CERTIFIED INSTALLER OF ONSITE WASTEWATER TREATMENT SYSTEMS (CIOWTS) CREDENTIAL
The primary purpose of the credential is to set a standard of practice and create a baseline of knowledge for onsite wastewater system installations. Iowa counties are encouraged to adopt regulations providing for the certifying of installers and to require the CIOWTS credential.
Counties currently requiring the Basic Level CIOWTS credential:
Benton, Black Hawk, Bremer, Buchanan, Butler, Cedar, Chickasaw, Clayton, Dallas, Delaware, Floyd, Grundy, Hamilton, Hardin, Iowa, Jasper, Jones, Linn, Marion, Scott, Story, Tama, Warren, Washington, and Winneshiek. Check with the county sanitarian for specific requirements. A map showing the counties that require the CIOWTS credential can be found in the Documents and Files section at the bottom of this page.
The IOWWA Certified Installer of Onsite Wastewater Treatment Systems (CIOWTS) Handbook can be viewed or downloaded in the below "Documents and Files" section.
A pass score of 70% or higher must be achieved to receive the CIOWTS credential. The credential runs on a two-year cycle. During each two-year cycle, the credential holder must have a minimum of 12.0 hours of continuing education earned in the onsite wastewater industry. IOWWA has events scheduled throughout the year that provide continuing education approved for the CIOWTS credential. For those taking the Installation Overview course prior to a scheduled test, the 12.0 CE hours earned will be applied to the first two-year cycle.
CIOWTS Test Study Guide: This study guide, published by the Consortium of Institutes for Decentralized Wastewater Treatment, is a 464-page notebook that serves as a self-study aid for those interested in testing for the Certified Installer of Onsite Wastewater Treatment Systems (CIOWTS) credential. The handbook is also a valuable office or field reference guide and can be purchased as a publication or PDF file. Order through Iowa State University: Installation of Wastewater Treatment Systems Manual. NOTE: You must set up an account to purchase - the password must be a MINIMUM of 12 characters.
IOWWA Member and Non-Member CIOWTS List: To review IOWWA members and non-members who have the CIOWTS credential, please refer to the "CIOWTS Members and Non-Members List" PDF file in the Documents & Files section below.