Questions about the Certified Installer of Onsite Wastewater Treatment Systems Program

For the counties in Iowa that require the CIOWTS credential, which test level is required?
The counties in Iowa that require the credential, use the Basic Level Test.  

Are there special requirements for taking the CIOWTS Test:

Yes. If less than one (1) year of onsite wastewater installation experience, completion of the Installation Overview Course is required prior to taking the CIOWTS Test.     For both the Basic and Advanced Levels you must verify that you are at least 16 years old. Proof of age must be submitted prior to taking the test at the test site (copy of driver’s license, state issued ID or birth certificate).

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) no longer offers or owns the CIOWTS test.  Is the credential still valid?   Yes, the CIOWTS credential is still in effect.  IOWWA owns and manages the CIOWTS credential.   For those who tested through NEHA, the credential renewal is still managed by NEHA however you do have an option to transfer your renewal to IOWWA.

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 $174.00 and Advanced Level renewal is $179.00.

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.  You have the option to transfer your credential to IOWWA.   Continuing education would be managed by IOWWA.

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?
Yes. If less than one year experience in the onsite industry, registering for the Installation Overview course is required.   For those who do take the course, they are provided with 12.0 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.