Illicit Discharge

About Illicit Discharge

Illicit discharge is any discharge into the storm sewer that is not comprised entirely of stormwater. Illicit discharges may be a result of industrial activity, deposits of oil on parking lots, excess lawn fertilizer and yard clippings, and a variety of other sources which pollute water with turbidity, excess nutrients, and bacteria. Illicit discharges can also be from failing septic systems or improperly connected sewer lines. Dumping liquids or putting any refuse into storm drain inlets is also considered an illicit discharge and eliminating these discharges is an important step in protecting Ankeny's waterways.

The City of Ankeny has adopted an illicit discharge detection and elimination (IDDE) program, which is mandated by the Municipal Separate Storm Sewer System (MS4) Permit from the Iowa Department of Natural Resources. Under the MS4 Permit Ankeny is required to adopt an illicit discharge prohibition ordinance, sample discharge from storm sewers, and map the storm sewer system.

View Ankeny's Illicit Discharge Ordinance.

How the City Manages Illicit Discharges

To detect illicit discharges, inspections of the outfalls are completed. An outfall is where stormwater is drained from a pipe or drainage-way into our city's creeks or water bodies. Each outfall is inspected as required by the MS4 permit and as-needed. Samples of suspected illicit discharge are collected and a reconnaissance of the outfall is performed. Once a problem is identified, the source will be determined. The responsible party will be notified and be required to eliminate the discharge.

Examples Of Illicit Discharge

  • Septic Tank effluent
  • Improper oil disposal
  • Grass clippings/leaves left in the street
  • Commercial car wash wastewater
  • Sanitary wastewater
  • Lawn-watering/irrigation
  • Street washing/sweeping
  • Water line flushing
  • Residential car washing
  • Any activity with a NPDES discharge permit

What You Can Do To Prevent Illicit Discharge

The best ways to keep illicit discharges from occurring is to follow good housekeeping practices. This includes recycling or properly disposing of waste, keep waste receptacle lids secured on windy days, and cleaning up spills or litter immediately. It is also important to keep grass clipping and leaves off the street. Another way to help is keep your neighborhood storm drains clean of debris and litter.

Report Illegal Dumping or Illicit Discharge

While the City of Ankeny has established the Illicit Discharge Detection and Elimination Program, community involvement is a key component to the program's success.  If you see any illegal dumping or signs of illicit discharge in surrounding waterways, please contact us at the following numbers:

  • Stormwater Hotline:515-963-3550
    • After Hours (Polk County Dispatch): 515-286-3333
  • Iowa Department of Natural Resources Field Office 5: 515-725-0268
  • Iowa Department of Natural Resources Emergency Spill Hotline: 515-725-8694