TN Nutrient Reduction Framework
Introduction, Information & ImplementationTennessee Nutrient Reduction Framework
Nutrients such as nitrogen and phosphorus are naturally occurring elements essential for healthy aquatic ecosystems. However, excessive nutrient levels can severely impact water quality, contributing to the impairment of over 3,000 miles of streams and more than 15,000 acres of reservoirs across Tennessee. To address these challenges, Tennessee initially developed a draft Tennessee Nutrient Reduction Framework in 2015—a strategic plan guiding both regulatory and voluntary efforts for long-term nutrient reduction in our water resources. Now, the Tennessee Nutrient Taskforce is leading an update to the framework, incorporating new approaches and expanded concepts to meet evolving environmental and water quality needs.
Nutrient Sources and Contributions
Nutrient loading in Tennessee’s water bodies comes from both precipitation-driven sources and treated discharges. Precipitation-driven sources, which include runoff from agricultural lands, urban areas, and natural landscapes, contribute the majority of nutrient loads, with 85% of nitrogen and 89% of phosphorus from these sources. Treated discharges account for 15% of nitrogen and 11% of phosphorus, while natural background sources provide 43% of nitrogen and 46% of phosphorus. This data underscores the importance of managing both non-point sources of nutrients and regulated discharges to achieve effective nutrient reduction across Tennessee.
While urban stormwater is regulated under the NPDES (National Pollutant Discharge Elimination System) program, non-point sources, such as agricultural runoff, are not subject to permit requirements. Instead, nutrient reductions from these sources rely on incentives, funding subsidies, and voluntary conservation efforts that help reduce nutrient losses at the landscape level.
Within the NPDES program, wastewater treatment facilities are regulated to manage nutrient discharges. The Tennessee Plant Optimization Program (TNPOP), a cornerstone of Tennessee’s nutrient strategy, provides resources for wastewater operators to enhance biological nutrient removal, focusing on low-cost optimization practices that contribute to nutrient reduction goals statewide.
Land Conservation and Nature-Based Solutions
Conserving natural areas plays a crucial role in preventing nutrient loss. Forested lands, wetlands, floodplains, and riparian corridors act as natural filters, absorbing and reducing nutrient runoff from precipitation-driven sources. Tennessee’s conservation efforts include tracking acres of preserved forests, wetlands, parks, and natural areas, along with conservation easements, to support long-term nutrient reduction.
Nature-based solutions further focus on restoring landscapes to intercept and filter nutrients before they enter water bodies. Conservation practices such as saturated buffers and riparian, floodplain, and stream bank restoration are essential components of this approach. Tennessee is developing metrics to measure restoration progress, including acres or linear feet of restored floodplains, riparian corridors, streams, and reservoir shorelines.
This Page Last Updated: October 29, 2024 at 12:27 PM