We Are WPI:
We ensure the expertise of water and wastewater treatment professionals through testing and certification.
Water and wastewater treatment professionals are on the front lines of protecting public health and the environment. Since 1972, Water Professionals International (formerly known as the Association of Boards of Certification) has been the central water industry authority that ensures these women and men are prepared to meet the standards that their communities can trust in through our testing and certification services.
WPI membership spans 49 U.S. states/territories, 12 Canadian provinces/territories, many Canadian First Nations and U.S. tribal entities, as well as many Eastern European, Caribbean, and Middle Eastern countries/territories. WPI has assisted in the certification of more than 500,000 water and wastewater treatment professionals, including those who have earned a WPI Certification or Professional Operator (PO) Certification.
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The water resources our communities trust start with WPI Certification for operators you can trust.
Member Benefits
WPI members enjoy convenience and cost savings. As a member you have access to the WPI online certification database, networking opportunities, testing services (including expertly written and managed exams), discounted registration for our annual conference, insightful publications, and more.
WPI Member Directory
WPI members are part of our communication network and resource center for certifying authorities. WPI represents our membership on certification matters to national and international governmental agencies, organizations, and professional associations.
Volunteer Opportunities
As public servants, our incredible volunteers expand their dedication to service through their generous commitment of time and energy to WPI. From our Board of Directors, Subject Matter Experts (SMEs), and Conference Committee to our exam development committee, the opportunities are endless to make a difference today!
2024 Was An Exciting Year for Us:
WPI Year in Review
Professional Operator
WPI’s Professional Operator (PO) program is the only internationally recognized certification and professional development program for water and wastewater treatment professionals in the world. Operators with a PO designation demonstrate their mastery of protecting public health, the environment, and accelerate their careers.
Exams
WPI is committed to providing quality testing services that strengthen the certification programs of our members. We offer standardized and customized certification exams in the categories of water treatment, water distribution, wastewater collection, wastewater treatment, biological and physical/chemical industrial waste, backflow prevention assembly testing, water/wastewater laboratory, biosolids land application, and plant maintenance.
Our exams are built by operators for operators and go through a rigorous psychometric process to ensure they are fair, valid, and legally defensible.