You are not logged in. Login

July 1, 2011 - ASCE Comments - Regarding Identification of Waters Protected by the Clean Water Act

Click here for PDF of document 

EPA and Army Corps of Engineers Guidance
Regarding Identification of Waters Protected by the Clean Water Act
Notice of availability and request for comments
Docket ID No. EPA-HQ-OW-2011-0409
76 Fed. Reg. 24479 (May 2, 2011)

July 1, 2011

∗ ASCE was founded in 1852 and is the country's oldest national civil engineering organization. It represents 140,000 civil engineers individually in private practice, government, industry, and academia who are dedicated to the advancement of the science and profession of civil engineering. ASCE is a non-profit educational and professional society organized under Part 1.501(c) (3) of the Internal Revenue Code.

The Environmental Protection Agency
The Defense Department
EPA and Army Corps of Engineers Guidance
Regarding Identification of Waters Protected by the Clean Water Act
Docket ID No. EPA-HQ-OW-2011-0409


On May 2, 2011, the Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (USACE) issued a notice of availability and request for comments. The notice concerned a proposed guidance that describes how the agencies will identify waters protected by the Clean Water Act and implement the Supreme Court’s decisions in Solid Waste Agency of Northern Cook County v. U.S. Army Corps of Engineers, 531 U.S. 159 (2001), and Rapanos v. U.S., 547 U.S. 715 (2006). The agencies believe the proposed guidance will increase the number of waters able to be protected by the Clean Water Act compared to current practice and that this improvement will aid in protecting the nation’s public health and water resources. The guidance will steer federal policy until the agencies adopt a regulation establishing the limits of federal jurisdiction under the Clean Water Act. 76 Fed. Reg. 24479.1

The American Society of Civil Engineers (ASCE) believes that the draft guidance is a reasonable attempt at finding a workable, short-term solution to the question of federal command over waters of the United States. It emphasizes the science of water in the decisionmaking process while attempting to balance conflicting statutory requirements. The fundamental issue, however, is one of the application of law, and no agency guidance or rulemaking—no matter how scientifically sound—can resolve satisfactorily the crucial constitutional and legal problems over the scope of federal control of U.S. waters. Congress ultimately needs to enact legislation to determine definitively the limits of the Clean Water Act caused by the ambiguous language in the current Act over what constitutes “waters of the United States.”


Congress enacted the Federal Water Pollution Control Act Amendments of 1972 (the Clean Water Act) "to restore and maintain the chemical, physical, and biological integrity of the[n]ation's waters.” One of the mechanisms adopted by Congress in 1972 to achieve that purpose was to borrow language from the Rivers and Harbors Act of 1899 to prohibit under section 404 the discharge of any pollutants into "navigable waters" without a permit issued by the United States or an authorized state. The CWA then stated that "[t]he term 'navigable waters' means the waters of the United States, including the territorial seas.”

In 1935, the Supreme Court established mean high water as the lateral extent of navigable waters jurisdiction under the Rivers and Harbors Act. “Regulating up to the mean high tide line was sufficiently extensive for purposes of navigation, because very little navigation takes place in the shallow, frequently dry area shoreward of the mean high tide line.” William L. Want, L. of Wetlands Reg. § 2:8 (2011).

Congress clearly wanted to expand the jurisdiction of the federal government to “navigable” waters above the mean high tide in order to protect wetlands, which by 1972 were recognized as increasingly important ecological and economic resources.2

The final statute only confused the issue. Lawmakers adopted language from the Rivers and Harbors Act, a 19th century statute, to define those waters that were subject to regulation as "navigable waters," which under the 1899 Act had been interpreted to extend only to mean high water. The ambiguity was created by the addition of statutory language defining "navigable waters" as "waters of the United States," a term Congress chose not to define in the CWA. Id.

In any case, section 404 of the Clean Water Act of 1972 limits the addition of pollutants and other materials into the waters of the United States. Section 404 limits the destruction of the environment from industrial activity through a system of discharge permits issued by the U.S. Army Corps of Engineers.3 Not every discharge into waters of the U.S. requires a permit, however.

In 1974, the Corps issued a rule that restricted the scope of section 404 to waters of the United States that are actually capable of carrying commercial traffic from one state to another. The rule sought to limit the scope of the 404 regulatory program only to those navigable waters regulated under section 10 of the Rivers and Harbors Act of 1899. The 1974 rule was invalidated by the U.S. District Court for the District of Columbia, which held that the Clean Water Act jurisdiction extended to waters that do not meet “the traditional tests of navigability.”

The Corps of Engineers then enacted regulations to enlarge the permit program's coverage in three stages. The first phase began immediately upon publication of the regulation in 1975 and included all waters subject to the ebb and flow of the tide or waters that were or are susceptible to use for commercial navigation purposes (waters already being regulated by the Corps), plus all adjacent wetlands to these waters. In the second phase (effective on September 1, 1976) the Corps included primary tributaries to the Phase I waters and lakes greater than five acres in surface area, plus wetlands adjacent to these waters. Phase III became effective on July 1, 1977, and included all waters of the United States. See id. All waters above the headwaters of non-tidal rivers and other waters remained beyond federal reach and have always been open to development without a Corps permit.4 


In 1985, the Supreme Court first attempted to define federal jurisdiction under the CWA in United States v. Riverside Bayview Homes, when it held that the Corps had broad power to regulate wetlands adjacent to navigable bodies of water and their tributaries under section 404. These wetlands, the Court concluded, could reasonably be regulated if the Corps found that they were “inseparably bound up” with “waters of the United States” that were subject to the Clean Water Act. The Court also discarded a prerequisite that the regulated lands be under water.

In January 2001, however, the opinion in Solid Waste Agency of Northern Cook County (SWANCC) v. United States Army Corps of Engineers retreated from the broad ruling in Riverside Bayview Homes and restricted federal jurisdiction over intrastate waters for the first time. To come within federal protection, the SWANCC Court said, the wetlands need to exhibit a “significant nexus” to navigable waters, a conclusion, the majority argued, that was in fact based on a principle in Riverside Bayview Homes. The decision eliminated federal jurisdiction over isolated wetlands that were (or could be) used by migratory birds. The SWANCC Court indicated that the states could fill the gap left by the shortened federal leash over intrastate waters. 

The opinion seemed to indicate that all waters within a single state eventually could be beyond the reach of the Clean Water Act absent a clear connection to interstate commerce. Although SWANCC was limited only to certain isolated waters, its practical effect was to leave remote wetlands at risk of destruction from industrial activities due to the uncertainty in the minds of federal and state regulators over the reach of the Act. “[T]he Supreme Court's (SWANCC) ruling has practically eliminated federal regulation of isolated wetlands.” Want, L. of Wetlands Reg. § 4:31. Moreover, the decision was seen at the time by many as a major revision to the Act. “In ruling that the Corps and the [Environmental Protection Agency] no longer had jurisdiction over isolated intrastate waters, the Court fundamentally changed section 404 wetlands regulatory programs.” SWANCC Supreme Court Decision: Impact on Wetlands Regulations: Hearing Before the Subcomm. on Fisheries, Wildlife, and Water of the Senate Comm. on Envt. and Pub. Works, 108th Cong. 1 (2003) (statement of Sen. Crapo).

In 2006, a badly divided Court further reduced federal controls on development activities in wetlands located wholly within one state. Five justices rejected the scope of the 1977 regulation over all waters of the United States. But only four justices questioned the Corps regulation of intrastate wetlands and concluded in Rapanos v. United States that the Act protects only “relatively permanent, standing [,] or flowing bodies of water.” Justice Scalia reasoned that only those wetlands with a continuous surface connection to “waters of the United States” are themselves subject to Clean Water Act jurisdiction. The plurality stated that wetlands “with only an intermittent, physically remote hydrologic connection to 'waters of the United States' do not implicate the boundary-drawing problem of Riverside Bayview, and thus lack the necessary connection to covered waters that we described as a 'significant nexus' in SWANCC .”

Justice Kennedy argued that federal jurisdiction extends to those waters where “a significant nexus” to interstate waters based on the Act's goals and purposes of restoring and maintaining maintain the chemical, physical, and biological integrity of the nation's waters. Rejecting the proposition that federal jurisdiction requires a direct hydrologic connection, he argued that “the Corps' conclusive standard for jurisdiction rests upon a reasonable inference of ecologic interconnection, and the assertion of jurisdiction for those wetlands is sustainable under the Act by showing adjacency alone.”5

All nine justices agreed, however, that the term “waters of the United States” includes some waters that are not navigable in the traditional sense. But the plurality concluded that “SWANCC rejected the notion that the ecological considerations upon which the Corps relied in Riverside Bayview . . . provided an independent basis for including entities like ‘wetlands’ (or ‘ephemeral streams’) within the phrase ‘waters of the United States.’” Therefore “[t]he concepts of ‘tributary,’ ‘adjacency,’ and ‘significant nexus’ are the main jurisdictional issues in the post-SWANCC debate.” Tracie-Lynn Nadeau and Mark Cable Rains, Hydrological Connectivity between Headwater Streams and Downstream Waters: How Science Can Inform Policy, 43 J. AM. WATER RES. ASS’N, 119 (2007).

In 2009, EPA told Congress that, under the rulings in SWANCC and Rapanos, at a minimum, approximately 59 percent of the nation's stream miles and 20 percent of its remaining wetlands are at risk of losing protections. Thousands of miles of streams and millions of acres of wetlands could be subject to uncontrolled industrial pollution and damage. s. rep. no. 111-361, 4-5, 2010 WL 5137046, 4 (footnote omitted). Nevertheless, “the extent of CWA jurisdiction over such non-navigable tributaries (and adjacent wetlands) remains uncertain.” Ronald M. Soiefer et al., Federal and state environmental regulatory laws—Clean Water Act, 4 Successful Partnering between Inside and Outside Counsel § 72:30 (2011). 


The Draft Guidance will identify waters that (1) are clearly subject to CWA jurisdiction as traditionally navigable waters; (2) interstate waters; (3) or waters that may be covered by the CWA under the “significant nexus” test, as determined on a case-by-case basis, including tributaries, adjacent wetlands, and physically proximate waters. Finally, the guidance will attempt to identify waters that are generally not subject to CWA jurisdiction. Draft Guidance at 4.

“The agencies expect . . . that under the understandings stated in this draft guidance, the extent of waters over which the agencies assert jurisdiction under the CWA will increase compared to the extent of waters over which jurisdiction has been asserted under [Bush administration] guidance, though certainly not to the full extent that it was typically asserted prior to the Supreme Court decisions in SWANCC and Rapanos.” Id. at 3.

The agencies contend that determining a “significant nexus” will be one of the document’s most important tasks. When assessing whether a “significant nexus” exists, “field staff should look for indicators of hydrology, effects on water quality, and physical, chemical, and biological (including ecological) connections or functions . . . alone or in combination with similarly situated waters, [and] more than speculative or insubstantial effect on the chemical, physical, or biological integrity of downstream traditional navigable waters or interstate waters.” Id. at 8. 



ASCE agrees that the agencies must seek jurisdiction over waters with a significant nexus to traditional navigable waters or interstate waters. The Guidance states that a “significant nexus” will occur whenever the waters, alone or with similar waters in the region, will have a significant adverse impact on the chemical, physical or biological integrity of traditional navigable waters or interstate waters when contaminated. Id. at 7.

Some have argued that the presumed harm to distant waters from polluted wetlands or headwaters must be fairly predictable for federal jurisdiction to apply. “Under the CWA, it must be foreseeable that a discharge into a remote water or wetland will detrimentally affect water quality in the downstream traditionally navigable water.” Lawrence R. Liebesman et al., Rapanos v. United States: Searching for a Significant Nexus Using Proximate Causation and Foreseeability Principles, 40 ENVTL. L. REP. NEWS & ANALYSIS 11242, 11246 (2010).

But this is an approach from tort law, not science. Although the science of water does not readily yield a precise measure of damage or timing caused by a pollutant flow in a legally definable manner, it seems utterly foreseeable that harm of the sort that alters the physical, chemical or biological integrity of the receiving waters is more than likely to occur.

For elements that have no gaseous form (e.g., the limiting nutrient phosphorous, most trace metals), the only possible fate once introduced to streams is transport to downstream floodplains, reservoirs or coastal zones, although this transport may require anywhere from days to centuries.

Martin W. Doyle and Emily S. Bernhardt, What is a stream? 45 ENVTL. SCI. & TECH. 354, 356 (2011) (emphasis added).6

This is precisely the fate that satisfies the Kennedy opinion’s demand for a “significant nexus.” Hydrologic pathways—precipitation, surface runoff, groundwater, tides and river floods—are the scientific determinant of federal jurisdiction under the Kennedy test. These pathways move energy and nutrients to and from wetlands. Indeed, hydrology is the single most important factor in determining the establishment and maintenance of wetlands and wetlands processes. WILLIAM J. MITSCH AND JAMES G. GOSSELINK, WETLANDS 107-108 (4th ed. 2007). The movement of water is responsible for the movement of toxic substances into wetlands, which may further influence the physical and chemical environment. Id. at 108. Likewise, groundwater hydrology is critical to the understanding of surface water flows. “Parts of the aquifer maintain connection with surface streams and are responsible for [the quality and quantity of the water in] base flows, while in other reaches the intermittent stream pattern indicates absence of connection, with the streambed acting as an infiltration site.” Guilherme Marques et al., Hydrodynamic Characterization of a Karst Aquifer in the Brazilian Semi-Arid Region with Time Series Analysis of Hydrology Data, in 9th Symposium of Groundwater Hydrology, Quality and Management, ASCE WORLD ENVIRONMENTAL AND WATER RESOURCES CONGRESS (2011) (emphasis added).

The plurality’s assertion in Rapanos that wetlands that are not directly or immediately connected on the surface to a regulated body of water are beyond the scope of the Act is scientifically unsound. It fails to recognize the physical behavior of water in the environment. The plurality’s total reliance on a surface connection entirely ignores the critical role of groundwater and local hydrological conditions in the functioning of healthy wetlands.

In sum, the plurality’s insistence in Rapanos that a surface connection is the only way to establish a significant nexus cannot be squared with the science of hydrology and wetlands classification, which is based on multiple hydrological factors, only one of which entails surface connectivity. The plurality in Rapanos ignored the inherently interstate nature of all watersheds and most wetlands.

An important tool in determining the “significant nexus” for federal regulation is a recently developed analytical tool designed to help understand the hydrology of wetland function. It is the hydrogeomorphic (HGM) approach. As mentioned above, wetland hydrology, including sources of water and hydrodynamics, is typically considered the single most important factor controlling wetland ecosystem processes.

The HGM approach is based on classification—or “hydrological segregation”— that results in an organization of wetlands according to different potential functions and benefits. The U.S. Geological Survey (USGS) frequently uses a modified HGM approach to categorize wetlands. The USGS assigns categories based on the wetlands’ position in the landscape, their soils and surficial geologic setting, and their sources of water. Traditionally, the USGS uses the HGM approach in a wetlands permitting setting, by comparing a particular wetland to a set of defined reference wetlands that span a functional integrity spectrum, to determine the degree to which the wetland in question functions as a degraded or an undegraded example of wetlands with similar hydrology.

In addition, groundwater-flow patterns and water quality in a variety of hydrogeologic settings in various wetlands are strongly affected by landscape features. These landscape features may be strongly related to bedrock or surficial lithology, geologic structure, mineral composition of the aquifer material, or a combination of any or all of them. In other words, the soil, rock, and water beneath a wetland are as important—if not more so—to a well-functioning aquatic system. To repeat, water below the surface is a key element in the flow of rivers and streams.

Groundwater underlies the earth's surface everywhere, and in most places, especially in humid climates, it is in direct contact with surface-water bodies. Groundwater is in constant motion through flow systems of various magnitudes, and these flow systems commonly interact with surface-water bodies. As a result,
groundwater flow systems can be thought of as subsurface tributaries of streams.

Thomas C. Winter, The Role of Ground Water in Generating Streamflow in Headwater Areas and in Maintaining Base Flow, 43 J. AM. WATER RES. ASS’N 23 (2007) (emphasis added).

Hydrological factors are important to the understanding of the nature and performance of wetlands. None of them is properly understood in the SWANCC or Rapanos decisions. Without a technically sound, systematic understanding of how water behaves, the Supreme Court could not provide a scientifically based rationale for its decisions.

The guidance properly considers jurisdictional waters on a watershed basis. Watershed geomorphology (the dimensions of basins and watersheds) has been recognized as important to the understanding of the hydrology of watersheds for more than half a century. See Arthur N. Strahler, Quantitative Analysis of Watershed Geomorphology, 38 TRANSACTIONS AM. GEO. UNION 913 (1957) (defining landform properties of watersheds and stream orders).


The EPA guidance cannot fill the statutory and regulatory gaps left by the Supreme Court opinions.

As the draft correctly notes at the outset, the guidance is not a law or regulation and is therefore not legally binding. Draft Guidance at 1. If finalized, it will merely serve as a manual to direct EPA and USACE staff in the processing of 404 permits under those much-reduced agency rules left intact by the two Supreme Court opinions and already mandated in the Clean Water Act.

Congress must amend the Act to clarify federal jurisdiction over wetlands, establish clearly where states must assume responsibility, and provide appropriate federal oversight. Such legislation ought to:

• Maintain federal jurisdiction over all interstate and navigable waters, their tributaries, and all adjacentwetlands under the pre-2001 U. S. Army Corps of Engineers’ regulatory program under the Commerce Clause in the U.S. Constitution using an unambiguous test for significant nexus to navigable-in-fact waters.

• Clarify state jurisdiction under section 404 of the Clean Water Act over isolated, non-navigable intrastate waters and their adjacent wetlands, including vernal pools, playas, and prairie potholes, considering recent Supreme Court decisions and other jurisdiction based on environmental and wildlife considerations under

regulations promulgated by the Department of the Interior or the Environmental Protection Agency.

• Amend the Clean Water Act to clarify purely environmental federal jurisdiction over intermittent and ephemeral streams and their adjacent wetlands under section 404 of the U.S. Army Corps of Engineers, in coordination with the Environmental Protection Agency.

It is especially important that legislation provide inducements to the states to make greater efforts to protect their remaining wetlands, particularly isolated wetlands, which make up the bulk of all upland wetlands. NatureServe, Biodiversity Values of Geographically Isolated Wetlands in the United States 9, (accessed June 8, 2011).

Isolated wetlands are found in every state and make up a significant portion of all U.S. wetlands. The most commonly occurring isolated wetlands are those that are separated geographically. Ralph W. Tiner, Geographically Isolated Wetlands in the United States, 23 WETLANDS 494 (2003). In the past, federal
officials have identified isolated wetlands as deserving special attention due to their ecological and economic values. “While all wetlands are important in ecological functioning on a watershed scale, some are better protected than others; isolated wetlands and waters are particularly at risk . . . .” EPA, FY02 Wetland
Program Development Grants Guidelines, 66 Fed. Reg. 46,450, 46,452 (2001). “Small isolated wetlands can be of great cumulative importance to the aquatic ecosystem.” USACE, Clean Water Act Regulatory Programs, 58 Fed. Reg. 45,008, 45,024 (1993).

There are practical needs for legislation as well. With more of the burden for protecting wetlands falling on the states, Congress must amend the Act to provide incentives for the states to strengthen their programs to protect all wetlands through federal standards established under the Clean Water Act. A major goal should be to increase delegation of the section 404 program—with stringent federal standards and oversight—to authorized states to implement the federal program beyond the two states currently authorized to issue permits in lieu of the Corps of Engineers. One incentive could be realized by authorizing the use of grant
money under section 106 for state wetland protection programs that meet minimum federal standards.

Congress needs to ensure that isolated wetlands receive full federal protections. With these in place, the states need to increase their efforts to preserve vital wetlands, including isolated water bodies, within their borders under section 404. Only Michigan and New Jersey now operate federally delegated wetlands programs. The remaining states need assistance to become full partners with the federal government in preserving wetlands, including geographically isolated wetlands.

Moreover, the Supreme Court opinions in SWANCC and Rapanos, in interpreting the Act’s congressional statement of policy, appeared to assume that the states would take on the major responsibility for protecting isolated wetlands under principles of federalism. This simply has not happened. 7 The proposed EPA guidance cannot resolve the issue of the widespread lack of state implementation of regulation of isolated wetlands under state law.

Respectfully submitted,