Questions about the Certified Installer of Onsite Wastewater Treatment Systems Program

Are there upcoming in-person Installation Overview Course and CIOWTS credential testing events?
Yes. The Installation Overview Course and CIOWTS credential test is planned for Tuesday, Dec. 7 and Wednesday, Dec. 8, 2021.  It will be held at the Arlington Community Event Center, 853 Main St., Arlington IA.   If you are interested in taking the CIOWTS credential test, please complete and submit the application.  The application can be downloaded from the "Certification" tab on the IOWWA web site.    Generally the Installation Overview Course and CIOWTS test is set for March or April  and again in November or December.   Depending on applications received, a mid-summer date is added for the CIOWTS test only.  

Does IOWWA accept online training for the CIOWTS continuing education?
Yes.  IOWWA will accept up to 6 CE hours of online training per credential cycle and 2 CE hours per credential cycle for county contractor meetings (even if multiple county contractor meetings are attended). IOWWA tracks CE hours received from IOWWA and DMACC-sponsored events for CIOWTS credential holders. Credential holder has responsibility to submit hours to

Certified Installer of Onsite Wastewater Treatment Systems (CIOWTS) Credential
As of December 31, 2017, the National Environmental Health Association (NEHA) will no longer offer the CIOWTS  test through their credentialing program.   Is the credential still valid?  
Yes, the CIOWTS credential is still in effect.    NEHA and the IOWWA will still recognize the credential.   The CIOWTS test will no longer be offered through NEHA.

Can I still be certified after December 31, 2017?
Yes, the IOWWA will be continuing the CIOWTS program in the state of Iowa.   IOWWA now owns the CIOWTS credential test and will continue to manage the credential.  

How long is the CIOWTS credential cycle?
The credential cycle starts on the first day of the month that you took the test.    The credential runs on a two year cycle.    As an example, for someone who tested on March 15th, 2016 the credential cycle would go from 03/01/2016 to 02/28/2018.

Is there a renewal fee at the end of the two year credential cycle?
Yes, there is a renewal fee that needs to be paid prior to the current cycle expiration date.   IOWWA will email/mail an invoice to you.   Currently the Basic Level renewal is $95.00 and Advanced Level renewal is $110.00.

Where do I send my renewal fee to?
If you took the exam through the IOWWA we will email/mail you an invoice for the renewal fee.  Payment options will be provided, including payment online.

Does IOWWA have an online option for paying the CIOWTS renewal fee?
Yes, in the drop down list on the "Credential" tab there is an option to pay the credential renewal online using a credit card.     (If paying by check, the invoice provides that option.)

My CIOWTS application was handled by NEHA and I took my certification exam though them.  Does my renewal now have to go to IOWWA?
No, NEHA is still managing the credential so you will be able to submit your continuing education information and renew your credential with them.

I currently renew my CIOWTS credential with NEHA.   Can I transfer that to the IOWWA?
Yes, IOWWA will track your continuing education hours (if attending IOWWA events) and send you an invoice when your credential cycle is up.  Please note:  If you choose this option, IOWWA will recognize you as being certified and maintain your credential.  However, you will no longer be recognized through NEHA.

Where do I go to find information on the upcoming CIOWTS exam?
You can check on the "Training and Events" tab at or the "Certification" tab.    We also advertise all the workshops, including the CIOWTS exam, in the IOWWA Onsite Observer newsletter as well as sending out email.

When is the next paper/pencil CIOWTS test?
Refer to the "Trainings and Events" tab for the upcoming CIOWTS testing dates and locations.   If you are interested in testing, please email your contact information to  

Is it mandatory to take the Installation Overview course prior to the CIOWTS test?
No, signing up for the Installation Overview course is optional.   For those who do take the course, they are provided with 12.5 hours of continuing education that can be used for the first two-year credential cycle.

Will I still be able to take the exam online?
No, not at this time.  We would like to continue the online exam option however that is not an option now.  Please check back for more details as they develop.