Wastewater Treatment Operator

Under general supervision, operates, inspects, and maintains a variety of plant equipment in connection with the continuous operation of a large metropolitan wastewater treatment plant; directs lower level operators; and performs related work as required.

Example Knowledge, Skills, and Abilities Working knowledge of:

The operation, maintenance and cleaning of primary and secondary wastewater treatment equipment and facilities; wastewater treatment principles, methods, and practices; arithmetic; safety rules, codes, and regulations pertaining to the work; basic first aid; the methods and precautions in storing and handling chlorine and other hazardous gases and chemicals; wastewater sampling and routine process control tests.

General knowledge of:  Routine facility and equipment maintenance and cleaning methods.

Skill in:  Operating wastewater treatment plant equipment, including automatic control devices performing routine maintenance and making operating adjustments to wastewater treatment equipment; cleaning and painting facilities and equipment; operating assigned plant equipment without immediate or detailed supervision.

Ability to:  Recognize unusual, inefficient, or dangerous operating conditions and take appropriate action; accurately read and record data from gauges and meters; instruct and direct the work of lower level employees; interpret plant, piping, and distribution diagrams; perform routine control tests and adjust plant equipment accordingly; keep records and make oral and written reports of work performed; and establish and maintain effective working relationships.

Example Experience and Training

Four years journey-level Operator and/or Stationary Engineer experience in the maintenance, repair and operation of a variety of mechanical and electrical pumping and related plant machinery of a water or wastewater treatment plant; or four years journey-level experience as a Marine Engineer performing duties in the areas of maintenance, repair and operation of a variety of mechanical and electrical pumping and related machinery; or completion of a recognized four year Stationary Engineer apprenticeship program.

Special Requirements: Must possess physical characteristics to perform the critical and important duties of the class.  Must be clean shaven at all times as required to wear respiratory protection equipment.  Must have sufficient strength to lift sacks of chemicals weighing up to 50 pounds.  Must be willing to work with and around chemicals used in the wastewater treatment process.  Must be willing to work shifts, weekends, holidays, and overtime as needed.  Must be willing to work outdoors in a variety of weather conditions.

Wastewater treatment operator certification levels

Effective April 1, 2013. Note: Applicants must take and pass the Office of Operator Certification Wastewater Treatment Plant Operator Examination before applying for Certification:

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To work in a public wastewater treatment plant or a private wastewater treatment plant regulated by the PUC, you must have a valid wastewater treatment plant operator certificate or an operator-in-training certificate. There are three major things that you must do to get certified:

  1. You must take courses in wastewater treatment plant operations. The number and difficulty depend on the certificate grade you want. Specialized training courses can be obtained from a community college or correspondence courses through the Office of Water Programs at the California State University, Sacramento
  2. You must pass a written exam. Wastewater treatment plant operator certification exams are given twice each year, once in early April and once in early October. Exas for all five grades are given at the same time at several locations throughout the state. To take an exam, you must show that you meet the minimum educational requirements and submit a fee and application.
  3. You must meet experience requirements and submit a fee and an application for a certificate. Your experience must be in the operation of a wastewater treatment plant with a valid operator certificate or operator-in-training certificate. You may submit your application for a certificate up to four years after you pass the written exam.
    If you have no experience as an operator, you must get an Operator-in-Training (OIT) Certificate. The owners of the plant do the hiring of operators, usually a city, county or special district. You need to contact them to see if there are any jobs available. Other potential sources of job listings are local newspapers local sections of the California Water Environment Association.


Example ANNUAL Salary

  • Apprentice/Trainee $56-70,000
  • Journey-level $73-90,000
  • Supervisory $100-125,000

Source: BAYWORK Salary Survey, 2014 (updated in 2017 for inflation)