IDEM’s Total Nitrogen Monitoring Initiative

Nutrient pollution to our waterways is one of the United States’ top environmental challenges.  Public health issues due to harmful algal blooms (a rapid accumulation of algae) impact waterways used for drinking and recreation.  This happens by either blocking out sunlight and depleting oxygen for aquatic life or by secreting toxins into drinking water sources.

On September 22, 2016, the U.S. Environmental Protection Agency (EPA) released a memorandum titled “Renewed Call to Action to Reduce Nutrient Pollution and Support for Incremental Actions to Protect Water Quality and Public Health.”  This memorandum gave examples of problems related to nutrient pollution. It provided the EPA’s desire to support and aid state planning and projects related to reducing nitrogen and phosphorus pollution contributing to harmful algal blooms.  The EPA recommended that states set a goal to include monitoring requirements for total phosphorus and total nitrogen in National Permit Discharge Elimination System (NPDES) permits for major municipal wastewater facilities (facilities with average design flows greater than 1 MGD).

Currently, Indiana has not implemented any statewide effluent limitations for total nitrogen.  Instead, the Indiana Department of Environmental Management (IDEM) is proposing all major sanitary dischargers with an average design flow of 1 MGD or higher begin monitoring for total nitrogen as a part of their next NPDES renewal.  Total nitrogen is to be monitored and reported to IDEM on a monthly basis to collect data on nitrogen loadings in Indiana waters.  Such data is intended to aid the State with future updates to total nitrogen and nutrient pollution reduction.

Additional information on IDEM’s Total Nitrogen Initiative can be found here: Total Nitrogen Monitoring Frequently Asked Questions

For questions, please contact Brady Dryer, Commonwealth’s Compliance Manager.

(317) 888-1177