Nitrogen and phosphorus suffocate our streams. Excessive nitrogen and phosphorus can harm drinking water supplies, is toxic to plants, wildlife, and small pets, creates mass fish kills, and makes our streams unsafe for recreational activities. This is a special concern to TCWN because almost all of the water in Tennessee ends up in the Mississippi River and then the Gulf of Mexcio. All the nitrogen and phosphorus pollution in Tennessee contributes to the annual Dead Zone in the Gulf.
There are multiple tools available to combat nitrogen and phosphorus pollution, which result most frequenlty from animal waste, fertilizer runoff, and sewage treatment plant discharges. Here are some policy areas in which TCWN is working to address nitrogen and phosphorus polllution:
- Numeric water quality criteria – Numeric standards for pollutants are generally more effective in protecting water quality than narrative standards since they are less subjective and more readily translated into permit requirements. Unfortunately, Tennessee only has a narrative standard for nitrogen and phosphorus.
- Nutrient Reduction Strategies – EPA has requested states develop plans to address nutrient pollution. Tennessee’s Nutrient Reduction Framework is still in draft form and the state has held public meetings about its implementation.
- National Pollutant Discharge Elimination System (NPDES) effluent limits – Sewage treatment plants and other NPDES permitted dischargers contribute to the nitrogen and phosphorus pollution problems. TCWN reviews and works to improve all relevant NPDES permits.
- Agricultural contributions to nitrogen and phosphorus pollution are not regulated by NPDES permits, nor are necessary TMDL reductions mandatory for the agricultural sector. Voluntary efforts by farmers are needed to curtail much of the nitrogen and phosphorus pollution running off their lands.
Nitrogen and Phosphorus threaten our water quality. Reducing these dangerous pollutants is a priority of TCWN.