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Wetlands at Risk: Imperiled Treasures
How a Supreme Court Decision Jeopardizes Millions of Acres of Waters and Wetlands.

Contents page


America's wetlands are in danger. Thirty years after passage of the Clean Water Act, wetlands continue to be drained, filled and polluted at an alarming rate. So-called "isolated wetlands" are in particular peril, due in great measure to a recent Supreme Court decision potentially jeopardizing federal Clean Water Act protections for millions of acres of waters and wetlands.

Wetlands perform several vital functions in the environment. Among other things, they filter pollutants from water, provide critical habitat for a variety of species and mitigate flood damage. Recognizing these important functions, Congress included protections for wetlands in the 1972 Clean Water Act. But in January 2001, the U.S. Supreme Court issued a ruling, Solid Waste Agency of Northern Cook County (SWANCC) v. U.S. Army Corps of Engineers, that could significantly narrow the scope of the act's protection of wetlands. Although the scope of the Court's ruling is not completely clear, it has been read by some to exclude waters determined to be "isolated" from protection under the Clean Water Act.

In application, the ruling has created both confusion and environmental peril because it leaves open to interpretation the question of which wetlands are in fact "isolated."

The issue is a matter of considerable debate, in part because the term "isolated" has no real grounding in science. Researchers and scientists recognize the complex web of connections between seemingly separate or "isolated" wetlands and other waters: they are often connected by water overflow or by groundwater; and they frequently support the same species but during different stages of their life cycles. In addition, so-called "isolated" wetlands, such as prairie potholes, absorb floodwaters and filter pesticides and other pollutants, protecting downstream tributaries, rivers, and wetlands. In short, seemingly "isolated" wetlands are critically necessary to the healthy functioning of the overall ecosystem.

The SWANCC Decision

In the past, under the Clean Water Act, property owners had to apply for a permit from the Army Corps of Engineers before destroying isolated wetlands. This federal jurisdiction was based in part on the Migratory Bird Rule, which protects habitat used by migrating birds. But on January 9, 2001, in Solid Waste Agency of Northern Cook County (SWANCC) v. U.S. Army Corps of Engineers, the Supreme Court ruled that the Migratory Bird Rule could not be used as the sole basis for federal regulation of "isolated" waters.

In the public policy arena, however, as much as 20 to 30 percent of America's wetlands might eventually be deemed "isolated" by the executive branch or by the courts because they will apply an unscientific standard: the absence of a direct surface connection to other bodies of water.

Unless Congress takes action to reassert federal protection, or until individual states take action, decisions about which wetlands are to be protected will be made by the Environmental Protection Agency, the Army Corps of Engineers and the courts, attempting to interpret the Supreme Court's decision. The predictable result is that vast wetland areas will be destroyed, potentially devastating plant and animal life, including a range of migratory birds, increasing the risk of flood damage for populated communities, diminishing wetland-filtration of polluted waters and more. Indeed, in the short time since the SWANCC decision, this wetland loss has already begun to occur.

As the pages that follow illustrate, "isolated" wetlands encompass a rich variety of marshland and small pools. They may be permanent or temporary, reappearing from season to season or year to year, depending on precipitation. Because many are small or exist only for a short period each year, their importance is often not appreciated by policymakers and the public. Indeed, developers frequently target isolated wetlands for commercial projects, despite their environmental importance. The truth is that isolated wetlands play the same vital roles in the environment as other wetlands:

  • Curbing damage from floods. Every year in the United States, floods cause approximately 200 deaths and some $3 billion in property damage.1 Wetlands help curb this loss by absorbing flood waters and impeding the rush of storm runoff, allowing for a slower discharge of water flow.

  • Replenishing water supplies. Wetlands help replenish the drinking water supplies on which communities depend. For example, in west Texas, the Ogallala aquifer is recharged by thousands of scattered wetlands called "playa lakes."

  • Improving water quality. Dubbed the "kidneys" of the landscape, wetlands remove excess nutrients, toxic materials and sediments from the water that flows through them. "Restoring just one percent of a watershed's area to appropriately located wetlands has the potential to reduce polluted runoff of nitrates and herbicides by up to 50 percent....[S]mall wetlands are at least as effective as the same acreage in a larger wetland," according to one expert.2

  • Providing wildlife habitat and ensuring biodiversity. Wetlands are crucial stopovers for millions of migrating waterfowl and shorebirds and provide food and cover for breeding and nesting. Without prairie potholes, the majority of ducks in the mid-continental United States would be at risk. According to the U.S. Environmental Protection Agency, 43 percent of federally threatened and endangered species, such as the whooping crane, rely on wetlands for their survival.

    Temporary or seasonal isolated wetlands are critical to the survival of vulnerable amphibian populations. Juvenile frogs, toads and salamanders depend on small wetlands as a haven from fish predation. The loss of small wetlands can wipe out whole populations of amphibians. Small wetlands also host diverse and unusual plant communities that could prove important to efforts to develop new medicines and other botanical products. But the plants are disappearing before even being studied.

  • Recreation, food and aesthetic enjoyment. Each year, millions of Americans visit wetland areas to hunt, canoe and birdwatch. Moreover, wetlands are living laboratories for students of all ages. Researchers have found that ecological wellbeing depends not only on preserving the total acreage of wetlands, but on maintaining a mosaic of different types and sizes of wetlands that together perform these complex and critical functions. Isolated wetlands are crucial pieces of this mosaic. Unless political leaders act quickly to protect them, however, they may be lost forever. Wetlands play a vital role in the environment in all regions of the nation. The pages that follow offer a survey of many of the unique and valuable types of wetlands that are at greater risk of destruction due to the SWANCC decision and a sampling of the plant and animal life put at risk if these wetlands are lost.

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1. Robinson, Ann. 1995. Small and seasonal does not mean insignificant: Why it's worth standing up for tiny and temporary wetlands. Journal of Soil and Water Conservation November/December: 588.

2. Robinson, p. 588.

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