Iowa State Overview

When Iowa was delegated the National Pollutant Discharge Elimination System (NPDES) Permitting Program for wastewater discharges, special delegation was requested for stormwater discharges as well. The Iowa Department of Natural Resources (DNR) has continued to work diligently in a variety of ways to improve stormwater quality within the State of Iowa.      

The Iowa Department of Natural Resources Stormwater Management Program regulates any construction activity that: (1) disturbs one (1) or more acres; or (2) disturbs less than one (1) acre which is part of a larger project that will ultimately disturb one (1) or more acres in total. The IDNR regulation mandates that an operator whose construction project falls under one of the two aforementioned categories be covered under the Construction General Permit before any construction activity commences and/or soil is disturbed at the site.

As per the Iowa Department of Natural Resources, all construction activities that disturb one or more acres are covered under “General Permit No.2.” The following apply to coverage under “General Permit No. 2”:

• General Permit coverage is required to be continued until all construction has ceased and the disturbed area(s) has attained final stabilization with a permanent, perennial, vegetative cover.

• Construction is not complete until all houses and buildings are constructed and the ground has achieved final stabilization. Permit coverage must be maintained until this requirement is fulfilled.

• If only one year of permit coverage was initially purchased and, after one year, the ground is not completely stabilized, permit coverage must be renewed.

• Permit coverage must be maintained after initial grading and street construction for residential and commercial developments.