, as well as the spouse of a deceased or disabled veteran, who served in the Armed Forces of the United States under specific conditions.For more information on veteran's credit, please visit: Revised September 2025For detailed information, please click 01 All-important notifications including invitation letters will be sent electronically to the email address provided on the application. It is important that you provide a valid email address. DO NOT select "off" under Email Preferences within your profile or click "unsubscribe" on our notices if you would like the County of Los Angeles to notify you regarding your application status, test schedules, and other important information pertaining to your candidacy for this position.Please add the following emails to your email address and list of approved senders to prevent email notifications from being filtered as spam/junk/clutter mail. @pw.lacounty.govinfo@talentcentral@noreply@donot-reply@It is your responsibility to take the above steps to view correspondence. Los Angeles County will not consider claims of not viewing or receiving notification to be a valid reason for late test administration or rescheduling of a test compensation or rescheduling of an exam component. I understand the above information and instructions. 02 Applicants have the ability to opt out of emails from Los Angeles County. If you unsubscribe, you will not receive email notifications for any examination for which you apply with Los Angeles County. If you choose to unsubscribe, you can check for notifications by logging into to view your profile inbox. Exam scores cannot be disclosed over the phone. I understand the above information and instructions. 03 The information you provide on this supplemental questionnaire will be evaluated and used to determine your eligibility to participate in the next phase of the examination process. Please be as specific as possible. Comments such as "see resume or application" will not be considered as a response. Please note that all information is subject to verification at any time in the examination and hiring process. Falsification of any information may result in disqualification or dismissal. I understand the above information and instructions. 04 Do you have a valid Wastewater Treatment Plant Operator's Certificate, Grade II or higher*, issued by the California State Water Resources Control Board?* Applicant 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. Applications submitted without the required certificate will be rejected as incomplete. Registration will be subject to verification before being appointed. Yes, and I have attached a copy to my application. Yes, and I will email a copy to within (5) business days from the date of filing the application. No, I do not possess a valid Wastewater Treatment Plant Operator's Certificate, Grade II or higher, issued by the California State Water Resources Control Board. 05 If you indicated "yes" to Question #4, please include the following:Certificate No:Last Name:First Name:Grade Level:Issued Date:Expiration Date:If you do not have a certificate under this option, please write "DOES NOT APPLY" 06 TRAINING & EXPERIENCE EVALUATIONWastewater Treatment Plant Operator General Information: This Training & Experience (T&E) Questionnaire is a self-assessment. You will respond to questions about your experience related to having acquired the knowledge, skills, and abilities to successfully perform the Wastewater Treatment Plant Operator position. All information that you provide is subject to verification. The assessment will evaluate the following competencies:1. Professional/Technical Knowledge of the Operation & Maintenance of Sewage Treatment Plants2. Mechanical Comprehension 3. Safety Focus4. Problem Solving This assessment is weighted 40%. All completed questionnaires will be scored according to standardized criteria.Instructions for CompletionCarefully read the official County job bulletin for this examination.You will receive points for each question based on the response(s) you provide. You will receive zero points for any question on which you do not provide a response.Certification StatementBy completing the following, I hereby attest that all information I have provided in this T&E Questionnaire is true and complete to the best of my knowledge. I acknowledge that Human Resources staff may contact my supervisor(s) to verify the information that I have provided. I understand that any misrepresentations, falsifications, or omissions of material facts violates Civil Service Rules and may subject me to actions including removal from this examination.Furthermore, I certify that I will not disclose the questions used in this examination to any candidate nor will I provide any information to anyone concerning anything related to the questions posed to me other than concerned parties in an official protest or appeal. I understand that violation of this agreement can result in my disqualification from this examination as provided by Civil Service Rules. YES 07 Please indicate the highest grade of Wastewater Treatment Plant Operator Certificate you currently hold, as issued by the California State Water Resources Control Board (SWRCB): Wastewater Treatment Plant Operator Certificate, Grade II Wastewater Treatment Plant Operator Certificate, Grade III Wastewater Treatment Plant Operator Certificate, Grade IV Wastewater Treatment Plant Operator Certificate, Grade V None of the above 08 Did you attach a legible copy of your active certificate(s) to your application? (If you did not, supporting documentation must be e-mailed to within five (5) business days of filing your application.) 09 Describe your highest level of involvement in monitoring and adjusting wastewater treatment processes (e.g., aeration, sedimentation, disinfection). I have observed these processes but did not make adjustments. I have monitored and reported readings or test results to others for adjustment. I have independently adjusted treatment processes based on test results and system performance. I have made operational decisions and provided guidance to others on process control and adjustments. I have no experience. 10 In order to receive credit for the previous question, please provide a description of your involvement in monitoring and adjusting wastewater treatment processes. Include your: Position title Employer Immediate supervisor name(s) Phone number Approximate dates of your experiences: From (mm/dd/yr) - To (mm/dd/yr) If you have no experience in this area, then indicate "N/A." Comments such as "see resume or application" will not be considered as a response. Failure to provide a response may result in no or partial credit. 11 Select the statement that best describes your experience providing guidance, instruction, or training to others in a wastewater treatment setting. I have assisted coworkers by explaining procedures or demonstrating tasks. I have trained or coached new operators or staff on treatment processes or safety procedures. I have supervised or directed the daily work of other operators or assigned personnel. I have not provided guidance or training to others. 12 In order to receive credit for the previous question, please provide a description of your experience providing guidance, instruction, or training to others in a wastewater treatment setting. Include your: Position title Employer Immediate supervisor name(s) Phone number Approximate dates of your experiences: From (mm/dd/yr) - To (mm/dd/yr) If you have no experience in this area, then indicate "N/A." Comments such as "see resume or application" will not be considered as a response. Failure to provide a response may result in no or partial credit. 13 Indicate which types of wastewater treatment processes or systems you have regularly monitored and adjusted as part of your work duties. (Select all that apply.) Activated sludge processes with secondary clarification MBR (Membrane Biological Reactor) Coagulation and flocculation systems Filtration systems Disinfection systems (e.g., UV, chlorination) SCADA-based systems for flow, quality, or pressure control Solids handling None of the above 14 In order to receive credit for the previous question, please provide a specific experience with EACH type of wastewater treatment process or system selected. Include your: Position title Employer Immediate supervisor name(s) Phone number Approximate dates of your experiences: From (mm/dd/yr) - To (mm/dd/yr) If you have no experience in this area, then indicate "N/A." Comments such as "see resume or application" will not be considered as a response. Failure to provide a response may result in no or partial credit. 15 Which of the following repair or diagnostic activities have you performed in the course of your work duties? (Select all that apply.) Troubleshoot equipment malfunctions within the treatment plant by using diagnostic tools, manuals, and hand tools Maintained or calibrated flow meters, analyzers, or chemical feed systems Performed preventive maintenance (e.g., lubricating, replacing filters, adjusting equipment) Performed minor mechanical repairs (e.g., replaced valves, seals, or other mechanical parts) Assisted in major repairs or rebuilds of large-scale treatment equipment Coordinated or directed contractors or maintenance crews for major repairs None of the above 16 In order to receive credit for the previous question, please provide a specific experience with EACH type of repair or diagnostic activity selected. Include your: Position title Employer Immediate supervisor name(s) Phone number Approximate dates of your experiences: From (mm/dd/yr) - To (mm/dd/yr) If you have no experience in this area, then indicate "N/A." Comments such as "see resume or application" will not be considered as a response. Failure to provide a response may result in no or partial credit. 17 Which statement best describes your highest level of involvement in collecting, conducting, and interpreting laboratory tests on influent, process samples, or effluent? I collected and labeled samples for testing by others but did not perform tests myself. I performed basic field tests (e.g., pH, chlorine residual, dissolved oxygen) and recorded results for review by others. I performed basic field tests (e.g., pH, chlorine residual, dissolved oxygen) and used results to recommend or make process adjustments. I operated laboratory equipment to conduct standard wastewater analyses and used results to recommend or make process adjustments. No experience 18 In order to receive credit for the previous question, please provide a description of your involvement in collecting, conducting, and interpreting laboratory tests on influent, process samples, or effluent. Include your: Position title Employer Immediate supervisor name(s) Phone number Approximate dates of your experiences: From (mm/dd/yr) - To (mm/dd/yr) If you have no experience in this area, then indicate "N/A." Comments such as "see resume or application" will not be considered as a response. Failure to provide a response may result in no or partial credit. Required Question
Created: 2026-04-02