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Wambach, C. J. 2005. What is, isn’t wetland. PE Consultants LLC www.peconsultants.net/whatiswetland.htm
Definition: COE 1987 & WDOE 1997
Duration of Inundated or Saturated or Soil
Incorrect Regulatory Reviews And Politics
Summary of the U.S.COE and WDOE Wetland Delineation Manuals
This article was written to provide some clarification on “what is and what is not a wetland” in response to a recent news article in the Olympian newspaper. Often, wetland issues get wrapped up in the politics of land use and the “not in my back yard syndrome.” Neighbors, political figures, and regulatory agents (which sometimes are one in the same) have contributed to an article in the Olympian designed to charge public emotion regarding a project on a Thurston County property. The brunt of the article is directed at our wetland study on this property. Although PE Consultants LLC was mentioned as a centerpiece of the article, no representative of our company was asked for an interview. Our study followed the strictest guidelines of the 1987 U.S. Army Corps of Engineers and the 1997 Washington Department of Ecology (DOE) manuals for identifying and delineating wetlands. Our in-depth, 4 month study of site hydrology, soils, and vegetation assisted in our wetland determination on this difficult/disturbed site.
The contributing opponents of our study are basing their position on an hour or so of field investigation to our 4 months of rigorous field work. I was present during their field investigation. When I asked questions on their reasoning, the County reviewer had gotten angry and hostile. No explanation was given. The County reviewer had asked the DOE to assist in their wetland review. The DOE reviewer, along with the county reviewer, was on the site for about an hour. Both of the reviewers did not agree on “what is, isn’t wetlands” on the site. This disagreement further added to the confusion among the regulatory agents. The DOE reviewer contradicted the County reviewer’s desire to call most of the site wetlands. Nonetheless, the results of this minimal field review fueled the opposing political forces against this minimal impact project. And hence, the one-sided article in the Olympian with only the opinion of the opposing reviewers, excluding any input of the company that actually performed the study. Below, is a summary of the COE (Environmental Laboratory, 1987) and DOE (DOE, 1997) wetland identification and delineation manuals describing “what is, isn’t a wetland.”
Definition: COE 1987 & WDOE 1997
Wetlands. 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, bogs, and similar areas.
The official definition of wetlands may need some clarification of key precepts that may determine what is a wetland and what is not a wetland. These questionable precepts are listed below:
In addition, the Shoreline Management Act and Growth Management Act definitions add: “Wetlands do not include those artificial wetlands intentionally created from nonwetland sites, including, but not limited to, irrigation and drainage ditches, grass-lined swales, canals, detention facilities, wastewater treatment facilities, farm ponds, and landscape amenities, or those wetlands created after July 1, 1990, that were unintentionally created as a result of the construction of a road, street, or highway. Wetlands may include those artificial wetlands intentionally created from nonwetland areas to mitigate the conversion of wetlands.”
Explicit in the definition is the consideration of three environmental parameters: hydrology, soil, and vegetation. Positive wetland indicators of all three parameters must be present in wetlands. Although vegetation is often the most readily observed parameter, sole reliance on vegetation or either of the other parameters as the determinant of wetlands can be misleading. Many plant species can grow successfully in both wetlands and nonwetlands, and hydrophytic vegetation and hydric soils may persist for decades following alteration of hydrology that will render an area a nonwetland. The presence of hydric soils and wetland hydrology indicators in addition to vegetation indicators will provide a logical, easily defensible, and technical basis for the presence of wetlands. The combined use of indicators for all three parameters will enhance the technical accuracy, consistency, and credibility of wetland determinations. Therefore, all three parameters were used in developing the criteria for wetlands and all approaches for applying the criteria embody the multiparameter concept.
In wetlands soil saturation usually constitutes the upper 12 inches of the soil profile. For soil saturation to impact vegetation, it must occur within a major portion of the root zone of the prevalent vegetation. The major portion of the root zone is that portion of the soil profile in which more than 50 percent of the plant roots occur. In wetlands, this usually constitutes the upper 12 inches of the soil profile.
For indicators of saturation to the surface in the hydrology criterion, observations are made within a major portion of the root zone (usually within 12 inches), again in the 16-inch or deeper test pit. Visual observation of standing water within 12 inches of the surface may, under certain circumstances, be considered a positive indicator of wetland hydrology (i.e., saturation to the surface). When using water table within 12 inches of the surface as an indicator of hydrology, care must be used to consider conditions and the soil types (i.e., to ensure that the capillary ability of the soil texture is considered in regard to the water table depth).
Ground-water well data should be supplemented with observations of the soil profile and the capillary fringe. This can be done by examining a soil profile in the nearby vicinity of a ground-water well when the ground water is measured. Observations of surface ponding and/or flooding should also be made. In addition, soil temperatures at approximately 20 inches should be recorded to adequately determine extent of the growing season at that site if the growing season is in question.
The 1997 DOE Wetland Identification and Delineation Manual recommends that the sample adequately reflect seasonal hydrology and its effect on vegetation. Generally, in western Washington, groundwater monitoring wells should be monitored for a period during the rainy season between about mid-October to mid-June to capture both dormancy and new growth with consideration taken of the growing season.
Duration of Inundated or Saturated or Soil
Generally speaking, areas which are seasonally inundated and/or saturated to the surface for more than 12.5 percent of the growing season are wetlands. Areas saturated to the surface between 5 percent and 12.5 percent of the growing season are sometimes wetlands and sometimes uplands. Areas saturated to the surface for less than 5 percent of the growing season are non-wetlands. The percent of growing season translates to a number of days, depending on the length of the growing season in any particular area (e.g., 12.5% of a 170 day growing season is 21 consecutive days).
The length of time an area is wet for hydrology is based on consecutive days during the growing season. If an area is only saturated to the surface for a period of between 5 percent and 12.5 percent of the growing season and no clear indicators of wetland hydrology exist (i.e., recorded or field data), then the vegetation test should be critically reviewed. Specifically, in such cases a vegetative community dominated by FAC species would generally indicate that the area is not a wetland (unless the FAC-neutral test was indicative of wetlands---see below). The actual number of days an area is inundated and/or saturated to the surface for an area to be called a wetland varies; the identification of an indicator of recorded or field data is necessary to document that an area meets the wetland hydrology criterion of the 1987 Manual. The number of days specified in the June 1991 Hydric Soils of the United States is usually more than 2 weeks during the growing season.
The 1987 COE Wetland Delineation Manual defines the growing season as:
“The portion of the year when soil temperatures at 19.7 inches below the sol surface are higher than biologic zero (5 degrees C). For ease of determination this period can be approximated by the number of frost-free days.”
For much of Western Washington the mesic growing season has, in the past, been considered a good rule of thumb; i.e., 1 March to 31 October (except for some coastal areas which may have a year round growing season and in areas that have more extreme winter temperatures which may result in a shorter growing season). However, this should not be used to conflict with field data and observations.
In Skipopa soils, for example, wetland hydrology occurs on the site if soils are saturated within 12 inches of the surface for about 22 consecutive days. From 9 to 22 days of soil saturation within the upper 12 inches, the site may or may not be a wetland depending on the soil profile and vegetation criteria.
The COE (Environmental Laboratory, 1987) and DOE (DOE, 1997) manuals definition of hydrophytic vegetation is “the sum total of macrophytic plant life growing in water or on a substrate that is at least periodically deficient in oxygen as a result of excessive water content [hydrophytes]. Hydrophytes are any macrophyte (vascular plant) that grows in water or on a substrate that is at least periodically deficient in oxygen as a result of excessive water content; plants typically found in wet habitats.
The COE (Environmental Laboratory, 1987) and DOE (DOE, 1997) manuals describe a wetland rating system for plants. Each plant species is assigned a probability of occurrence within wetlands, which is referred to as its wetland status. The wetland rating system is as follows:
In general, under the 1987 Federal methodology, more than 50 percent of the dominant plant species within a test plot must be rated FAC or wetter (i.e., FACW, OBL) to satisfy the wetland criteria for hydrophytic vegetation. Dominant species are those that have a percent cover greater or equal to 20 percent within the test plot. In high diversity communities, dominant plant species may comprise 20 or more plant species. In low diversity communities, dominants will be less than 5 or 3 and may only be 1 species. Sound professional judgment based on careful observation and data collection must be used in selecting dominant species.
A hydric soil is a soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part. Anaerobic conditions cause redoximorphic features to develop, which can be evidenced through the observation of mottling or gleying in the soil.
The definition and criteria for hydric soils may change periodically as a result of revisions by the National Technical Committee for Hydric Soils (NTCHS). The most recent NTCHS version should be used. A hydric soil may be either drained or undrained, and a drained hydric soil may not continue to support hydrophytic vegetation or wetland hydrology. Therefore, not all areas having hydric soils will qualify as wetlands. Only when a hydric soil supports hydrophytic vegetation and the area has indicators of wetland hydrology may the area be referred to as a wetland.
A drained hydric soil is one in which sufficient ground or surface water has been removed by artificial means such that the area will no longer support hydrophytic vegetation. Although it is important to record such evidence of drainage of an area, a hydric soil that has been drained or partially drained still allows the soil parameter to be met. However, the area will not qualify as a wetland if the degree of drainage has been sufficient to preclude the presence of either hydrophytic vegetation or a hydrologic regime that occurs in wetlands.
Although all soil-forming factors (climate, parent material, relief, organisms, and time) affect the characteristics of a hydric soil, the overriding influence is the hydrologic regime. The unique characteristics of hydric soils result from the influence of periodic or permanent inundation or soil saturation for sufficient duration to affect anaerobic conditions. Prolonged anaerobic soil conditions lead to a chemically reducing environment, thereby lowering the soil redox potential. This results in chemical reduction of some soil components (e.g. iron and manganese oxides), which leads to development of soil colors and other physical characteristics that usually are indicative of hydric soils.
Hydric soils may be classified into two broad categories: organic and mineral. Organic soils (Histosols) develop under conditions of nearly continuous saturation and/or inundation. All organic soils are hydric soils except Folists, which are freely drained soils occurring on dry slopes where excess litter accumulates over bedrock. Organic hydric soils are commonly known as peats and mucks. All other hydric soils are mineral soils. Mineral soils have a wide range of textures (sandy to clayey) and colors (red to gray). Mineral hydric soils are those periodically saturated for sufficient duration to produce chemical and physical soil properties associated with a reducing environment. They are usually gray and/or mottled immediately below the surface horizon, or they have thick, dark-colored surface layers overlying gray or mottled subsurface horizons.
Note: Many soils are a combination of mineral and organics.
Normal circumstances is an integral and important term in determining the extent of jurisdiction under the Clean Water Act. The term comes from the definition of wetlands: “Wetlands are those areas that are inundated and saturated for a frequency and duration sufficient to support and, under NORMAL CIRCUMSTANCES do support a prevalence of vegetation typically adapted to life in saturated soil conditions.
As used in the 1987 Federal definition of wetlands, under normal circumstances refers to situations in which the vegetation has not been substantially altered by human activities. "Normal circumstances" has been further defined as "the soil and hydrologic conditions that are normally present, without regard to whether the vegetation has been removed." The determination of whether normal circumstances exist in a disturbed area "involves an evaluation of the extent and relative permanence of the physical alteration of wetlands hydrology and hydrophytic vegetation" and consideration of the "purpose and cause of the physical alterations to hydrology and vegetation." However, the majority of wetlands in the western Washington lowlands have been altered by human activities, which confuses the definition of “normal circumstances’.
The 1997 DOE Wetland Delineation Manual describes that the original intent of this term was to assure that the extent of Federal jurisdiction would not be obscured by human-caused activities done without benefit of a Section 404 Permit. For example, if an individual removed the vegetation of a wetland, it would still be a wetland under normal circumstances. That is, physically removing the vegetation neither eliminates the site from jurisdiction nor from the definition of wetlands. The same would hold true if fill materials were placed in wetlands without benefit of permit; the area is still under the jurisdiction of the Federal Government even though the wetlands have been covered by unauthorized fill.
However, through 150 years of land alteration associated with agriculture, development, road construction, grading, filling, draining, water diversion, flood control, damming rivers, lowering lakes, mineral mining, logging, and other human alteration, the definition of “normal circumstances” seems less applicable. The majority of wetlands in western Washington have been altered by human activity, and thereby, do not contain the strictest definition of “normal circumstances.” Many wetlands that I have encountered in my almost ten years of wetland work have been altered by human activity in one form or another. The identification of wetlands in these areas may constitute special identification methodologies presented in the 1987 COE and the 1997 DOE manuals, namely the “Atypical” and “Problem Areas” Methodologies (see discussion below).
In some cases, hydric soils have been legally drained as a part of historical agricultural activities. Although it is important to record such evidence of drainage of an area, a hydric soil that has been drained or partially drained still allows the soil parameter to be met. However, the area will not qualify as a wetland if the degree of drainage has been sufficient to preclude the presence of either hydrophytic vegetation or a hydrologic regime that occurs in wetlands. NOTE: The mere presence of drainage structures in an area is not sufficient basis for concluding that a hydric soil has been drained; such areas may continue to have wetland hydrology. Groundwater monitoring wells evaluated through the growing season can assist in the determination of drained hydric soils. If the hydric soil no longer satisfies the hydrology criterion, the area is not considered a wetland.
In addition, the Shoreline Management Act and Growth Management Act definitions add: “Wetlands do not include those artificial wetlands intentionally created from nonwetland sites, including, but not limited to, irrigation and drainage ditches, grass-lined swales, canals, detention facilities, wastewater treatment facilities, farm ponds, and landscape amenities, or those wetlands created after July 1, 1990, that were unintentionally created as a result of the construction of a road, street, or highway. Wetlands may include those artificial wetlands intentionally created from nonwetland areas to mitigate the conversion of wetlands.”
In such cases that do not meet the definition of normal circumstances as a result of human alteration, an alternative method must be employed in making wetland determinations. These “atypical situations” occur when natural events or human actions alter a wetland so that one or more of the three parameters are difficult to determine. If the alteration is a natural event or a lawful, human action that has altered the hydrology of the site so that wetland conditions no longer exist, then the site should be identified as a nonwetland.
Natural events may also result in sufficient modification of an area such that indicators of one or more wetland parameters are absent. For example, changes in a river course may significantly alter hydrology, or beaver dams may create new wetland areas that lack hydric soil conditions. Catastrophic events (e.g. fires, avalanches, mudslides, and volcanic activities) may also alter or destroy wetland indicators on a site.
Such “atypical situations” occur throughout Washington, and all of these cannot be specifically identified in the wetland manuals.
A vast account of wetlands in western Washington have undergone extensive human alteration as a result of agricultural activities, development, road construction, grading, filling, draining, water diversion, flood control, damming rivers, lowering lakes, mineral mining, and logging. In many western Washington wetlands, “normal circumstances” does not apply. In some areas, the land has been altered so extensively that the original condition of the land prior to human alteration is not applicable to delineate existing wetland conditions. For example, wetlands on the fringes of Lake Washington are not delineated to the extent prior to lowering of the lake by 15 feet. If so, millions of dollars of existing prime real estate would be in violation of Section 404 of the clean water act. It is the intention of wetland regulations to define wetlands based on existing conditions taking into account legal human-caused land alteration.
Because of 150 years of land alteration, the definition of “normal circumstances” does not always apply. The majority of wetlands in western Washington has been altered by human activity, and thereby, do not contain the strictest definition of “normal circumstances.” Many wetlands have been altered by human activity in one form or another. Because of the long history of human alteration resulting in impacted soils, vegetation, and hydrology of wetlands, the ‘Routine On-site Determination Method’ typically used by wetland biologists to identify and delineate unimpacted wetlands is not always a valid methodology. The identification of wetlands in these areas may constitute special methodologies presented in the 1987 COE and the 1997 DOE manuals, namely the “Atypical” and “Problem Areas” Methodologies.
‘Problem Areas’ and ‘Atypical Situations’ methodologies are more appropriate in areas difficult to determine wetland conditions. These methodologies are published in the wetland identification and delineation manuals produced by both the COE and DOE. ‘Problem Areas’ and ‘Atypical Situations’ determination methodologies require more extensive evaluation of wetland indicators and require additional data collection. Atypical situation refers to areas in which one or more parameters (vegetation, soil, and/or hydrology) have been sufficiently altered by recent human activities or natural events to preclude the presence of wetland indicators of the parameter (Environmental Laboratory, 1987--Appendix A Glossary). Problem areas are wetland types in which wetland indicators of one or more parameters may be periodically lacking due to normal seasonal or annual variations in environmental conditions that result from causes other than human activities or catastrophic natural events.
Nonwetlands include uplands and lowland areas that are neither deepwater aquatic habitats, wetlands, nor other special aquatic sites. They are seldom or never inundated, or if frequently inundated, they have saturated soils for only brief periods during the growing season, and, if vegetated, they normally support a prevalence of vegetation typically adapted for life only in aerobic soil conditions.
Nonwetlands typically meet the following criteria (based on normal circumstances):
(1) Vegetation. The prevalent vegetation consists of plant species that are typically adapted for life only in aerobic soils. These mesophytic and/or xerophytic macrophytes cannot persist in predominantly anaerobic soil conditions.
(2) Soil. Soils, when present, are not classified as hydric, and possess characteristics associated with aerobic conditions.
(3) Hydrology. Although the soil may be inundated or saturated by surface water or ground water periodically during the growing season of the prevalent vegetation, the average annual duration of inundation or soil saturation does not preclude the occurrence of plant species typically adapted for life in aerobic soil conditions.
In some cases, hydric soils have been legally drained as a part of historical agricultural activities. Although it is important to record such evidence of drainage of an area, a hydric soil that has been drained or partially drained still allows the soil parameter to be met. However, the area will not qualify as a wetland if the degree of drainage has been sufficient to preclude the presence of either hydrophytic vegetation or a hydrologic regime that occurs in wetlands. NOTE: The mere presence of drainage structures in an area is not sufficient basis for concluding that a hydric soil has been drained; such areas may continue to have wetland hydrology. Groundwater monitoring wells evaluated through the growing season can assist in the determination of drained hydric soils. If the hydric soil no longer satisfies the hydrology criterion, the area is not considered a wetland.
In addition, the Shoreline Management Act and Growth Management Act definitions add: “Wetlands do not include those artificial wetlands intentionally created from nonwetland sites, including, but not limited to, irrigation and drainage ditches, grass-lined swales, canals, detention facilities, wastewater treatment facilities, farm ponds, and landscape amenities, or those wetlands created after July 1, 1990, that were unintentionally created as a result of the construction of a road, street, or highway. Wetlands may include those artificial wetlands intentionally created from nonwetland areas to mitigate the conversion of wetlands.”
Incorrect Regulatory Reviews
And Politics
A Case Study.
The official definition of wetlands was formulated as a result of federal regulation of wetlands following Section 404 of the Clean Water Act. State and local also regulate alterations to wetlands through State and local ordinances. Counties and Cities regulate wetlands through their wetland ordinances. However, since wetland science is not perfect and depends on the subjective interpretation of the field investigator, different conclusions can be generated by different investigators on the same potential wetland. Alternate conclusions can also be drawn from using different methodologies (see discussion above on “Atypical” and “Problem Areas” methodologies).
The wrong conclusion can be drawn by using the wrong methodology. Disturbed areas that are difficult to make a wetland determination because one or more parameters are missing or because recent disturbance has created an unusual admixture of upland and wetland indicators can cause some confusion and disagreement among wetland investigators. That is why it is important to use the correct methodology, document scientific data, and interpret that data correctly. Regulators usually do not have the time or resources to apply the “Atypical Methodology” in the field or to review the more in-depth data and reporting that this methodology generates. If a wetland investigator uses the “Routine Onsite Determination Method” in human-disturbed areas, the wrong conclusion may be drawn.
On one recent project, Agency regulators spent less than an hour in the field reviewing my 4-month evaluation of a property. One area was recently disturbed by logging, grubbing, and plowing to make pasture. Another area has a cut ditch running through it and has been continually managed for pasture for at least several decades. My study consisted of the installation of groundwater monitoring wells to evaluate the groundwater table, the evaluation of the affects of capillary fringe, the evaluation of the soil profile to 5 feet in depth, the documentation of existing plant species, and the documentation of disturbance features. This in-depth study congealed numerical data with observations of onsite wetland indicators to assist in wetland determinations on a disturbed, difficult site. Part of the evaluation was to determine the “normal circumstance” of the site, for which the wetland determination was based upon.
Disturbed Field is Not a Wetland
I found that the recently disturbed field is not a wetland because:
It was determined that the “normal circumstance” of this recently disturbed area was non-wetlands. Four months of soils, hydrology, and plant species information using the more involved “Atypical Method” has yielded unique information on this area. The “Routine Onsite Determination Method” (or the first glance technique) used by the regulatory investigators may not provide the depth of information required to make a wetland determination in this recently disturbed area. The evaluation of soil profiles to 5 feet below the surface has revealed that the soil unit consists of upland soils that have been disturbed through logging, grubbing, and disking (plowing). Soil structure is consistent with the upland Skipopa soil type, which also occurs on the adjacent property. Thereby, upland soils would be the site’s “normal circumstance.”
Remnant upland plants, including large Douglas fir, revealed the “normal circumstance” plant community. The “Routine Onsite Determination Method” (or the first glance method) would have confused the investigator with the enigma of wet disturbed soils and upland vegetation. If a wetland determination was made using this “first glance method”, it would have been based on conflicting information and would have been entirely unjustified and indefensible. Yet, regulatory reviewers are sometimes faced with such dilemmas, and end up defending determinations based on incorrect presumptions using an incorrect methodology. Thereby, it is somewhat easy to understand how some regulatory investigators could confuse a disturbed upland field with a wetland.
Ditched Pasture is Not a Wetland
The area containing the ditch was not a wetland because:
One investigator claimed that a large lake once existed some time in history in this small area, so this area should be a wetland, claiming that the lake was the “normal circumstance.” However, no evidence of a large lake in this small area was presented. Perhaps, it was rumor or just a hunch. There is no doubt that the County had altered this area by constructing a road and excavating a drainage channel through it, and that the property owner had managed this area as pasture for many years. Over decades of legal land use, this area had developed a new “normal circumstance.” One can say that the area had naturalized into an upland, exhibiting drained soils and mostly upland vegetation, even though wet-adapted plants and hydric soils may persist for decades following the alteration of hydrology (1987 COE manual & 1997 DOE manual p.6, Paragraph 17). In addition, the subject area does not qualify as a wetland because the degree of drainage has been sufficient to preclude the presence of either hydrophytic vegetation or a hydrologic regime that occurs in wetlands (1987 COE manual & 1997 DOE manual p.21, paragraph 36(d)).
Although wetland science is an imprecise science, if wetland investigators, including regulatory agents, closely adhere to the Federal and State wetland identified and delineation manuals, less confusion and a greater consensus may occur. The Federal manual provides a general guideline for identifying and delineating wetlands. Whereas the more recent State manual provides a local guidance to identifying and delineating wetlands within the State of Washington. These manuals provide different methodologies that must be adhered to in order for the wetland investigator to provide an accurate wetland determination. If the wrong methodology is used, the wetland determination may be incorrect.