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RESPONSE TO COMMENTS 

“CLEAN WATER ACT JURISDICTION FOLLOWING THE SUPREME 

COURT’S DECISION IN RAPANOS v. UNITED STATES & CARABELL v. 

UNITED STATES GUIDANCE” ISSUED JUNE 5, 2007

On June 5, 2007, the Environmental Protection Agency (EPA) and the U.S. Army 

Corps of Engineers (the Corps) issued guidance, effective immediately, regarding Clean 

Water Act (CWA) jurisdiction following the U.S. Supreme Court’s decision in the 

consolidated cases Rapanos v. United States and Carabell v. United States. The 

agencies accepted public comments on the Rapanos guidance until January 20, 2008. 

The agencies received 66,047 public comments on the Rapanos Guidance (65,765 form 

letters, 282 non-form letters), from States, environmental and conservation organizations, 

regulated entities, industry associations, and the general public. EPA and the Corps have 

reviewed the comments and have revised the guidance in consideration of those 

comments and consistent with our experience implementing the guidance over the past 18 

months. 

 The comments generally addressed four substantive issues and two procedural 

ones. The substantive areas were: the interpretation of the term “significant nexus;” the 

treatment of tributaries; the definition of “relatively permanent waters;” and the scope of 

“traditional navigable waters.” The procedural areas were: the delay in processing 

jurisdictional determinations and the coordination between the two agencies on 

jurisdictional determinations. 

 The agencies also received comments from some on other important issues. One 

of these, the definition of adjacency, which has been an important implementation issue 

for the agencies, is also discussed below. 

Significant Nexus

 

 In Rapanos, Justice Kennedy concluded that wetlands are “waters of the United 

States” “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.’ When, in contrast, wetlands’ 

effects on water quality are speculative or insubstantial, they fall outside the zone fairly 

encompassed by the statutory term ‘navigable waters.’” The agency guidance states that 

the agencies will assess the flow characteristics and functions of the tributary itself, 
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together with the functions performed by any wetlands adjacent to that tributary, to 

determine whether collectively they have a significant nexus with traditional navigable 

waters. 

Comments: 

 

 Environmental and conservation communities commented that the guidance 

interprets the term significant nexus too narrowly. They commented that under the 

Kennedy standard the agencies have the ability to continue to protect wetlands when they 

collectively affect water quality and to apply that protection to similar waterbodies. The 

regulated community commented that significant nexus is interpreted too broadly in the 

guidance. These commenters argued that there needs to be actual data showing impacts 

to integrity of traditional navigable waters (TNWs) to establish a significant nexus. 

States commented that they were concerned about the analytical and data burden of 

making significant nexus determinations consistent with the guidance. Arid states were 

especially concerned that a narrow interpretation leaves many important streams 

unregulated and thus unprotected. 

Response:

 

 The agencies have made no changes to the guidance with respect to significant 

nexus findings. The agencies struck a careful balance when interpreting Justice 

Kennedy’s opinion. The positions articulated by commenters were among those 

considered by the agencies when developing the guidance, and the agencies have decided 

to maintain their interpretation of the term significant nexus for purposes of determining 

when a water is a “water of the United States.” 

Treatment of Tributaries 

 

 The guidance interprets Justice Kennedy’s standard to apply to tributaries as well 

as wetlands. The guidance also clarifies that a tributary includes natural, man-altered, or 

man-made water bodies that carry flow directly or indirectly into a traditional navigable 

water. In addition, for the purposes of the guidance, a tributary is the entire reach of the 

stream that is of the same order (i.e., from the point of confluence, where two lower order 

streams meet to form the tributary, downstream to the point where such tributary enters a 

higher order stream). Under the guidance, the flow characteristics of a particular 

tributary will be evaluated at the farthest downstream limit of such tributary (i.e., the 

point the tributary enters a higher order stream). 

Comments: 

 

 The environmental community commented that Rapanos did not address the 

scope of CWA jurisdiction for tributaries, and they should be jurisdictional categorically. 

The conservation community commented that tributaries should be jurisdictional 

categorically, or, alternatively, any tributary with an ordinary high water mark should be 

presumed to have a significant nexus. The regulated community commented that 
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tributaries are subject to Rapanos. States expressed concern about the loss of jurisdiction 

over tributaries generally. Arid states in particular expressed concerned about ephemeral, 

intermittent and headwater streams that are critical resources in their states. 

 A smaller number of commenters addressed the stream reach concept in the 

guidance. The general consensus among the regulated community was that the concept is 

overly broad in its interpretation and application when determining jurisdiction, and 

many suggested that the concept be abandoned. The environmental community 

commented that the concept limits jurisdiction and is not in keeping with Justice 

Kennedy’s intent. Other commenters recommended the concept be more scientifically or 

ecologically based and that it should take into account a broader watershed approach. A 

few commenters opposed the guidance to assess flow at the farthest downstream limit. 

Some commented thought that this was simply not feasible, while others suggested that 

this was not the most appropriate approach to assessing an entire stream, suggesting that 

the stream flow be assessed where it is most representative of the entire stream. 

Response: 

 

 The agencies have made no changes to the guidance with respect to utilizing 

Justice Kennedy’s standard to determine the jurisdiction of tributaries. The agencies 

struck a careful balance when interpreting Justice Kennedy’s opinion. The positions 

articulated by commenters were among those considered by the agencies when 

developing the guidance, and the agencies have decided to maintain their interpretation of 

the scope of Justice Kennedy’s standard for purposes of determining when a tributary is a 

“water of the United States.” 

 The agencies have made some changes with respect to assessing flow in 

tributaries for purposes of determining whether a tributary is relatively permanent. 

Footnote 24 of the guidance now clarifies that where data indicates the flow regime at the 

downstream limit is not representative of the tributary (e.g., where data indicates the 

tributary is relatively permanent at its downstream limit but not for the majority of its 

length, or vice versa), the flow regime that best characterizes the tributary should be used. 

Definition of Relatively Permanent Waters

 

 For purposes of implementing Justice Scalia’s standard, the guidance interprets 

relatively permanent waters (RPWs) as “waters that typically (e.g., except due to 

drought) flow year-round or waters that have a continuous flow at least seasonally (e.g., 

typically three months).” 

Comments: 

 

 The environmental community commented favorably on the agencies’ approach 

to determining RPWs. The regulated community commented that RPWs should be 

limited to perennial streams or those that flow at least 290 days. The conservation 

community commented that the guidance’s approach to RPWs could inappropriately 
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eliminate jurisdiction over some intermittent streams. They further commented that 

physical indicators, rather than timing of flow, should be used to meet the plurality test. 

Response: 

 

 The agencies have made no changes to the guidance with respect to their 

approach to determining RPWs. The agencies struck a careful balance when interpreting 

Justice Scalia’s opinion. The positions articulated by commenters were among those 

considered by the agencies when developing the guidance, and the agencies have decided 

to maintain their interpretation of the term relatively permanent for purposes of 

determining when a water is a “water of the United States.” However, the agencies have 

provided additional technical guidance in footnote 24 on how to assess flow in a tributary 

to determine whether it is an RPW. 

Traditional Navigable Waters 

 The agencies stated in the guidance that they considered section (a)(1) of their 

regulations defining “waters of the United States” to constitute the “traditional navigable 

waters” (TNWs) for purposes of Clean Water Act jurisdiction (see footnote 20 of the 

guidance and Appendix D of the field instructional manual). 

Comments: 

 

 Environmental and conservation communities commented that TNWs should be 

interpreted as broadly as possible. The regulated community commented that TNWs are 

no broader than Section 10 waters under the Rivers and Harbors Act of 1899 (RHA). 

Response: 

 

 The agencies have made some changes to the guidance to clarify the scope of 

“traditional navigable waters” for purposes of CWA jurisdiction. The agencies have 

edited footnote 20 of the guidance to make even more explicit that they consider Section 

10 waters to be a subset of TNWs. In addition, changes to footnote 20 provide more 

guidance to the field on how to determine if a water is a TNW, including how to 

determine if it is susceptible for use in commercial navigation, including commercial 

water-borne recreation. 

Processing Delay 

 

 To ensure that decisions are made on sound science and a defensible record, the 

guidance instructs Corps districts and EPA regions to document jurisdictional 

determinations (JDs) in a manner consistent with the standards laid out by the opinion. 

Specifically, the guidance indicates the “record shall, to the maximum extent practicable, 

explain the rationale for the determination, disclose the data and information relied upon, 

and, if applicable, explain what data or information received greater or lesser weight, and 

what professional judgment or assumptions were used in reaching the determination.” 
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The agencies issued a number of documents, in conjunction with the Rapanos guidance, 

to assist field staff to make accurate and appropriately documented JD decisions. These 

documents included a field instructional manual, a JD form, and a MOU establishing an 

interagency coordination process with specific deadlines. 

Comments: 

 

 All commenter groups expressed concern regarding delay in finalizing official 

JDs (i.e., “approved JDs”), and implications of that delay for permitting decisions and 

timing of associated projects. Many identified as a source of delay the extent of data and 

analysis required to finalize an approved JD. A number of commenters from the 

regulated community, state departments of transportation, and the conservation 

community recommended that the agencies provide an opportunity to “opt into” 

jurisdiction, allowing project proponents willing to have all aquatic resource impacts 

evaluated and mitigated to move to the permitting process rather than awaiting an 

approved JD. 

Response: 

 

 On June 26, 2008, the Corps of Engineers issued Regulatory Guidance Letter 

(RGL) 08-02, clarifying that project proponents may request a preliminary JD, which is 

based on an “effective presumption of CWA/RHA jurisdiction over all of the wetlands 

and other water bodies at the site.” (See RGL 08-02, paragraph 9a.) Consequently, a 

preliminary JD allows the Corps to proceed to the permitting process rather than waiting 

for an approved JD. RGL 08-02 indicates that, with such preliminary JDs, there is no 

legally binding determination of CWA jurisdiction over the particular water body or 

wetlands in question, but only a presumption of jurisdiction to facilitate permitting. For 

all cases where approved JDs are used, the agencies continue to believe that welldocumented approved JDs are necessary to ensure that decisions are made based on 

sound science and a defensible record, and so the agencies have not modified 

documentation requirements for approved JDs in the guidance.

Coordination Process 

 

 Concurrent with issuance of the Rapanos guidance, the agencies established a 

coordination process for draft approved JDs involving a significant nexus or section 

(a)(3) of the regulatory definition of “waters of the United States.” The June 2007 

coordination process provided specific timeframes for interagency review, and a process 

for field staff to elevate specific JDs to EPA and Corps headquarters for resolution if 

necessary. While the coordination procedures for (a)(3)-related JDs were to continue 

indefinitely unless the agencies agreed to modifications, coordination of significant 

nexus-related JDs was to end after six months unless the agencies agreed to continue. 
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Comments: 

 

 Several commenters from state environmental agencies, environmental 

nonprofits, and the general public emphasized the importance of JD coordination for 

consistent and accurate JDs. Some commenters from the regulated community and state 

departments of transportation indicated that the interagency coordination process caused 

delays and recommended that coordination with EPA be ended altogether. 

Response: 

 

 On January 28, 2008, the Corps indicated that for significant nexus-related JDs, 

the coordination process was being changed to provide a shorter timeframe than was 

established when the guidance was originally issued. Under the new coordination 

process for significant nexus-related JDs, the EPA Region has 15 days to review the draft 

JD, discuss any questions or concerns with the Corps District, and “special case” the JD 

if they feel it is necessary after those discussions. Coordination of (a)(3)-related draft 

JDs remained unchanged. As a result, the Corps continues to provide EPA with all draft 

JDs involving significant nexus or (a)(3) waters. This does not apply to preliminary JDs, 

since these are only used in cases where a project sponsor agrees to a presumption of 

CWA/RHA jurisdiction over all waters on the project site. 

Adjacency

 The guidance states that the agencies will continue to assert jurisdiction over 

wetlands “adjacent” to traditional navigable waters as defined in the agencies’ 

regulations. Under EPA and Corps regulations and as used in this guidance, “adjacent” 

means “bordering, contiguous, or neighboring.” Finding a continuous surface connection 

is not required to establish adjacency under this definition. The Rapanos decision does 

not affect the scope of jurisdiction over wetlands that are adjacent to traditional navigable 

waters because at least five justices agreed that such wetlands are “waters of the United 

States.” 

Comments

 

 Some in the regulated community commented that the automatic regulation of 

nearby wetlands based solely on their adjacency to a traditional navigable water is 

inappropriate. These commenters also requested that the definition of “adjacent” be 

clarified and the regulations be revised. 

Response:

 Under the revised guidance, the agencies continue to assert jurisdiction over 

wetlands that are adjacent to traditional navigable waters as that term is defined in the 

agencies regulations.. The agencies disagree with commenters and conclude that at least 

five justices agreed that such wetlands are “waters of the United States.” The agencies 

agree that the guidance should provide some further clarification of the term “adjacent” 
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and have revised the guidance to identify, consistent with the regulations and agency 

practice, the three criteria the agencies use to determine whether a wetland is adjacent.