NPDES General Permits

Iowa DNR General NPDES Permits:

The Iowa DNR has issued seven General NPDES Permits.  They are as follows:
  • General Permit No. 1, Storm Water Discharge Associated with Industrial Activity, effective October 1, 2012, to October 1, 2017.
  • General Permit No. 2, Storm Water Discharge Associated with Industrial Activity for Construction Activities, effective October 1, 2012, to October 1, 2017.
  • General Permit No. 3, Storm Water Discharge Associated with Industrial Activity from Asphalt Plants, Concrete Batch Plants, Rock Crushing Plants and Construction Sand and Gravel Facilities, effective October 1, 2012, to October 1, 2017.
  • General Permit No. 4, Discharge from Private Sewage Disposal Systems, effective August 15, 2012 to August 15, 2017.
  • General Permit No. 5, Discharge from Mining and Processing Facilities, effective July 20, 2016 to July 19, 2021.
  • General Permit No. 6, Discharge Associated with Well Construction Activities, effective March 1, 2015, to February 28, 2020.
  • General Permit No. 7, Pesticide General Permit (PGP) for Point Source Discharges to Waters of the United States From the Application of Pesticides, effective May 18, 2016, to May 17, 2021.

To obtain more information on the storm water general permits (#1, #2, and #3), refer to the Storm Water Permitting Requirements Information page.  To see information on the discharges authorized under General Permits #1, #2, and #3, please see the Online Storm Water Permits database.  To obtain more information on General Permits #4, #5, #6, and #7, please follow the links above. 


Proposed General Permits 8 and 9:

The Iowa DNR is developing two new general permits that will authorize discharges from hydrostatic testing, tank ballasting, and water line testing (General Permit #8) and that will authorize discharges from dewatering activities and private residential geothermal heating and cooling systems (General Permit #9).  The general permits would only authorize discharges that will not cause violations of state water quality standards. The eligibility and notification requirements of the permits will reduce the burden for dischargers to obtain permit coverage (compared to individual permits), while ensuring that higher-risk discharges are reviewed by the DNR and authorized when and if water quality will be protected.

For more information on these proposed permits, please refer to their specific webpages (linked above).


Basic Information on NPDES General Permits:

General NPDES Permits allow the DNR to allocate resources in an efficient manner to provide more timely permit coverage.  For example, many facilities that have common elements may be covered under a general permit without expending the time and money necessary to issue individual permits to each facility.  In addition, using a general permit ensures consistency of permit conditions for similar facilities.

A General NPDES Permit covers multiple facilities within a specific category.  General permits can be cost-effective, as a large number of facilities can be covered under a single permit.  A general permit may be written to cover categories of point sources having common elements.

The process for developing and issuing General NPDES Permits is similar to the process for individual permits.  However, there are differences in the order of events.  DNR first identifies the need for a general permit by collecting data demonstrating that a group of dischargers has similarities that warrant a general permit. In deciding whether to develop a general permit, IDNR will consider the following:

  • Are there a large number of facilities to be covered?
  • Do the facilities have similar production processes or activities?
  • Do the facilities generate similar pollutants?
  • Do only a small percentage of the facilities have the potential for violations of water quality standards?

The remaining steps of the permit process are similar to those for individual permits.  DNR develops the draft general permit and rationale, issues a public notice, addresses public comments, and issues the final permit.  However, General NPDES Permits in Iowa must be adopted by rule, so the public notice, response to comments, and issuance of the general permit are all part of the rulemaking process.  For more information on the rulemaking process, see the NPDES Rules page.

After a general permit has been issued, facilities may either submit a Notice of Intent (NOI) to DNR for coverage under the permit (General Permits No. 1, 2, 3, 4, and 5), or a facility may automatically be covered by the general permit (General Permits No. 6 and 7).  Upon receipt of an NOI, DNR may either request additional information from the facility, notify the facility that it is covered by the general permit, or require the facility to apply for an individual permit.

To apply for coverage under storm water General Permits #1, #2, and #3 online, please refer to the  Online Storm Water General Permit Authorization page.