Certified Treatment Designer - CTD

The Certified Treatment Designer is a brand-new certification title from WQA. Designed for people who work in business-to-business sales and support, a CTD seal assures dealers of getting knowledgeable technical support. 

Who is it for?

  • Business-to-Business technical sales and support
  • Research and Design Engineers
  • Public Health Professionals
  • Commercial/industrial water system operators involved in troubleshooting and maintenance

What are the training goals?

  • Knowledge of drinking water regulations
  • A focus on properly identifying water contaminants
  • Appropriate treatment solution selection​
  • Correctly sized equipment
  • Knowledge of product certification standards
  • Documented practical experience
  • An emphasis on ethical business practices



  • Five years experience AND
  • Pass exam**

Note: Must register for exam no less than 90 days prior to the intended exam date. A completed CTD exam application and a current resume or CV demonstrating the appropriate experience is required.

* The exam assumes a level of proficiency that draws on both field experience and basic knowledge of point-of-use/point-of-entry water treatment. Completion of WQA’s training courses does not guarantee success on the exam.​ Please refer to the exam blueprint in the CTD Candidate Handbook for more information on the exam content.

**Retakes are allowed; 6 month waiting period and full exam fee required


  • Certification is valid for three years
  • 30 hours (3.0 CPD) continuing education is required
  • Recertification fee

Advantages of WQA Professional Certification

  • Credibility
  • Market differentiation
  • Employee engagement & retention
  • Companies with certified personnel are indicated in WQA's Treatment Provider directory.

Frequently Asked Questions

Q: How long does the training take?

A: The training is self-paced. The learner is given one year to complete the training, but most people who are employed full time can complete the training in six to nine months.

Q: Do I need a mentor?

A: The Water Treatment Design training does NOT require a mentor.

Q: How should I prepare for the exam?

A: The exam requires knowledge of a broad range of POU/POE water treatment applications and treatment technologies. Examinees should be familiar with problem water contaminants, treatment of aesthetic and drinking water problems, product certification, and treatment equipment operations and troubleshooting. The Water Treatment Design course provides excellent training on these topics and WQA members can also use the Knowledge Base for review. See the exam blueprint for additional information on the exam topics.

Get started!

Enroll in the Water Treatment Design course

Register for the Certified Treatment Designer Exam