The “Significance” of the “Nexus”: Latest (Last?) Precon Decision on Wetlands Jurisdiction

Posted on March 17, 2015 by Margaret (Peggy) N. Strand

In a decision that may end a 13-year battle over wetlands jurisdiction, the Fourth Circuit on March 10 upheld the U.S. Army Corps of Engineers findings that a 4.8 acre wetland had a “significant nexus” to navigable waters under the Clean Water Act. Of importance to future challenges, the court deferred to the Corps’ rather ordinary wetlands evidence, despite contrary evidence from a developer of a proposed planned unit development in Chesapeake, Virginia. 

The Precon case spanned the 2006 Supreme Court decision in Rapanos v. United States, when Justice Kennedy introduced the jurisdictional standard of “significant nexus.”  For a refresher, a “significant nexus” between wetlands and navigable waters exists “if the wetlands, either alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as ‘navigable.’”. For previous posts concerning CWA jurisdiction, see here and here. The Fourth Circuit previously had found a “nexus” between Precon’s 4.8 acre wetland and navigable waters seven miles away and allowed aggregation of the Precon’s 4.8 wetland acres with a region of 448 “similarly situated” wetlands, but remanded for application of the “significant” aspect of Justice Kennedy’s test.

CWA jurisdictional groupies watched the Precon case as among the first to involve evidence demonstrating jurisdiction under the “significant nexus” test and the only decision to be remanded for a showing of “significance.”  Evidence was presented, experts disagreed, and the court deferred to the Corps.  On the key point of “significance,” the decision found neither arbitrary nor capricious the Corps’ findings of water flow. In addition, the court deferred to the Corps’ showing of wetland functions in relation to the navigable water, particularly water quality (dissolved oxygen) impairments to the Northwest River, which are reduced by the carbon sequestration of retained organic matter by the aggregated wetlands. The court also found credible the Corps’ qualitative evidence of habitat use by common species (deer, squirrels, amphibians).

The take-away:  If a “nexus” is “significant” based on a showing of general relationship of wetland functions to downstream receiving water impairments and common wildlife (wetland and non-wetland) usage, it is hard to imagine a wetland failing to be held jurisdictional when aggregation is allowed.  Counsel for Precon indicates it will seek en banc rehearing and may seek certiorari, so there may be yet another chapter to this saga.