Wetlands & Other Waters of the United States
U.S. Army Corps of Engineers and the U.S. Environmental Protection Agency define wetlands as follows:
Wetlands are those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, and bogs. For an official determination of whether or not an area is classified as a wetland, contact the Army Corps of Engineers. (Source: 33 CFR 328)
Other waters include the following:
Navigable waters of the United States are those waters that are subject to the ebb and flow of the tide and or are presently used, or have been used in the past, or may be susceptible for use to transport interstate or foreign commerce. A determination of navigability, once made, applies laterally over the entire surface of the waterbody, and is not extinguished by later actions or events which impede or destroy navigable capacity. Precise definitions of navigable waters of the United States or navigability are ultimately dependent on judicial interpretation and cannot be made conclusively by administrative agencies. (Source: 33 CFR 329)
Waters of the United States include the following: (Source: 33 CFR 328 and Supplementary Information)
- All waters which are currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide.
- All interstate waters including interstate wetlands.
- All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce including any such waters:
- which are or could be used by interstate or foreign travelers for recreational or other purposes; or
- from which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or
- which are used or could be used for industrial purpose by industries in interstate commerce.
- All impoundments of waters otherwise defined as waters of the United States under the definition.
- Tributaries of waters identified in paragraphs 1-4 above.
- The territorial seas.
- Wetlands adjacent to waters (other than wetlands) identified in paragraphs 1-6 above.
- EPA has clarified that waters of the United States also include the following waters:
- which are or would be used as habitat by birds protected by Migratory Bird Treaties; or
- which are or would be used as habitat by other migratory birds which cross state lines; or
- which are or would be used as habitat for endangered species; or
- used to irrigate crops sold in interstate commerce.
Waste treatment systems, including treatment ponds or lagoons designed to meet the requirements of the CWA (other than cooling ponds as defined in 40 CFR 123.11(m) which also meet the criteria of this definition) are not waters of the United States. It should be noted that we generally do not consider the following waters to be Waters of the United States. However, the Corps and EPA reserve the right on a case-by-case basis to determine that a particular waterbody within these categories of waters is a water of the United States.
- Non-tidal drainage and irrigation ditches excavated on dry land.
- Artificially irrigated areas which would revert to upland if the irrigation ceased.
- Artificial lakes created by excavating and or diking dry land to collect and retain water and which are used exclusively for such purposes as stock watering, irrigation, settling basins, or rice growing.
- Artificial reflecting or swimming pools or other small ornamental bodies of water created by excavating and or diking dry land to retain water for primarily aesthetic reasons.
- Water filled depressions created in dry land incidental to construction activity and pits excavated in dry land for the purpose of obtaining fill, sand, or gravel unless and until the construction or excavation operation is abandoned and the resulting body of water meets the definition of waters of the United States.
Tidal waters means those waters that rise and fall in a predictable and measurable rhythm or cycle due to the gravitational pulls of the moon and sun. Tidal waters end where the rise and fall of the water surface can no longer be practically measured in a predictable rhythm due to masking by hydrologic, wind, or other effects. (Source: 33 CFR 328)
Ordinary high water mark (Source: 33 CFR 328 and 33 CFR 329) means that line on the shore established by the fluctuations of water and indicated by physical characteristics such as:
- a clear, natural line impressed on the bank;
- shelving;
- changes in the character of soil;
- destruction of terrestrial vegetation;
- the presence of litter and debris; or
- other appropriate means that consider the characteristics of the surrounding areas.
Ocean waters means those waters of the open seas lying seaward of the base line from which the territorial sea is measured, as provided for in the Convention on the Territorial Sea and the Contiguous Zone. (Source: 33 CFR 324)
Information, Links and Definitions
Technical Report Y-87-1 — Wetland Delineation Manual
Technical Report Y-87-1 is an annotated version of the Corps of Engineers official 1987 Wetland Delineation Manual. This on-line version is annotated to provide updated interpretations and changes. It also contains important links to other related information such as hydric soils data and listings of wetland plants and is available in PDF format.
Recognizing Wetlands
Non-technical information about the criteria used to identify wetlands. This non-technical brochure should not be used to delineate wetlands or to draw broad conclusions about the presence or absence of wetlands on a particular piece of property. For technical information about wetlands delineation, see the Wetland Delineation Manual. Actual delineation of wetlands should be done by trained and experienced persons.
Young Scientist
The Young Scientist's Introduction to Wetlands - put together by the Corps of Engineers just for students and children to help them learn about wetlands values and functions.
WES Wetlands Publications
Waterways Experiment Station publications about a variety of wetlands issues. WES is a major Corps of Engineers research facility and the author of the Wetland Delineation Manual. Contains a number of excellent technical reports & studies.
Wetlands and Agriculture
There are important relationships between Section 404 of the Clean Water Act and the "Swampbuster"
provisions of the Food Security Act, as administered by the Department of Agriculture. These are discussed in this document.
Courtesy List of South Carolina Environmental Consultants
List of private consultants available to perform evaluations of property in South Carolina for the presence of wetlands in PDF format. Please read carefully the information printed on this list. We do not "recommend" any consultants and anyone who tells you that they are "approved" by this office is misrepresenting the facts. This is a list of people and firms who have indicated that they are available to do this kind of work and the list is provided by this office as a public service. The work done by the consultant must be reviewed and verified in writing by the Corps of Engineers before it has any official meaning.
Technical & Biological Resources
A listing of resources provided by Corps Headquarters. Includes links to sites with information on wetlands
delineation, classification, functions and values, mitigation banking, restoration and management, and numerous other topics.
Questions concerning the Regulatory Program?
Call the "Project Manager of the Day" in the Charleston District Office(1) 866.329.8187 (Toll Free)
843.329.8044 (Local)
843.329.2332 (Fax)
Email point of contact for Charleston's Regulatory Division
Mailing Address:
US Army Corps of Engineers
Regulatory Division
69A Hagood Ave.
Charleston, South Carolina 29403-5107