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How significant does a nexus have to be

Swamp Stomp

Volume 14, Issue 2

How significant does a nexus have to be?

The issue of what is and is not a significant nexus is center to the new EPA Clean Water Act (CWA) rules. In order for a wetland or other water body to be jurisdictional under the Act it must have this connection to a navigable waterway. The problem is what is a significant nexus?

This whole issue arose as a result of the Rapanos and Carabell Supreme Court case in 2006. Justice Kennedy coined the term “Significant Nexus” in his lone opinion. It paralleled the plurality’s two-part test involving the receiving waters that have a relatively permanent flow and whether those waters have a continuous surface connection to navigable-in-fact waters. However he went a step beyond the physical connection and introduced a water quality connection.

One other factor is that the plurality Justices did not feel that dredge or fill material normally washes downstream. Both Justice Kennedy and Justice Stevens in his dissent, made it clear that this assertion simply is untrue. Justice Kennedy stated that the discharge of dredged and fill material should be treated the same as the discharge of any other pollutant under the Clean Water Act. Justice Kennedy further stated that the intent of the CWA is to maintain wetlands that provide filtering and other attributes to benefit adjacent bodies of water.

So the problem remains. What is a significant nexus?

There are two types of waters we need to assess. The first one is easy. Simply ask the question, is there a physical connection to a downstream navigable waterway? If the answer is yes, it is jurisdictional.

Now there are many ways a wetland could be connected. But for this analysis we are more or less limited to surface and shallow sub surface connections of a foot or less. This has been the general rule of thumb since about 2007.

With the new EPA rules there is discussion on unidirectional and bidirectional flow patterns. This further demonstrates the connection to the navigable waterway. What is new is the introduction of non-wetland areas that have bi-directional water patterns and connections to downstream navigable waters. By default, these areas are connected and therefore jurisdictional. Floodplains are an example of this. By the way, this is new.

The remaining waters are either adjacent wetlands that do not have obvious physical connections. These may also be isolated wetlands. Adjacent wetlands by rule are jurisdictional. Isolated wetlands need to have a significant nexus.

So what is a significant nexus?

If there is no physical connection, you are asked to assess the chemical and biological connectivity to the downstream waters. This was the subject of the recent EPA “Connectivity of Streams and Wetlands to Downstream Waters”, report that described in great detail how all waters are connected to all other waters. I believe you would have to have a project on the moon in order to not satisfy the connectivity of one water to another based upon the EPA report.


However, that only addresses the concept of nexus. The issue is significant. Pardon the pun.

Really the issue is the significance of the connection. If the connection from one water body to another is altered, can you prove and quantify degradation to the water quality?

The biggest problem that was identified with the EPA report is the lack of discernment of the significance of one connection versus another. The entire report’s premise was to reduce the number of case by case studies on projects. The idea was that the water body is connected therefore it is jurisdictional. However, Justice Kennedy used the word significant. That remains undefined. Neither the new rules nor the recent EPA report quantify what is significant.

So what is significant?

That is left for you to decide. Is there a significant loss of water quality that would result from your project?

There is also the issue of whether this loss of water quality going to affect commerce? It is not just that the water quality is degraded, but rather that there is an interstate or international economic loss as a result. Without this commerce connection there can be no jurisdiction thanks to Article 1, Section 8 of the United States Constitution.

One last thought. What if you project improves the downstream economy? Would that still be jurisdictional as Justice Kennedy’s Significant Nexus only speaks to degradation of the downstream water? Just asking.

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