The Illinois Nutrient Loss Reduction Strategy (Illinois NLRS or the strategy) is a framework for using science, technology, and industry experience to assess and reduce nutrient loss to Illinois waters and the Gulf of Mexico. The strategy will direct efforts to reduce nutrients from point and non-point sources in a coordinated, primarily voluntary, and cost-effective manner.
Nutrient loss and runoff is a major threat to water quality in Illinois. State and local efforts over the decades to control nutrients have yielded positive results, but new and expanded strategies are needed to secure the future health of our water throughout Illinois and the Mississippi River Basin.
The Illinois NLRS builds upon existing programs to optimize nutrient loss reduction while promoting increased collaboration, research, and innovation among the private sector, academia, non-profits, wastewater agencies, and state and local government. It does not call for new regulations for either point or non-point sources.
The plan will be introduced and followed throughout the state with leadership from the Illinois Environmental Protection Agency, the Illinois Department of Agriculture, the Illinois NLRS policy working group, and newly formed committees. Emerging science, new technology, and practical experience will continue to identify the financial benefits and costs of the strategy’s recommendations and inform future policy. Success will require that stakeholders closely collaborate and acknowledge their evolving and increasing mutual dependency.
Twelve other states in the Mississippi River watershed have Nutrient Reduction Strategies. Find more information and read their strategies here.
Agricultural Contributions
Agricultural runoff is a significant source of total phosphorus and nitrate-nitrogen loading into Illinois waterbodies. Total phosphorus losses are typically due to soil erosion into surface waters, while nitrate-nitrogen losses commonly occur when nutrients are carried in water via tile drainage. However, both nutrients can be lost by either route, and both routes affect surface and ground water quality.
According to the Illinois science assessment, agricultural runoff contributes 80 percent of the nitrate-nitrogen and 48 percent of the total phosphorus losses exported from the state. The non-point source nitrate-nitrogen yield average was estimated at 10 lb/acre/yr, with 27 eight-digit Hydrologic Unit Code (HUC) watersheds showing greater losses. The greatest nitrate-nitrogen losses were found in the tile-drained northern two-thirds of the state, where artificial drainage is common and the land use is dominated by row crop agriculture. Total phosphorus non-point source losses were estimated at an average yield of 1.4 lb/acre/yr and were typically greater in southern Illinois and lower in the northernmost parts of the state.
Click map images for larger versions: