Even assuming that the “significant nexus” test from Justice Kennedy’s concurring opinion in Rapanos defines waters of the United States subject to Clean Water Act jurisdiction, the question remains what establishes a significant nexus.  In a decision earlier this week, the 4^th Circuit Court of Appeals provided some important guidance in answering this question.  The news is good for EPA and the Corps, not so good for developers.

The Court laid out four general precepts that apply to all cases:

• Either qualitative or quantitative evidence may demonstration jurisdiction.  Here, the Court rejected the developer’s argument that, because the project involved only a tiny percentage of the watershed, the nexus simply could not be “significant” to the watershed.

•  Expert evidence that the nexus is not “statistically significant” to the watershed “sets the bar too high, as purely qualitative evidence may satisfy the significant nexus test.”

• While a court will assess the various different wetlands functions, “the ultimate inquiry is whether the collective effect of these functions is significant.”

• Finally, since the purpose of the CWA is both to “restore and maintain” the nation’s waters, in a permitting context:

The Corps exercises its jurisdiction to prevent damage and thus cannot be expected to present evidence of the actual ecological impact of the wetlands on downstream waters.

The facts are too detailed for blog discussion.  The geographic nexus was this:  The project involved 4.8 acres of a 448 acre wetland.  The wetlands are adjacent to a 2,500 foot man-made ditch, which itself connects to the Saint Brides Ditch, which joins a small tributary, which ultimately reaches the Northwest River, seven miles from the wetlands.  Sounds attenuated, no?

The court found the following two factors sufficient to demonstrate the required significant nexus:

1.  The ACOE actually obtained some flow data and the Court found that the Corps’ determination of a hydraulic connection was not arbitrary and capricious.

2.  The Corps’ found that the Northwest River has low dissolved oxygen levels and that the wetlands at issue trap nitrogen, which could otherwise worsen the problem.

QED.  The bottom line is that, as long as they do their job, EPA and the Corps are going to win most of these cases.