Stormwater Permit Information

Stormwater Permit Requirements

The NPDES stormwater program regulates stormwater discharges from three potential sources:

1. Construction activity that disturbs one or more acres or which is part of a larger project that disturbs one or more acres in total.
2. Certain types of industrial or commercial activities.
3. Many city storm sewer systems in larger communities or those near larger communities. 

There are two options available when applying for an NPDES permit for a stormwater discharge:

1. Apply for coverage under a general stormwater permit by submitting a Notice of Intent (NOI, a.k.a. application). Submit NOIs online using the Stormwater General Permit Database.
2. Apply for an individual permit.

More information on these options is available below.

No Exposure Exemption

If all industrial materials and activities at your facility are protected by a storm resistant shelter that prevents exposure to rain, snow, snowmelt, and/or runoff, you may not need stormwater permit coverage. 

To qualify for a no exposure exemption, complete and submit the No Exposure Certification Form (1.13 MB) .pdf . A No-Exposure Certification must be provided for each qualifying facility.

The no exposure exemption is ONLY available on a facility-wide basis; it is not for individual outfalls. If any industrial activities or materials at your facility are exposed to precipitation, the facility is not eligible for the exemption.

General Stormwater NPDES Permits

General NPDES permits contain terms and conditions for a certain class of facilities. These permits are not specific to any one discharger; rather, the general permit identifies which dischargers may be eligible for coverage under the permit. The stormwater general permits are applicable to discharges composed of only stormwater. Mixtures of stormwater and non-stormwater where the non-stormwater would require an individual NPDES permit are not covered by Iowa's stormwater general permits (refer to the general permits for additional details). 

The Iowa DNR has adopted three general permits for stormwater, as follows:

• General Permit #1 (465.34 KB) .pdf - Stormwater Discharge Associated With Industrial Activity (Excludes Construction)
• General Permit #2 (375.71 KB) .pdf - Stormwater Associated With Industrial Activity For Construction Activities (Land Disturbing 1 Acre Or More)
• General Permit #3 (406.14 KB) .pdf - Stormwater Discharge Associated With Industrial Activity From Asphalt Plants, Concrete Batch Plants, Rock Crushing Plants, And Construction Sand And Gravel Facilities

Additional forms and permit guidance is available on the Stormwater Permits, Guidance & Forms webpage.

Activities Not Covered Under the Stormwater General Permits:

• Any discharge with a federal effluent limit must be permitted by an individual NPDES permit. 
• Any discharge from a facility or construction site that may temporarily degrade an Outstanding National Resource Water or an Outstanding Iowa Water (OIW) must be permitted by an individual NPDES permit, as stipulated in 567 IAC Chapter 64 and in the Iowa Antidegradation Implementation Procedure (781.09 KB) .pdf . General permit coverage is not available for these discharges. 

General Permit NOI Submittal and Fees:

• Stormwater dischargers applying for coverage under a general permit must submit a Notice of Intended Action (NOI). A complete NOI includes an online or paper form, proof of public notification, and the general permit fee.
• Submit NOIs online using the Stormwater General Permit Database. 
• For coverage under a stormwater general permit, a complete NOI must be submitted and an authorization approved and issued by the DNR prior to the start of operations or soil disturbing activities.
• All stormwater general permit applications (NOIs) must be accompanied by the following fees:

Individual NPDES Permits for Stormwater

An individual NPDES permit is only applicable to one discharger and is issued for a specific discharge. Only one individual permit will be issued to a facility. If a discharger has an existing individual NPDES permit, that permit will be modified to include its stormwater outfalls. 

Individual Permit Application Forms:

• Stormwater dischargers applying for an individual permit must complete NPDES Industrial Application Forms 1, 2F, and 5, available on the NPDES Permit Application Forms webpage. Additional forms may be required if the stormwater is mixed with non-process wastewater (Form 2); process wastewater from existing sources (Form 3); or process wastewater from new sources (Form 4).
• Individual permit application forms must be submitted 180 days prior to the start of operation.

Individual Permit Application Fees:

• For individual stormwater only permits, a one-time, multiple-year fee must be submitted at the time of application. 
• For a discharge that will not reach an Outstanding Iowa Water (OIW): a five-year permit fee of $1,250. 
• For a discharge that will reach an OIW: a two-year permit fee of $500.