Limits between wetland and deepwater systems also were distinguished, as they had been in the Circular 39 definition. Although the boundary between wetland and deepwater systems is important for inventory purposes, it is rarely at issue in regulatory disputes, and is not referred to at all in the regulatory definitions of wetland.

The 1979 report is significant for several reasons. First, it introduced the concepts of hydrophytes and hydric soils, and it was the impetus for the development of official lists of these (Chapter 5). Second, it embraced the concept of predominance (hydrophytes or undrained hydric soils had to be "predominant" in wetlands). Third, it introduced the use of three factors for wetland identification: soils, vegetation, and hydrology. Finally, it included some areas that lack vascular plants or soils. Each of these concepts was later developed in one or more of the wetland delineation manuals.

The hydrologic portion of the FWS definition is invoked only when the substrate is nonsoil, in which case the wetland must be "flooded or saturated at some time during the growing season of each year." This is the first appearance in a wetland definition of the concept of inundation or saturation during the growing season. Duration of flooding or saturation is not specified, although the classification system contains "water regime modifiers" that describe the duration of flooding in general terms.

Ten years after USACE began to regulate wetlands intensively, the Supreme Court, in United States v. Riverside Bayview Homes, 474 U.S. 121, 138 (1985), held that USACE had jurisdiction over discharges into wetlands adjacent to navigable waters, but it expressly left open the question of jurisdiction over wetlands that were not adjacent.

The Court looked at the legislative history of FWPCA and concluded that Congress's broad concern for protection of water quality and aquatic ecosystems made it reasonable for USACE to interpret the term "waters" to encompass wetlands adjacent to navigable waters. The Court also looked at the language in Section 404(g) concerning "adjacent wetlands" and construed the language to indicate that Congress intended "waters'' to include "adjacent wetlands.'' However, the Court stated that "section 404(g)(1) does not conclusively determine the construction to be placed on the use of the term 'waters' elsewhere in the Act (particularly in section 502(7)), which contains the relevant definition of 'navigable waters'."

FRONT MATTER (R1-R20)

EXECUTIVE SUMMARY (1-12)

1 INTRODUCTION AND BACKGROUND (13-19)

2 ECOLOGY OF WETLAND ECOSYSTEMS (20-42)

3 WETLAND DEFINITIONS: HISTORY AND SCIENTIFIC BASIS (43-64)

4 WETLAND DELINEATION: PAST AND CURRENT PRACTICE (65-89)

5 WETLAND CHARACTERIZATION: WATER, SUBSTRATE, AND BIOTA (90-148)

6 ESPECIALLY CONTROVERSIAL WETLANDS (149-167)

7 REGIONALIZATION (168-189)

8 MAPS, IMAGES, AND MODELING IN THE ASSESSMENT OF WETLANDS (190-206)

9 REGULATION OF WETLANDS: ADMINISTRATIVE ISSUES (207-214)

10 FUNCTIONAL ASSESSMENT OF WETLANDS (215-226)

REFERENCES (227-252)

APPENDIXES (253-296)

INDEX (297-306)

LIST OF PUBLICATIONS (307-308)