Report details Illinois’ nutrient loss efforts

SPRINGFIELD, Ill. — The 2025 interim goals set by the Illinois Nutrient Loss Reduction Strategy are fast-approaching, but the numbers needed are still not there.

In its biennial report, the Illinois NLRS noted, “statewide nutrient load levels are still higher than interim targets, with phosphorus being a significant concern.”

The report provides updated water quality measures for 2021 and 2022.

The 2017-2021 five-year average nitrate-nitrogen loads increased 4.8% to 416 million pounds annually, and total phosphorus loads increased 35% to 46 million pounds, compared to the 1980-1996 baseline. River flow, or water yield, was 23% higher than the baseline, according to the report.

However, the five-year averages for nitrate-nitrogen loads, total phosphorus loads and streamflow all decreased in 2017-2021 compared to the previous 2016-2020 averages of 16.2%, 42% and 30% above baseline.

“Statewide nitrate-nitrogen and total phosphorus loads have been highly correlated with water yield, which itself is highly correlated with precipitation,” the report said.

The long-term objective of the strategy is a 45% reduction in total phosphorus and total nitrogen loads originating in Illinois, with interim targets of a 15% decrease in nitrate-nitrogen and a 25% decrease in total phosphorus by 2025.

Agricultural, point sources such as sewage treatment facilities, and urban stormwater sectors are monitored as part of NLRS.

“Nutrient load increases are driven by a variety of factors, such as increased streamflow, legacy nutrients, nutrient management and other unknown sources. The effects of climate change are also contributing factors,” the report said.

“Despite the continued implementation of nutrient loss reduction practices across sectors, barriers remain. Particularly, the agriculture sector requires a swifter and more extensive adoption of conservation practices to meet the established goals.”

Agriculture Sector

In the agricultural sector, surface runoff and subsurface drainage are the primary sources of nutrient loss. The NLRS recommends a variety of in-field and edge-of-field practices to reduce nutrient loss from these sources.

“During 2021-2022, conservation efforts jointly funded by the Illinois Department of Agriculture and Illinois EPA successfully prevented 73,000 pounds of nitrogen and 30,000 pounds of phosphorus from entering the state’s waterways,” the report said.

“These efforts included IDOA’s Partners for Conservation and Fall Covers for Spring Savings programs, Illinois EPA’s Section 319 Non-Point Source Pollution Control Program and multiple U.S. Department of Agriculture programs.”

A 2022 survey by the National Agricultural Statistics Service provided insights into farmer awareness and strategy implementation levels.

Of the surveyed Illinois farmers, 55% reported to have knowledge about the strategy, an increase from 43% in 2020. The survey also highlighted adoption rates of fertilization practices for the 11 million acres of corn planted in 2021.

The nitrogen fertilization methods were reported by the farmers as:

• 76% managed using the Maximum Return to Nitrogen.

• Corn fertilization timing: 25% fall/winter, 35% fall-spring split, 40% spring.

• 85% used nitrogen inhibitor for fall/winter-applied anhydrous ammonia, 83% used nitrogen inhibitor for spring-applied.

Data from the Conservation Technology Information Center’s Operational Tillage Information System indicated 71% of cropland acres in Illinois are managed using conservation tillage which leaves 15% or more residue.

The Illinois Fertilizer and Chemical Association led a series of fall and spring surveys over four years, 2018-2022, focused on nutrient management practices.

IFCA’s fall surveys reported a four-season average of 91% of respondents who applied anhydrous ammonia after the fall application date recommended by University of Illinois. This method was used across 9.6 million acres.

Also, an average of 90% of respondents indicated that fall-applied anhydrous ammonia included a labeled nitrification inhibitor. On average, 78% of total nitrogen rates were applied using MRTN rates.

Grass buffers of at least 30 feet on both banks were present next to half of the waterways, rivers and tributaries adjacent to cropland in Illinois, covering an area of 62,200 acres. Another 2.7%, 3,300 acres, were grass buffered on one bank.

A fifth, 21.4%, were entirely unbuffered, indicating an opportunity to expand stream buffers by 26,700 acres in Illinois.

Point Source Sector

A point source is any site of discharge into a waterway, such as municipal sewage treatment facilities and industrial wastewater treatment facilities.

By 2022, the point source sector exceeded the strategy’s 25% interim total phosphorus reduction goal for 2025, by reducing phosphorus discharges by 6.2 million pounds, a 34% decline since 2011.

This achievement is largely due to compliance with Illinois EPA’s National Pollutant Discharge Elimination System permit program which mandates treatment facility improvements and optimizations.

Urban Stormwater Sector

In the urban stormwater sector, water quality improvement efforts focus on managing runoff and reducing the duration and intensity of flooding.

In 2021-2022, initiatives funded by the Illinois EPA Green Infrastructure Grant program kept 1.2 million gallons of stormwater out of waterways through 11 Illinois EPA funded projects.

A majority, 70%, of communities with Municipal Separate Storm Sewer Systems have adopted annual street sweeping and leaf collection practices.

The stormwater sector continues to provide public education on nutrient loss reduction from public and private property.

Adaptive Management

“Nutrient pollution has neither a single source nor a single solution. This makes versatility, fluidity and collaboration crucial tenets of the Illinois NLRS. Adaptive management allows the strategy to be a living document focused on traditional and new technologies and practices,” the report said.

“As our climate shifts, and as research and technological advancements emerge, the recommended approaches to achieve the strategy’s goals will adapt accordingly.

“Nutrient loads are still increasing, and there is an urgent need to continue supporting work in nutrient loss research, public education, outreach and technical support, especially within the agriculture sector.”

While the strategy addresses nutrient loss on a statewide level, there is a growing emphasis on localized, watershed-specific initiatives. These initiatives attract investments from federal, state and nongovernment partners.

Locally led watershed-based planning remains a priority for meeting smaller-scale water quality goals. For example, the Illinois EPA has provided financial assistance for the development of 143 watershed-based plans since 2011.

Numerous organizations are also investing in research and incentive programs targeting specific watersheds.

On a positive note, the significant reduction in point source phosphorus has already exceeded the 2025 interim goal of a 25% decrease.

While there is evident progress in the agricultural sector’s adoption of recommended conservation practices, there is an urgent need to ramp up adoption of practices to meet the 2025 interim goals for nutrient loss reduction, the report said.

Conclusion

Nutrient levels in Illinois waterways continued to increase in 2021 and 2022 compared to baseline measurements, and the NLRS partnership anticipates the strategy will likely fall short of its 2025 interim goals, particularly for phosphorus.

This is despite multisector investments in resources and practices that support nutrient loss reduction across the state.

“While Illinois has a long journey ahead to meet its nutrient loss goals, these biennial reports consistently offer valuable insights that shape decisions, foster collaborations and spur innovative solutions,” the report concluded.

Illinois Corn Statement

After reading the results of the Illinois NLRS Biennial Report, Illinois Corn Growers Association Director Don Guinnip, of Marshall, issued the following statement: “Illinois Corn Growers Association farmer members, directors and staff value the evaluation available to us via the NLRS Biennial Report. Without evaluation, it is impossible to identify progress.

“Farmers also understand that there are challenges in tracking and quantifying information like this, and we look forward to the Illinois Ag Retail Survey results to help us better understand the entire nutrient loss picture for Illinois.

“Each progress report helps Illinois agriculture better understand and amplify the needs of Illinois farmers for support — both expertise and financial resources — to help us achieve the reduction goals. New funding and new support are becoming available every day to power the changes farmers need to make on every Illinois acre.

Illinois Soybean Statement

“The Illinois Soybean Association will continue its support of Illinois’ farmers by highlighting the on-going and voluntary NLRS investment, providing farmers financial and technical resources for the implementation of conservation practices, stressing the importance of a science-based, balanced approach that considers impacts to all Illinois stakeholders,” said Illinois Soybean Association Chairman Ron Kindred, of Atlanta.