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Operators in training wearing yellow vests, eye protection and hard hats at a King County treatment plant. Note: photo was taken prior to Covid mask protocols. 2017 OIT class. Note: photo was taken prior to Covid mask protocols.

APPLY: 2022 Operator in Training (OIT)
Application deadline is March 3, 2022.
Learn more about being an OIT .

Here is what you can expect if you are selected

Program Overview

We are looking to hire 17 Operator in Training (OIT) Program participants into 6-month short term temporary Utility Worker positions. These positions are essential paid on-the-job training positions that can lead to career service employment with King County Wastewater Treatment Division (WTD).

Candidates will start their training at the South Plant, the County’s wastewater treatment plant in Renton, Washington in the sixth OIT Training Academy. Participants will work Monday – Friday, excluding holidays, 8 hours per day. After approximately 3 months in the Academy, the OITs will rotate through multiple Operating teams working both rotating and non-rotating shifts.

After the three (3) month WTD OIT Academy, participants will be rotated to a different OIT position every three months in order to experience all work shifts and Operations at all 3 of the large Wastewater Treatment Plants. These assignments may be Operations day jobs, or rotating shift jobs, which are 6:00 am – 6:00 pm for two days and then 6:00 pm – 6:00 am for two-night shifts. Rotating shift jobs, rotate to different days each week in a 4-days of work and 4- days off work pattern.

These assignments may be located at any of King County Wastewater Treatment Facilities in Renton, Seattle or Snohomish County:

Within 6 months of Wastewater Treatment Training the OIT participants ARE REQUIRED to successfully pass the Washington State Department of Ecology Wastewater Operator in Training Certification exam. Once the participant achieves the State certification, they are eligible to move into the Term Limited Temporary position of an OIT and receive a wage increase.

2022 Hiring Process

  • Applications being taken online from Friday, February 4, 2022, through February 28, 2022.
  • After the job posting closes, applicants will be asked to take an online written qualifying exam.
  • The most successful applicants on the exam will be invited to participate in a hands-on practical exam.
  • The most successful applicants on the practical exam will be invited to an online interview.
  • A WTD hiring team will process the interview scores, and forward a list of the top 17 candidates to the hiring authority for approval.
  • The anticipated start date of the 2022 OIT Academy is Monday, May 16, 2022.


  • Three months of classroom training
  • Wastewater Fundamentals Course work
  • Tours of King County Wastewater Treatment Facilities
  • In-person meetings with various staff from throughout the WTD
  • On the job training with certified wastewater treatment Operators
  • Team building exercises
  • Multiple field trips exploring a variety of facilities involved in wastewater treatment
  • Training on essential Operator skills, including but not limited to:
    • Forklift Driving
    • Defensive Driving
    • Confined Space Training
    • Hazardous Communications
    • Pumps 101
    • Plant hydraulic flows

In the field Job Training and Classroom

  • Technical Trainers Support
  • Supervisor support
  • Co-workers support


  • A well trained, well rounded WWTPO I (certified Washington State Wastewater Operator) within 1 year
  • Potential to obtain a King County Wastewater Career Service Wastewater Operator position
  • A motivated employee with energy, eagerness and who is excited to fill a position that is dedicated to protecting the health of our community and our environment
  • Fill a satisfying role that makes a difference
  • A Union Job providing a family living wage, excellent benefits, including a State sponsored pension for life
  • All in a workplace where supporting diversity and inclusion is the rule


2021 Utility Worker/Operator in Training Program starting wage rate:

2021 Operator in Training (OIT) Program – 6th month, program progression wage rate:

2021 Operator starting wage rate:

KC WTD --- Building Our Future Through Training

West Point Treatment Plant tour

South Treatment Plant tour