On-Site Designers and Inspectors Exams

Exam Information

The On-Site Wastewater Treatment Systems Designer exam is a multiple choice, 4-hour, open book exam.  The state exam is offered twice a year in Western and Eastern Washington. 

Materials must be bound, such as a three-ring-binder, no loose-leaf paper allowed. Calculators are allowed but must follow the NCEES Calculator Policy.

Examination date

Application and reschedule deadline

March 22, 2024

Application and reschedule deadline February 23, 2024

September 20, 2024

Application and reschedule deadline August 23, 2024

** If you do not receive a response from the board office within 2-weeks of submittal, please contact the board office at engineers@brpels.wa.gov or 360-664-1575.

Exam blueprint

See the Washington State On-Site Designer/Inspector Blueprint.

How to Reschedule an Exam

Complete the reschedule application and submit online or by mail.

To reschedule online, login to your account, access our service “Manage Existing Professional License or Exam Application”

  1. Click the Submitted Requests tab
  2. Click your application number
  3. Click the Reschedule Exam in the blue menu bar

After You Pass the Exams

The state exam results are reviewed by the board for final approval. Board meeting information can be found here.

Make sure that we have your current mailing and email address.

If you have passed both the NCEES 6-hr exam and the state 4-hr exam you will receive an electronic copy of your license by email, a hard copy will arrive in 7-10 business days and the wall certificate will arrive in 8 – 10 weeks.