Wastewater and NPDES Rules


General Information about Iowa's Wastewater and NPDES Rules

The Iowa Administrative Code (IAC) contains several chapters regulating the direct discharge of wastewater to waters of the state. The chapters containing most of the wastewater permit regulations are as follows:

Rules regarding NPDES permits for Animal Feeding Operations (Chapter 65) can be found on the Animal Feeding Operations page. Rules regarding onsite (private) wastewater systems (Chapters 68, 69, and 93) can be found on the Private Septic Systems page. The Water Quality Standards (Chapter 61) can be found on the Water Quality Standards page.

The chapters above are regularly updated through the state's rulemaking process. Please refer to the Current NPDES Rulemaking Actions section below for more information on any proposed rule changes.



Current NPDES Rulemaking Actions


Proposed Renewal of NPDES General Permit Nos. 1, 2, 3, and 4:

The NPDES Section is proposing rule changes to Chapters 60 and 64 of the Iowa Administrative Code to renew four of Iowa’s general permits for storm water (GPs #1, #2, and #3) and private sewage disposal systems (GP #4). The new effective dates for all four general permits will be March 1, 2023. The proposed revisions to GPs 1 through 4 and to Chapter 60 will improve the clarity and readability of the requirements, definitions, and standard conditions, and will ensure consistency with corresponding federal regulations. The proposed revisions do not affect the substance of the general permits.

The Environmental Protection Commission approved the Notice of Intended Action for the proposed rule at their meeting on August 16, 2022. The Notice was published in the Iowa Administrative Bulletin as ARC 6501C on September 9, 2022.

A public hearing on the proposed rule and general permit renewals will be held via Zoom on September 28, 2022, at 2:00 pm. The Zoom meeting registration link is: us02web.zoom.us/meeting/register/tZApcOmtrzwqH9N8GgCQEO1aQyhpDvZ6Ibn8. After registering, participants will receive a confirmation email containing information about joining the meeting.

Persons who wish to make oral comments at the public hearing must submit a request to Courtney Cswercko prior to the hearing to facilitate an orderly hearing. Persons who wish to make oral comments at the public hearing will be asked to state their names for the record and to confine their remarks to the subject of this proposed rule making. Any persons who intend to attend the public hearing and have special requirements, such as those related to hearing impairments, should contact the Department and advise of specific needs.

Please use the following links to view the GP 1 - 4 draft permit changes:

Questions about the hearing or the proposed rulemaking can be directed to Courtney Cswercko at 515-322-2157 or Courtney.Cswercko@dnr.iowa.gov.


Renewal of NPDES General Permit Nos. 5, 6, 7, 8 and 9:

On August 16, 2022, the Environmental Protection Commission adopted a rule change to Chapter 64 of the Iowa Administrative Code to renew five of Iowa’s general permits for wastewater discharges. These general permits cover certain wastewater discharges from mining and processing facilities (GP5), well construction activities (GP6), pesticide applications (GP7), hydrostatic testing, tank ballasting, and water lines (GP8), and dewatering activities and household geothermal systems (GP9). 

GP8 and GP9 were renewed because the current versions will expire on June 30, 2023. The adopted changes to these two general permits will clarify existing permit requirements and address needs identified during the initial permit term.

GP5, GP6, and GP7 were renewed at the same time in order to align the effective dates for all five general permits so that future renewal rule makings for these permits can be combined. Minimal changes were made to these three general permits.

The Notice of Intended Action for GPs 1 - 5 was published in the Iowa Administrative Bulletin (IAB) on June 15, 2022 as ARC 6358C. A public hearing was held via Zoom on July 6, 2022. The Adopted and Final Rule for the renewed general permits was published in the IAB on September 9, 2022 as ARC 6493C. The renewed general permits will become effective on July 1, 2023.

Please use the following links to view the adopted permit changes:

Questions about the rulemaking can be directed by phone or email to David Schelling at 515-217-0875 or David.Schelling@dnr.iowa.gov.



Past NPDES Rulemaking Actions


Wastewater Cleanup Rule Changes (Chapters 60-64): Updates to several portions of the wastewater rules became effective on March 16, 2022. The Chapters included in the rulemaking were 60, 61, 62, 63, and 64. The changes are summarized below by Chapter.

  • Chapter 60 - added and updated definitions, removed old forms, and added language on electronic form submittal.
  • Chapter 62 - updated the Federal effluent and pretreatment standards date reference and added a reference to the federal dental effluent limitation guidelines.
  • Chapter 63 - added CFR references; clarified test procedure requirements; updated the rule-referenced Supporting Document for Permit Monitoring Frequency Determination; added new rules on electronic reporting; rescinded the land application monitoring table; rescinded the preservation techniques, containers and holding times table and replaced it with a CFR reference; and moved monitoring well sampling language to a new rule.
  • Chapter 64 - simplified the general permit rules; modified the operation permit period; updated public notice and public hearing rules; updated disadvantaged community eligibility requirements; added specific fee amounts from Iowa Code 455B.197; and added a rule about the Nutrient Reduction Exchange (NRE).

Please use the links at the top of the page to view the updated wastewater rules.


Sludge Rule Changes (Chapter 67): Updates to the sludge/biosolids rules in Chapter 67 became effective on March 16, 2022. The rule making cleaned up and modified the sludge rules for readability and to align with governing federal law. Use this link to view the updated Chapter 67 rules.



Summary of Rulemaking Procedures:

When the NPDES Section is considering a change to the wastewater rules, a draft rule package is developed and a public meeting is scheduled to gather initial stakeholder input on the draft rules. After the initial stakeholder comments are incorporated into the draft rules, the NPDES Section prepares an internal rulemaking package for review by DNR Legal staff and the Governor's Office. Once DNR Legal staff and the Governor's office have reviewed and approved the proposed rule, the rulemaking package is presented to the Iowa DNR Environmental Protection Commission (EPC) for approval as a Notice of Intended Action. If approved by the EPC, it is published in the Iowa Administrative Bulletin (IAB) as a Notice of Intended Action (NOIA). Once the NOIA is published, the rule is discussed at the next legislative Administrative Rules Review Committee (ARRC) meeting. After a public comment period in which hearings are held and comments are accepted, the proposed rule is presented to the EPC for approval as a Final Rule. If a final rule is approved by the EPC, after consideration of public comments, it is published in the Administrative Bulletin as a Final Rule. The final rule will be presented to the ARRC after it is published and before it becomes effective. Please see the summary steps below:

Draft rule package prepared - Public meeting on draft rule - Comments incorporated into draft rule - DNR Legal review - Governor's Office review - NOIA presented to the EPC - NOIA publication in the IAB - ARRC review of NOIA - Public comment period - Responsiveness summary prepared - Final Rule presented to EPC - Final Rule publication in the IAB - ARRC review of Final Rule - Final Rule becomes effective

For more information regarding the rulemaking procedure and the wastewater rules, please contact Eric Wiklund at 515-630-9970 or eric.wiklund@dnr.iowa.gov or Courtney Cswercko at 515-322-2157 or courtney.cswercko@dnr.iowa.gov.