Peterson Chelsea M, Nieset Julie E, Monson Jessica L, Pociask Geoffrey E, Wilm Brian W, Marcum Paul B, Matthews Jeffrey W
Department of Natural Resources and Environmental Sciences, University of Illinois Urbana-Champaign, Urbana, IL, USA.
Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, IL, USA.
J Environ Manage. 2025 Sep;392:126931. doi: 10.1016/j.jenvman.2025.126931. Epub 2025 Aug 11.
The 2023 Sackett v. EPA US Supreme Court ruling narrowed Clean Water Act (CWA) protection for wetlands by requiring a "continuous surface connection" to "waters of the United States" (WOTUS). As most states have limited or no legal wetland protections beyond the CWA, the ruling has left millions of US wetlands, with $11.2-$67.0 billion in flood-control benefits, vulnerable to impacts. To assess the ruling's implications for Illinois, we integrated geospatial datasets to identify state wetlands that could be federally non-jurisdictional (non-WOTUS) across 96 policy scenarios with different requirements for wetland spatial and temporal connectivity to relatively permanent waters (RPWs). Although agency requirements for wetland flood frequency were the largest source of policy uncertainty, we estimated that up to 286,342 ha (72.1 %) of remaining state wetland area could be non-WOTUS if wetlands must have at least seasonal flooding for CWA protection. Despite predicting that up to 227,642 ha (79.5 %) of non-WOTUS area is unprotected, we estimated that more non-WOTUS area is protected than previous studies by accounting for county-level regulations. By further evaluating the relationship between unprotected wetland area and risk of climate-driven natural disasters, we found that county-level regulations limit the potential for wetland losses to increase 30-year flood risk in northeastern Illinois. Outside this region, unprotected wetland area has a strong positive correlation with property share at risk of flooding in 30 years and with expected losses in population and building value. Thus, enhancing protections for wetlands that are intermittently dry or geographically isolated from WOTUS could increase the resilience of lower elevation and latitude floodplain communities to climate change.
2023年美国最高法院关于“萨克特诉美国环境保护局案”的裁决，通过要求与“美国水域”（WOTUS）有“连续地表连接”，缩小了《清洁水法》（CWA）对湿地的保护范围。由于大多数州除了《清洁水法》之外，对湿地的法律保护有限或没有保护，该裁决使数百万具有112亿至670亿美元防洪效益的美国湿地容易受到影响。为了评估该裁决对伊利诺伊州的影响，我们整合了地理空间数据集，以确定在96种政策情景下，哪些州内湿地可能不受联邦管辖（非WOTUS），这些情景对湿地与相对永久性水域（RPW）的空间和时间连通性有不同要求。尽管机构对湿地洪水频率的要求是政策不确定性的最大来源，但我们估计，如果湿地必须至少有季节性洪水才能获得《清洁水法》的保护，那么该州剩余湿地面积中高达286,342公顷（72.1%）可能不属于WOTUS。尽管预计多达227,642公顷（79.5%）的非WOTUS区域未受保护，但通过考虑县级法规，我们估计受保护的非WOTUS区域比以前的研究更多。通过进一步评估未受保护湿地面积与气候驱动自然灾害风险之间的关系，我们发现县级法规限制了伊利诺伊州东北部湿地损失增加30年洪水风险的可能性。在该地区以外，未受保护的湿地面积与30年内有洪水风险的财产份额以及人口和建筑价值的预期损失呈强烈正相关。因此，加强对间歇性干燥或在地理上与WOTUS隔离的湿地的保护，可以提高低海拔和低纬度洪泛区社区应对气候变化的复原力。
