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Intermittent Streams under the New WOTUS Rule


The new WOTUS rule, if it goes into effect, will redefine in a significant way what is covered by the CWA. The EPA has promoted this new rule as an improvement in that it will be easier to implement. Let’s look at the claim as it applies to intermittent streams.


Under the 2015 rule, all intermittent streams are jurisdictional. You may not like that result, but it’s very easy to know if they’re covered. Under the 2008 Rapanos Guidance, which is currently in place, intermittent streams must be analyzed case-by-case to determine whether there is a significant nexus to downstream waters. That is a very time-consuming and complex analysis.


The new rule covers intermittent streams that contribute flow in a typical year to TNWs. That seems simple enough, but there’s a lot to unpack given how EPA and the Corps have loaded so much into the definitions. Start with the definition of tributary, which requires “surface water flow to [a TNW] in a typical year . . . A tributary must be perennial or intermittent in a typical year.” 33 C.F.R. 328.3(c)(12). And note the tributary includes certain types of ditches, but not all ditches. Id.


Then turn to “typical year” which means “when precipitation and other climatic variables are within the normal periodic range (e.g., seasonally, annually) for the geographic area of the applicable aquatic resource based on a rolling thirty-year period.” 33 C.F.R. 328.3(c)(13). How is a farmer going to know the answer to that?


Then look at “intermittent stream,” which means “surface water flowing continuously during certain times of the year and more than in direct response to precipitation (e.g., seasonally when the groundwater table is elevated or when snowpack melts).” 33 C.F.R. 328.3(c)(5).

Which brings us to “snowpack,” which is defined as “layers of snow that accumulate over extended periods of time in certain geographic regions or at high elevation (e.g., in northern climes or mountainous regions).” 33 C.F.R. 328.3(c)(10).


My question is, how is a farmer supposed to know whether his stream is intermittent without a professional opinion from a geohydrologist? I see all kinds of fights over whether the stream is flowing “in direct response to precipitation.” How will someone know whether the flow is affected by a groundwater component without a case-by-case study, which could involve months of data collection in the spring to determine base flows. What about seasonal variability in groundwater levels? I’m sure the EPA and the Corps will end up issuing guidance on this, which will end up looking like the Rapanos Guidance, which only lawyers and wetlands specialists can understand.


If you're a fan of reduced federal jurisdiction, this is a great rule. If you're hoping for simplicity in the application, you'll be disappointed.

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