Hazardous and Solid Waste

Bill Halts Guidance on ‘Federally Regulated Waters’

Following are key points made in the draft guidance in three critical areas–significant nexus, tributaries, and adjacent wetlands.

Significant Nexus

To evaluate the presence or absence of a significant nexus, the agencies intend, as a general matter, to consider:

•              Waters similarly situated with waters of the same resource type, specifically tributaries, adjacent wetlands, or other waters that are in close physical proximity to traditional navigable waters, interstate waters, or their jurisdictional tributaries (proximate other waters).
•              Waters in the region if they fall within the same watershed.
•              Waters that alone or in combination with other similarly situated waters in the same watershed have an effect on the chemical, physical, or biological integrity of traditional navigable waters or interstate waters that is more than “speculative or insubstantial.”

Justice Kennedy provides guidance about the nature of the nexus when he says that waters are not jurisdictional when their effects on the physical, chemical, or biological integrity of downstream traditional navigable waters are speculative or insubstantial.  Rather, a significant nexus includes having a predictable or observable chemical, physical, or biological functional relationship between the similarly situated waters and the traditional navigable or interstate water.

According to the guidance, the effects of one water body on another can be determined by measures such as the capacity of water to carry pollutants downstream; the extent to which the waters reduce the amount of pollutants or flood waters that would otherwise enter traditional navigable or interstate waters; and the extent to which the waters perform physical functions related to the maintenance of downstream water quality, such as sediment trapping.

In terms of expanding the definition of “regulated waters,” the guidance notes that it is “not appropriate to determine significant nexus based solely on any specific threshold of distance (for example, between a tributary and the traditional navigable water).” Thus, a tributary can have a significant nexus with a traditional or interstate water body even if the two are separated by a substantial distance.

The guidance emphasizes that agency staff are not required to identify or evaluate every similarly situated water in a watershed to conclude that a significant nexus exists.  “In many cases,” the agencies state, “scientifically credible (e.g., peer reviewed) literature on the functions and effects of similarly situated waters generally will be sufficient, along with site-specific information for the water for which a determination is being conducted, to support a significant nexus jurisdictional determination.”  Staff are advised to evaluate as many waters of the same type as is necessary to support and document the presence or absence of a significant nexus for that type of water (e.g., adjacent wetland, tributary, or proximate other water).

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A water is a tributary if it contributes flow to a traditional navigable or interstate water either directly or indirectly by means of other tributaries.  A tributary can be natural, man-altered, or man-made.  Erosional features such as gullies and rills are not considered tributaries; neither are nontidal ditches (including roadside and agricultural ditches) unless they have a bed, bank, and ordinary high water mark (OHWM).

The guidance applies both the plurality decision in Rapanos and Justice Kennedy’s significant nexus opinion to assert jurisdiction over tributaries.

The plurality decision states that relatively permanent waters can be found jurisdictional without making a significant nexus finding.  Here, a nonnavigable tributary is jurisdictional if it is connected directly or indirectly through other tributaries to a downstream traditional navigable water, and flow in the tributary, except for drought years, is at least seasonal.

Waters that are not relatively permanent will be evaluated under the Kennedy standard.  If it can be demonstrated that the tributary has a bed and bank, and an OHWM is part of a tributary system to a traditional navigable water or an interstate water, and, therefore, can transport pollutants, flood waters, or other materials to a traditional navigable or interstate water, the agencies would generally expect that the tributary along with the other tributaries in the watershed (the similarly situated waters) can be demonstrated to have a significant nexus with the downstream traditional navigable water or interstate water. The guidance advises that tributaries that are not relatively permanent be subjected to a site-specific analysis to confirm that a significant nexus exists (i.e., identify the potential for the tributary to transport pollutants to the navigable water).

As seen here, the guidance provides substantial tools to demonstrate that tributaries are jurisdictional.

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Adjacent Wetlands

Similar to tributaries, the guidance defines “regulated adjacent wetlands” under either the Rapanos plurality standard or the Kennedy standard.

Under the plurality opinion, the wetland is adjacent if there is a continuous surface connection to the downstream water.  The presence of water in the connection is not required at all times to establish adjacency.

Under the Kennedy standard, a wetland is jurisdictional:

•              If it is physically separated from the jurisdictional waters by man-made dikes or barriers, natural river berms, beach dunes, and the like, or
•              If the wetland is “reasonably close” to the jurisdictional water.  One test to determine reasonable closeness is demonstrating an ecological interconnection.  For example, if resident aquatic species (e.g., amphibians, aquatic turtles, fish, or ducks) rely on both the wetland and the jurisdictional water body for all or part of their life cycles, this may demonstrate that the wetland is neighboring and thus adjacent.  The agencies add that they recognize that as the distance between the wetland and the jurisdictional water increases, the potential ecological interconnection between them is likely to decrease.

The guidance also points out that all wetlands within a wetland mosaic generally act as a single ecological unit.  A wetland mosaic refers to a landscape where wetland and nonwetland components are too numerous and closely associated to be appropriately delineated or mapped separately.  Under such circumstances, the guidance does not require that field staff assess every wetland in a watershed to establish a significant nexus relationship. “As with tributaries, field staff may utilize a smaller area for a significant nexus analysis where this is sufficient to establish the presence or absence of a significant nexus for adjacent wetlands within the watershed as a whole,” according to the guidance.

In the final analysis, the draft provides a wide array of tools to affirm jurisdiction over types of waters that both critics and supporters of the document assert would be designated nonjurisdictional under previous guidance.