NPDES General Permit #9 for Dewatering Activities and Residential Geothermal Discharges

Note: This is a PROPOSED GENERAL PERMIT. No discharges are authorized under this permit at this time.

The department is developing a new general permit. This permit would authorize discharges from the following activities:

  • Excavation dewatering associated with construction activity
  • Temporary groundwater dewatering to facilitate construction activity
  • Residential open-loop geothermal heating and cooling systems

The permit would cover dewatering discharges to surface waters of the state and to the ground surface. Discharges from geothermal systems that do not reach navigable waters are already exempted by rule from obtaining operation permits. Therefore, only discharges to navigable waters from residential geothermal systems will by authorized by the new permit.

Draft General Permit #9 – December 22, 2017

Rationale for General Permit #9

Notice of Intended Action for EPC - General Permits #8 & #9

Helpful Documents

Two documents have been developed to help people determine what permit requirements are applicable in a given situation. The Matrix is a series of yes/no questions. As you answer each question, you will be directed to the next question or the requirements. You may prefer this if you are a linear thinker or like flow charts. The Requirements Table has all the requirements laid out in one document, so you can easily find the requirements for your situation. You may prefer this if you are a visual thinker, or if you wish to compare requirements among different situations.

General Permit #9 Decision Matrix

General Permit #9 Requirements Table


Currently, people conducting discharges that would be authorized by the permit can either pursue an individual permit or discharge illegally. Obtaining an individual permit requires an investment of time and money that is disproportionate to the impact these discharges usually have on the environment. Not only is discharging without a permit illegal, but the discharges may occur without environmental controls. DNR receives many requests for guidance from those who are interested in avoiding negative environmental impacts.

This permit will benefit dischargers by providing them a permit shield without the time and cost of obtaining an individual permit. Unlike individual permits, no fees are associated with GP#9. It also provides dischargers with guidance for minimizing the impact of these discharges on water quality. This permit will benefit the environment by providing requirements and guidance for conducting these discharges in a manner that will avoid negative impacts on water quality. This permit will benefit DNR by providing a mechanism to authorize these discharges using very little staff time, which can then be spent on higher-risk discharges.

What this permit will do:
  • Authorize temporary and limited discharges that can meet water quality standards.
  • Authorize certain discharges that are not temporary and limited but that are approvable under Iowa’s Antidegradation Implementation Procedure.
  • Provide a permit shield to authorized discharges.
  • Establish eligibility requirements and best management practices to ensure protection of water quality.
  • Reduce the number of permittees required to pursue individual permits.
  • Greatly reduce the amount of time needed to obtain permit coverage for most permittees.

What this permit will NOT do:
  • Authorize discharges that will cause violations of water quality standards.
  • Authorize discharges from groundwater remediation systems.
  • Authorize discharges to Outstanding Iowa Waters or state-owned lakes.
  • Establish burdensome notification requirements.
  • Require fees.
  • Eliminate the department’s ability to require a discharger to apply for an individual permit.
  • Eliminate a discharger's ability to apply for an individual permit.

General permits must be adopted into rule and discharges authorized by the permits must be added to the list at 567 IAC 64.3(4).
The Notice of Intended Action for Proposed General Permits #8 and #9 was approved by the Environmental Protection Commission on January 17th.  The Notice was published in the Iowa Administrative Bulletin on February 14th as ARC 3625C.
Stakeholder Input:

Three public hearings will be held in March 2018, as follows:

March 7, 2018 4 pm
Coralville Public Library
1402 5th St., Coralville, IA
Meeting Room A.
Hearing attendees should park on the lower level of the parking structure.

March 8, 2018 4 pm
Harlan Public Library
718 Court St., Harlan, IA
Hearing attendees should park on the west side of the building.

March 14, 2018 4 pm
Urbandale Public Library
3520 86th St., Urbandale
Meeting Room A.

Written comments should be submitted by 4:30 pm, March 19, 2018. Direct comments to: Wendy Hieb 502 East 9th Street Des Moines, IA 50319
Fax: 515.725.8202

Persons who wish to make oral comments at a hearing will be asked to state their names for the record and to confine their remarks to the subject of the proposed rules.

Any persons who intend to attend a public hearing and have special requirements, such as those related to hearing or mobility impairments, should contact the Department and advise of specific needs.

More Information:

Water Quality Standards:
567 IAC Chapter 61

Statewide Standards for Contaminants in Soil and Groundwater:
DNR Cumulative Risk Calculator

For more information on the development of this permit, please contact Julie Faas at 515-725-8409 or