Nutrient Reduction Strategy

The Iowa Nutrient Reduction Strategy is a science and technology-based approach to assess and reduce nutrients delivered to Iowa waterways and the Gulf of Mexico. It outlines voluntary efforts to reduce nutrients in surface water from both point sources, such as wastewater treatment plants and industrial facilities, and nonpoint sources, including farm fields and urban areas, in a scientific, reasonable and cost effective manner. The full strategy, including Annual Progress Reports and strategy revisions, are available at:

For more information on the effects of the Nutrient Reduction Strategy on wastewater treatment plants, please refer to the Nutrient Strategy wastewater fact sheet.

As part of the Iowa DNR's goal to reduce the amount of nutrients leaving the state, the Department participates in the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force (the Hypoxia Task Force [HTF]). This task force is is a federal, state, and tribal partnership established in 1997 to gain a better understanding of the causes and effects of the northern Gulf of Mexico hypoxic zone and to reduce its size, severity, and duration.

The HTF has prepared a Report on Point Source Progress in Hypoxia Task Force States to address the extent of nitrogen and phosphorus monitoring and discharge limits for major municipal sewage treatment plants within the borders of the 12 states comprising the Hypoxia Task Force. This report contains nitrogen and phosphorus loads from major sewage treatment plants. Many of the loads in the report have been derived from use EPA’s Water Pollutant Loading Tool, which accesses NPDES permit data from the EPA's Integrated Compliance Information System (ICIS). Some of the data the for major municipal sewage treatment plants in Iowa is inaccurate in EPA's ICIS database. The department is currently addressing the issues causing the inaccuracies in ICIS. However, due to the inaccuracies, the 2019 HTF Point Source Progress Report includes loads for several facilities based on raw data from the Iowa DNR.

The Iowa DNR raw nitrogen and phosphorus data for municipal majors that is used in the 2019 HTF Point Source Progress Report has been provided below. This data is from the discharge monitoring reports submitted to Iowa DNR and uploaded to the Department's NPDS database.  Please note, the spreadsheets below are only a subset of the major municipal facilities in Iowa, as the nutrient data in EPA's ICIS database is accurate for many of Iowa's major municipal facilities. The abbreviation "NDD" in the spreadsheets stands for "Nutrient Daily Data".

For more information on the Hypoxia Task Force, please see the Mississippi River/Gulf of Mexico Hypoxia Task Force website.  

Use the following link to view the Report on Point Source Progress in Hypoxia Task Force States.

Please direct questions on the data to Courtney Cswercko at