Polk County, IA Environmental Rules: Erosion Control (2026)

Article 8, Division 2, Section 1 explains the rationale: uncontrolled soil erosion damages drainageways, raises road and storm sewer maintenance costs, endangers roadways and pollutes streams. Section 2 sets the applicability trigger at fill over three feet, excavation over five feet, or any grading or clearing disturbing 5,000 square feet, and separately flags that some construction sites also need Iowa DNR coverage under NPDES General Permit No. 2. Section 3 adopts the Iowa DNR's Construction Site Erosion Control Manual by reference, requires perimeter protection and a gravel entrance drive at least 25 feet from the public roadway on any soil-disturbing job, though the Zoning Administrator may waive that if existing ground cover doesn't warrant it, or demand more protection if what's in place isn't working.

Section 4 puts Public Works in charge of issuing permits, requires the application to be signed by the title holder, and includes a Grading Plan from a licensed engineer (unless waived), a SWPPP, and the permit fee; the permit is valid one year and must be renewed with updated information and fee. Section 5 layers in extra permits for floodplain filling, but waives a separate Grading Permit where the work is already covered by a Demolition or Building Permit with an approved NPDES SWPPP. Section 6 exempts crop production, cemetery graves, life-safety emergencies, and public improvements from the permit requirement entirely.