In Rapanos v. United States, 126 S. Ct. 2208 (2006), the United States Supreme Court struck down an interpretation by the U.S. Army Corps of Engineers and the U.S. Environmental Protection Agency of their jurisdiction to regulate wetlands under the Clean Water Act. Here is how Justice Scalia described the agencies' interpretation:

In the last three decades, the Corps and the Environmental Protection Agency (EPA) have interpreted their jurisdiction over “the waters of the United States” to cover 270-to-300 million acres of swampy lands in the United States —including half of Alaska and an area the size of California in the lower 48 States. And that was just the beginning. The Corps has also asserted jurisdiction over virtually any parcel of land containing a channel or conduit—whether man-made or natural, broad or narrow, permanent or ephemeral—through which rainwater or drainage may occasionally or intermittently flow. On this view, the federally regulated “waters of the United States” include storm drains, roadside ditches, ripples of sand in the desert that may contain water once a year, and lands that are covered by floodwaters once every 100 years. Because they include the land containing storm sewers and desert washes, the statutory “waters of the United States” engulf entire cities and immense arid wastelands. In fact, the entire land area of the United States lies in some drainage basin, and an endless network of visible channels furrows the entire surface, containing water ephemerally wherever the rain falls. Any plot of land containing such a channel may potentially be regulated as a “water of the United States.”

The Supreme Court rejected this expansive interpretation and remanded the case for further deliberation. Unfortunately, the Court gave no clear guidance about what the new standard ought to be. Instead, the Court issued five separate opinions (one plurality opinion, two concurring opinions, and two dissenting opinions) that created substantial confusion about what exactly the Court had done.

On June 5, 2007, the EPA and the Corps issued long-awaited guidance, specifying how they would proceed in the wake of the Rapanos decisions. As a practical matter, the agencies have responded to the confusion created by the multiple Rapanos decisions by largely re-affirming their prior interpretation. The Guidance addresses three different categories of wetlands, from those most obviously included within the agencies' jurisdiction to those least obviously included.

  1. Traditional navigable waters and their adjacent wetlands. The Guidance provides that the agencies will continue to assert jurisdiction over traditional navigable waters and to wetlands "adjacent to" such waters. For purposes of the Guidance, "adjacent to" means "bordering, contiguous, or neighboring," but an "adjacent" wetland need not have a "continuous surface connection."
  2. Relatively permanent non-navigable tributaries of traditional navigable waters and wetlands with a continuous surface connection to such tributaries. The Guidance provides that the agencies will assert jurisdiction over "relatively permanent" tributaries to navigable waters, so long as the tributaries typically flow year-round, or have continuous flow at least seasonally (three months or more). The agencies will also assert jurisdiction over adjacent wetlands that are not separated from the "relatively permanent" tributary by uplands, a berm, a dike, or similar features.
  3. "Certain adjacent wetlands and non-navigable tributaries that are not "relatively permanent". The Guidance provides that the agencies will assert jurisdiction over non-navigable, not relatively permanent tributaries and their adjacent wetlands, so long as they have a "significant nexus" to a traditional navigable water. The "sufficient nexus" test depends upon a site-specific consideration of multiple factors, including (1) the volume and duration of the flow; (2) the proximity to navigable waters; (3) the size of the watershed; (4) annual rainfall; (5) annual winter snow pack; (6) the potential of tributaries to carry pollutants and flood waters to navigable waters; (7) the provision of an aquatic habitat that might support a navigable water; (8) the potential of wetlands to trap and filter pollutants or store flood water; and (9) the maintenance of water quality in navigable waters. The only waters expressly excluded from this category are (1) swales, gullies, and washes characterized by infrequent, short duration flow; and (2) excavated ditches that drain only uplands and do not carry a relatively permanent flow.

The Bottom Line

This Guidance is a disappointment for the regulated community. The agencies have not significantly restricted their jurisdiction to regulate wetlands, nor have they issued clear guidance that would help someone determine whether they need a permit. Despite a Supreme Court decision and a brand new guidance document, little has changed, and legally, the waters are as muddy as ever.