Yesterday, we blogged about the EPA and Corps’ proposed rule defining what waters fall under federal jurisdiction. In a leaked draft, EPA was seen to have been contemplating explicitly excluding puddles from regulation, but, in the end, didn’t do so. EPA provided an explanation as to why, but the rule is so broad, we think EPA’s explanation may not be completely relevant. In other words, because the rule is so broad, many puddles actually might fall under federal jurisdiction. The reason is the host of new definitions proposed by EPA. Previously undefined terms like tributary, neighboring, and floodplain are all now defined, and in a way that creates a web of federal jurisdiction. Here’s how: 

1. The rule starts with an initial list of jurisdictional areas, which includes (a) waters that are, have been, or could be used in interstate commerce, (b) interstate waters, and (c) the territorial seas. 
2. The rule then adds to this list all tributaries of these waters. Tributary gets defined for the first time as any feature with a bed and bank that contributes flow to any water on the initial list. Many features, like dry arroyos and mountain channels, have bed and bank even though they only flow when it rains or the snow melts:
3. The rule then continues, adding to the list of jurisdictional waters all waters that are adjacent to the initial waters and their tributaries. Adjacent is “bordering, contiguous or neighboring.”
4. EPA then defines neighboring for the first time to include any water in the floodplain or a riparian area of the initial waters and their tributaries. These also get new definitions. Floodplain is an area along a water, formed by sediment deposition and inundated during moderate to high flows. Riparian area is one bordering any water where surface or groundwater “directly influence the ecological processes and plant and animal community structure in that area.”

The end result is that areas are jurisdictional, as far upstream as one can find a bed and bank, and as far outward from that bed and bank as the area “directly influences” the area’s ecology or is formed by sediment and gets inundation from high flows. That is a lot of area. To give you a sense of the potential breadth of areas “subject to inundation,” this map shows in blue the flooding along the Mississippi River in 2011 and the counties/parishes at risk of significant flooding:

Fully one-third of Arkansas was covered. One half of the counties in Illinois were at risk.

This brings us back to puddles. In the proposal’s preamble, EPA says it removed puddles from the “not jurisdictional” list for clarity, not to imply they are jurisdictional.

Some puddles, it says, are not jurisdictional. The language of the rule, however, suggests that puddles are arguably jurisdictional if they are in floodplains or riparian areas. The fact that puddles aren’t always wet may not be decisive: EPA considers streams which flow only when it rains or snow melts to be jurisdictional and identifies dry features as “water”:

We’re not saying that EPA would take the position that puddles are jurisdictional – our only point is that the language of the proposed rule is so broad that it could. And we haven’t even started on the “significant nexus” test.

This is the second in a series of posts regarding EPA’s proposed rule redefining “waters of the United States” under the Clean Water Act.

For part one, click here.

For part three, click here.

For part four, click here.

For part five, click here.

For part six, click here.

Photo credits, from top: Photo of the Las Cruces Arroyo from Wikipedia. Mississippi River map from the US Census Bureau. Photo of a wetland from the Arid West Region Regional Supplement to the Corps’ Wetland Delineation Manual.