Nature’s Kidneys: A review of 35 Years of USDA Wetland Restoration – farmdoc daily

Report on the Efficacy of U.S. Wetland Restoration Programs and Their Contribution to Sustainable Development Goals

A recent analysis of three decades of government-supported wetland restoration in the United States, primarily through the Wetland Reserve Program (WRP), reveals significant contributions to environmental quality, economic stability, and community resilience. These outcomes directly align with several key United Nations Sustainable Development Goals (SDGs), particularly those concerning water, ecosystems, and sustainable communities.

Programmatic Framework and Objectives

Established under the 1985 Food Security Act and the 1990 Farm Bill, and later integrated into the Agricultural Conservation Easement Program (ACEP) in 2014, these initiatives were designed to discourage the conversion of wetlands to cropland and to restore previously converted lands. The program operates through a system of conservation easements.

• Mechanism: Landowners voluntarily enter into easement contracts, agreeing to cease all agricultural and forestry practices on the designated land.
• Compensation: In return, they receive a payment, typically averaging $2,700 per acre, while retaining land ownership.
• Restoration: The USDA National Resources and Conservation Service undertakes the physical restoration, which includes planting native species, removing drainage tiles, and constructing berms at an average cost of $650 per acre.

Analysis of Key Findings and Alignment with Sustainable Development Goals

The first large-scale empirical analysis of the program’s impact demonstrates substantial benefits, particularly in the Mississippi River Basin. These findings underscore the program’s role as an effective tool for achieving multiple SDGs.

SDG 6: Clean Water and Sanitation

The report highlights the critical role of restored wetlands in improving water quality, directly contributing to SDG Target 6.3, which aims to reduce pollution and improve ambient water quality.

1. Nutrient Filtration: Restored wetlands function as natural filters (“nature’s kidneys”), significantly reducing nitrogen concentrations in surface water.
2. Quantifiable Impact: The first restoration in a subwatershed was found to decrease ammonia concentration by 0.08 mg/L (a 62% reduction from the mean) and total Kjeldahl nitrogen (TKN) by 0.20 mg/L (a 37% reduction). Subsequent restorations continued to yield measurable improvements.
3. Economic Viability: By reducing nitrogen loads, the program lowers the cost for public water systems to meet the standards of the Safe Drinking Water Act. In high-nitrogen areas, the initial investment in a 100-acre restoration can be paid back in approximately 20 years through savings in water treatment costs, supporting SDG Target 6.1 for safe and affordable drinking water.

SDG 14 & SDG 15: Life Below Water and Life on Land

The program’s success in nutrient reduction and habitat restoration directly supports the protection of both aquatic and terrestrial ecosystems.

• SDG 15 (Life on Land): The core activity of restoring wetlands to their natural state is a direct contribution to Target 15.1, which calls for the conservation and restoration of freshwater ecosystems. The median project size of 100 acres demonstrates that even modest projects can have a significant ecological impact.
• SDG 14 (Life Below Water): By reducing nutrient runoff from agricultural landscapes in the Mississippi River Basin, the program helps mitigate a primary source of pollution affecting downstream marine ecosystems, such as the Gulf of Mexico. This aligns with Target 14.1 to prevent and significantly reduce marine pollution from land-based activities.

SDG 2, SDG 11 & SDG 13: Sustainable Agriculture, Communities, and Climate Action

Beyond water quality, wetland restoration provides co-benefits that enhance agricultural sustainability, community resilience, and climate adaptation.

1. Agricultural Resilience (SDG 2): Restored wetlands act as natural sponges, absorbing excess water. This has been shown to increase crop yields and reduce the risk of “prevent plant” insurance claims on surrounding agricultural fields, contributing to Target 2.4 for sustainable food production systems.
2. Community Resilience (SDG 11): The water absorption capacity of wetlands reduces flood risk in downstream communities, directly supporting Target 11.5 to reduce losses caused by water-related disasters.
3. Economic and Social Benefits (SDG 11): The program strengthens local economies through reduced public expenditure on water treatment and flood damage. Furthermore, it creates recreational opportunities like fishing and hunting, enhancing the social fabric and legacy value of the land for families.

Conclusion

The evaluation of USDA-funded wetland restoration programs confirms their effectiveness in achieving stated conservation goals. The programs represent a cost-effective use of public funds that generates a wide array of benefits. By improving water quality, restoring vital ecosystems, mitigating flood risks, and strengthening local economies, federal support for wetland restoration serves as a powerful, multi-faceted strategy for advancing the Sustainable Development Goals in the United States.

Analysis of Sustainable Development Goals (SDGs) in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

1. SDG 6: Clean Water and Sanitation

   The article’s primary focus is on improving water quality through wetland restoration. It details how the Wetland Reserve Program (WRP) significantly reduces nitrogen concentrations in surface waters, directly contributing to cleaner water. The text states, “We find wetland easements have significantly reduced nitrogen concentration in surface water across the Mississippi River Basin.” It also links water quality to public health and economic savings by discussing the costs for public water systems to remove nitrogen to meet Safe Drinking Water Act standards.

2. SDG 15: Life on Land

   The article is fundamentally about the restoration of terrestrial and inland freshwater ecosystems. The entire analysis revolves around the “impact of three decades of government-supported wetland restoration.” By restoring converted wetlands, the program directly addresses the protection and restoration of vital ecosystems, as described in the article: “USDA National Resources and Conservation Service staff restore the land to its natural wetland condition by planting native species, removing tiling, and building berms.”

3. SDG 14: Life Below Water

   Although the study focuses on inland surface waters, its implications directly connect to marine ecosystems. The article analyzes nutrient reduction in the Mississippi River Basin. Nutrient pollution, particularly nitrogen, from this basin is a primary cause of the hypoxic “dead zone” in the Gulf of Mexico. By demonstrating a reduction in nitrogen loads, the wetland restoration efforts contribute to mitigating land-based pollution affecting marine environments.

4. SDG 11: Sustainable Cities and Communities

   The article connects wetland restoration to community resilience against water-related disasters. It explicitly mentions that “Wetlands also reduce the flood insurance claims in downstream communities,” citing previous research. This highlights the role of natural infrastructure in protecting human settlements from flooding, a key aspect of sustainable and resilient communities.

5. SDG 8: Decent Work and Economic Growth

   The economic benefits of wetland restoration are a key theme. The article argues that the program is a “cost-effective way to strengthen local economies in the Mississippi River Basin.” It quantifies this by estimating the cost savings for public water systems that would otherwise have to pay for expensive nitrogen removal. The analysis shows that “the time to pay back the initial expenditure… is only twenty years,” making it a sound public investment that supports local economies.

2. What specific targets under those SDGs can be identified based on the article’s content?

• Target 6.3: Improve water quality by reducing pollution

  The article directly addresses this target by quantifying the reduction of pollutants in surface water. The study’s main finding is that wetland restoration projects “decreased ammonia concentration by 0.08 milligrams per liter (mg/L)” and “TKN decreased by 0.20 mg/L.” This demonstrates a direct effort to improve water quality by filtering nitrogen, a major pollutant from agricultural runoff.

• Target 6.6: Protect and restore water-related ecosystems

  The article is an evaluation of a program specifically designed to achieve this target. The Wetland Reserve Program (WRP) and its successor, the Agricultural Conservation Easement Program (ACEP), are government initiatives that fund the “restoration of wetlands.” The article analyzes the impact of restoring these critical water-related ecosystems over three decades.

• Target 15.1: Ensure the conservation, restoration and sustainable use of terrestrial and inland freshwater ecosystems

  This target is central to the article. The program under review focuses on restoring “farmed or converted wetland or a riparian area linking protected wetlands.” This is a clear example of restoring inland freshwater ecosystems (wetlands) that have been degraded by agricultural use, directly aligning with the goal of restoration and conservation.

• Target 14.1: Prevent and significantly reduce marine pollution of all kinds, in particular from land-based activities, including… nutrient pollution

  The article’s focus on reducing nitrogen loads in the Mississippi River Basin is a direct action against land-based nutrient pollution. The text states, “Wetlands are likened to ‘nature’s kidneys’ because native wetland plants facilitate the nitrogen cycle and filter nitrogen from surface water.” By filtering this nitrogen, the program helps reduce the nutrient load that eventually flows into the Gulf of Mexico, addressing the root cause of marine nutrient pollution.

• Target 11.5: Significantly reduce… direct economic losses… caused by disasters, including water-related disasters

  The article supports this target by citing research that shows a direct economic benefit from flood mitigation. It states, “Wetlands also reduce the flood insurance claims in downstream communities,” which is a direct measure of reducing economic losses from water-related disasters like floods.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

• Indicator for Target 6.3: Concentration of pollutants in water

  The article provides precise, quantitative indicators for measuring water quality improvement. It measures the change in the concentration of two forms of nitrogen:

  • Ammonia concentration, which decreased by “0.08 milligrams per liter (mg/L).”
  • Total Kjeldahl nitrogen (TKN) concentration, which decreased by “0.20 mg/L.”

• Indicator for Targets 6.6 and 15.1: Extent of restored ecosystems

  The article uses the acreage of restored wetlands as a key indicator of progress. It mentions that a “100% increase in restored wetland acres in a subwatershed” leads to further water quality improvements and notes that “the median project in our sample was only 100 acres.” The total acreage under the WRP/ACEP serves as a direct measure of the extent of restored water-related ecosystems.

• Indicator for Target 11.5: Reduction in economic losses from disasters

  An indicator is explicitly mentioned from a cited study: the “reduc[tion] in flood insurance claims in downstream communities.” This provides a financial metric to quantify the disaster risk reduction benefits of wetland restoration.

• Indicator for Economic Cost-Effectiveness (SDG 8): Cost-benefit analysis and payback period

  The article implies an indicator for economic viability by calculating the cost-effectiveness of the restoration program. It estimates the “cost savings of a 100-acre wetland restoration” for public water systems and calculates a payback period: “the time to pay back the initial expenditure… is only twenty years.” This serves as a powerful indicator of the program’s economic sustainability.

4. Summary Table of SDGs, Targets, and Indicators

Source: farmdocdaily.illinois.edu