Water And Oceanography

Preserving Wetlands a Natural Security Issue



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Wetlands ecosystems and habitats are protected as "Waters of The United States" under The Clean Water Act just the same as lakes, rivers, and ocean shores. Wetlands serve as important resources, not only to the plants and creatures which inhabit them, but to humans as well. For in addition to their aesthetic, ecologic, and recreational functions to our communities, they also serve as flood water retention basins and pollution filters for our cities. Wetlands have been shown to absorb toxins and pollutants (actually metabolizing them in many cases!) where open water ecosystems have been shown to be more severely and adversely affected by similar quantities of the same contaminants.

Wetlands habitats are transitional between aquatic and terrestrial ecosystems and may possess some of the characteristics of either or both. Section 404 of the Clean Water Act declares wetlands to be considered as "the Waters of the United States" and as such affords them the same protection provided to lakes, rivers, and other aquatic ecosystems. Wetlands include marshes, swamps, bogs, stream banks, beaches, and floodplains.

According to the Clean Water Act (33 USC 1344), Corps of Engineers Wetlands Delineation Manual (1987), The Federal Manual for Identifying and Delineating Jurisdictional Wetlands (1989, currently under moratorium), and other Federal publications, wetlands are defined as "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."

The protection of wetlands has been instituted because of the numerous ecological and human values that they afford. These values include, but are not necessarily limited to, fish and wildlife habitat, retention of floodwaters, erosion control, recreational activities, groundwater aquifer recharge, aesthetics, and pollution control by assimilating, chemically degrading, and biologically metabolizing pollutants and toxins released by humans into the natural environment. Wetlands rival tropical rain forests in their ability to remove carbon dioxide from and liberate oxygen into the atmosphere by shear virtue of their productivity and biomass. Hence, numerous State and Federal regulations have been instituted to protect these valuable wetlands resources.

Identification of wetlands is based upon three general criteria... vegetation, soils, and hydrology. Hydrophytic (water-loving) vegetation includes those species that are uniquely adapted to withstand saturated soil conditions. The National List of Plant Species That Occur in Wetlands (Reed, 1988) lists all of the plant species known to occur in wetlands and gives their indicator status, which is a measure of the probability of finding them in wetland or upland habitats.

The U.S.D.A. Soil Conservation Service's Hydric Soils of The United States (1987) defines hydric soils as those soils that are saturated or inundated for sufficient frequency and duration (at least a week or more during the growing season) to develop anaerobic conditions (little or no oxygen) in the surface soil layer. Evidence of anaerobic conditions includes gleying (shift from reddish to grayish colors due to lack of oxygen), mottling (blotchy bright and dark color patterns due to intermittent saturation), and the accumulation of dark organic material humus, muck, peat) which is retained in the soil due to the lack of aerobic (oxygenated) soil conditions.

Hydrology is the ultimate driving force that gives rise to wetland conditions. Generally, the wetlands hydrology criterion has been met when permanent or periodic saturation or inundation occurs at or near the ground surface for a week or more during the growing season. Evidence of wetlands hydrology includes visual observations of saturation or inundation, oxidized root zones of plants, water-marks, drift or debris lines, sediment deposition, scoured soil surfaces, water-stained leaf litter, drainage patterns, special plant adaptations, evidence of hydrophytic vegetation ecosystem ecology, and hydric soils.

Wetlands are identified and their boundaries are delineated on the basis of the three criteria discussed above. Generally, all three of these criteria must be met in order for an area to be identified as a wetland. The Corps of Engineers Wetlands Delineation Manual (1987) provides specific detailed methodologies to be used for making jurisdictional wetlands determinations and for preparing wetlands delineation reports.

Some activities that may take place in Jurisdictional Wetlands are allowed without prior notification to the Army Corps of Engineers. These activities fall under the Nationwide Permit Program which allows for the filling of up to one acre of isolated wetlands, carrying out certain construction and maintenance activities, minor road crossings, etc. (provided that other regulations such as those for stream alteration, headwaters, coastal waters, floodplains, and other State and Local Regulations are observed).

If Jurisdictional Wetlands are present, the Army Corps of Engineers recommends that a Wetlands Delineation Report (as defined by the Corps Manual) be prepared by a competent consultant and maintained by the developer/landowner in case of the event that site work is called into question or that a demonstration of "due diligence" is necessary.

It is NOT necessary to notify the Corps when:

1. The activity will not affect Jurisdictional Wetlands if present.

2. The activity falls under a Nationwide Permit except for those instances where Predischarge Notification (PDN) may be required.

3. The project site does not contain Jurisdictional Wetlands.

It IS necessary to notify the Corps when:

1. The activity is not covered by or exceeds coverage afforded by a Nationwide Permit or where PDN is required.

2. The activity falls under other Federal, State, or Local regulations for which permits may be required such as stream alteration, coastal waters, floodplains, headwaters protection, unique ecology, etc.

Observing these recommendations for Corps notification will relieve the Corps, the developer, and the local government of burdensome and unnecessary expense, paperwork, and project delays. Obtaining Letters of Jurisdiction or Non-Jurisdiction from the Corps per local Zoning and/or Planning Board request (especially when no wetlands are present, when the activity falls under a Nationwide permit, or when the activity will not affect a wetland) can take as long as six months, involves financial losses including the loss of potential tax revenues, costs for project delays, consultant fees, as well as the burden and expense of extra paperwork... none of which are even necessary or required by Federal Regulations.

When requesting individual permits for regulated activities above and beyond those afforded by the Nationwide Permit Program and in those instances where an activity is covered by a Nationwide permit but Predischarge Notification (PDN) is required anyway, wetlands reports are submitted to the U.S. Army Corps of Engineers along with any required permit applications for subsequent review and approval. When permits are requested for any regulated activities, joint approval is generally required from the State's Department of Environmental Conservation under the NEPA program.

In every instance where a project may affect The Waters of The United states or where Jurisdictional Wetlands are present a good environmental consultant or wetlands scientist advises and assists his or her clients in avoiding the disturbance of such areas by planning developments around these ecologically sensitive areas. When wetlands disturbance is unavoidable, the client is advised to minimize disturbance as much as possible under the conditions of the Nationwide Permit Program which has been designed to allow development activities where Jurisdictional Waters are present but with minimal environmental impacts to the Waters of the United States, including valuable wetlands ecosystems. This policy of avoidance over minimization over mitigation (only as a last resort) is also recommended by the Army Corps of Engineers.

The methodology currently employed in wetlands delineations follows that given in the U.S. Army Corps of Engineers Wetlands Delineation Manual (1987) and incorporates the Routine Onsite determination Method as outlined in Part IV-A&B of that document. This method employs nine preliminary data-gathering procedures that were conducted prior to visiting the site followed by twenty-two site-characterization procedures that were conducted in the field.

Baselines and transects were established and mapped in the field along which changes in plant community type were identified and noted. Sampling points were established along each transect to further characterize vegetation community ecology including distribution and abundance of dominant species. Soil samples were collected and hydrologic observations were made at each sampling point in each plant community or vegetation unit encountered.

The Transect/Sampling Point Map shows the vegetation units encountered during the present investigation. Vegetation and soil data as well as hydrologic observations were recorded on the data sheets (1987 Dataform-1) in Appendix A. Visual estimations of dominant plant species distribution and abundance were made and recorded. Dominant species were ranked according to the probability of finding them in wetland or upland habitats. Wetland indicator status rankings were obtained from the National List of Plant Species That Occur in Wetlands National Summary as well as regional and State lists (Reed, 1988; U.S. Government Printing Office).

The field portions of a wetlands investigation consist of traverses along the site boundaries as well as multiple transects across the study site with the specific goal of detecting and identifying any potential wetland habitats and/or upland vegetation units. Plant and soil samples were collected for subsequent laboratory examination and more precise identification. Visual estimates of the percent aerial extent of major plant species were made and recorded. Observations on both surficial and downhole hydrologic conditions were made and recorded. Dominant plant species in each stratum of each vegetation unit were determined according to the Methods described herein.

Soil samples were collected by means of a manually driven soil probe capable of extracting 1-inch cylindrical soil core samples. Samples were taken from the ground surface to depths of 12 to 24 inches below grade. Soil sampling was also conducted by shovel-test borehole construction. These samples were subjected to both field and laboratory analyses and were compared with the descriptions given in the USDA Soil Survey for the county in question. The samples collected were subjected to visual, olfactory, and colorimetric examination for indications of hydric conditions.

Standard Munsell Soil Color Charts are used for colorimetric determinations in an effort to detect signs of gleying, mottling, and other wetlands soil indicators. The Hydric Soils of the United States (USDA Soil Conservation Service, 1987) was consulted for determining hydric soils as well as for identifying those soils with the potential for having hydric inclusions. Hydrologic observations were made on the boreholes and test pits from which soil samples were collected. Previously-published State and Federal wetlands maps were also reviewed for the presence of any wetlands detected during earlier studies in the vicinity. The Transect/Sampling Point Map shows the locations where soil samples were collected. Munsell colors for the collected samples are given on the data sheets.

In addition to hydrologic field observations, topographic and geologic maps were consulted in order to ascertain influent, effluent, stationary, and subsurface hydrologic conditions affecting the study area. Additional soil sampling took place in any vegetation unit where the hydrophytic vegetation criterion was met to further refine delineated wetland boundaries. Soil sampling was also conducted in all other vegetation units for comparative purposes.

Vegetation Units (distinct biological communities) were identified on the basis of dominant plant species. (Example: Beech/Maple Upland Forest or Cattail/Bulrush Marsh.) Sharp vegetational changes and topographically defined boundaries were identified first. This was followed by careful examination and/or transect sampling of transitional or gradational vegetation unit boundaries. Outlines showing the vegetation unit boundaries for the entire site (wetland and upland) were drawn on a site map.

Visual estimates are made of the percent aerial extent of each major species in each stratum of each vegetation unit. The four vegetation strata described are: Tree, Sapling/Shrub, Vine, and Herb. All dominant species and their wetlands indicator status rankings were recorded on data sheets for each stratum and then again for all strata at each sampling point within each vegetation unit.

The Hydrophytic Vegetation Criterion. When 50% of all dominant species from all strata in a vegetation unit were OBL, FACW, or FAC, the hydrophytic vegetation requirement was considered to have been met. If 50% of all of the dominant plant species did not fall within the OBL/FACW/FAC group, the vegetation unit was not considered a wetland because the hydrophytic vegetation criterion was not met. (Caution was exercised to determine whether or not vegetation units lacking hydrophytic vegetation were "Special Case" wetlands or "Atypical Situations" as outlined in the Manual.)

If all dominant plant species in a vegetation unit were OBL and/or FACW with an abrupt boundary, hydric soils were assumed to be present... such units are wetlands. If any dominant species was ranked FAC or lower, soils were examined in greater detail for hydric characteristics. If the hydrophytic vegetation criterion is not met and none of the "Special Case" situations described in the Manual apply, the vegetation unit is not a jurisdictional wetland and no further action may be necessary. (It should be noted, however, that State and Federal regulations make provisions for special cases where one or more criteria may be lacking but particular ecological, historic, scientific, cultural, or social value may necessitate conservation and preservation measures.)

The Hydric Soils Criterion. In order to determine whether or not the hydric soils criterion was met, previously-published information such as the Soil Survey and Hydric Soils of the United States were consulted. Additionally, field sampling was conducted and soils were examined for hydric indicators such as gleying, mottling, iron concretions, unoxidized organic materials, etc. Vegetation units meeting the hydric soils and the hydrophytic vegetation criteria were delineated as wetlands. In vegetation units where these criteria were lacking, upland status was assigned. However, caution was exercised to determine whether "Special Case" wetland status was applicable.

The Hydrology Criterion. The presence of wetlands hydrology was determined by looking for evidence of saturation, inundation, or evidence of shallow depth to the water table for a week or more during the growing season (April through October). Field indicators included: water marks, plant adaptations, channels, "piping", black-stained leaves, standing water, hydrogen sulfide odor (rotten egg smell), debris lines, etc. Although certain hydrologic indicators are very subtle, it should be noted that hydrology is the ultimate driving force in wetland development. Vegetation units exhibiting overwhelming evidence of wetlands hydrology were delineated as wetlands. Units, where one or two of the three wetlands criteria were lacking, were examined carefully for "Special Case" conditions. Vegetation units not meeting any or all of the three wetlands criteria were assigned upland status.

Wetland boundaries as determined by the methods described above were flagged, surveyed, and mapped. These methods culminated in the preparation of the wetlands delineation map given below.

Hydric soils form in areas where water accumulates for any significant amount of time during the year. Standing water has the tendency to seal out oxygen such that only plant species uniquely adapted to survive in anoxic (low oxygen) soil environments can flourish. Low oxygen environments are acidic/reducing (as opposed to basic/oxidizing) and tend to favor the accumulation of organic materials (humus, muck, peat) and the leaching (dissolution and migration) of nutrients such as iron, manganese, and calcium carbonate (limestone) from the soil. These nutrients percolate downward very slowly and precipitate (crystallize out of solution) in soil layers where the acidity is lower. This explains the presence of iron/manganese nodules and the absence of calcium carbonate that were encountered in some of the wetland soils during the Site Wetlands Investigations.

When water fills the pore spaces between soil particles and covers the soil surface, the rate that oxygen diffuses through the soil is drastically reduced. Diffusion of oxygen through water-logged soils (wetlands) has been shown to be 10,000 times slower than oxygen diffusion through porous media such as well drained soils. Oxygen depletion in saturated soils takes place within several hours to several days after inundation begins, depending on the oxygen demands of the organisms and chemical compounds in the soil.

The resulting lack of oxygen prevents plants from carrying out normal aerobic (oxygenated) root respiration and also affects the availability and abundance of both nutrients and metabolic toxins in the soil. Thus, ferric iron (+3) which normally imparts a reddish-brown color to oxidized soils, becomes reduced (gives up oxygen). The reduced sediments, dominated by ferrous iron (+2) sulfide (FeS) are often bluish gray to black in color (gleyed) and emit the odor of rotten eggs (hydrogen sulfide) when disturbed. In addition to the other hydric soil indicators and parameters discussed in the Methodology Section above, gleying and sulfurous odors were used as field indicators to aid in distinguishing between wetland and upland soils during the Site Wetlands Investigation.

Wetlands which are lower than their surroundings, as is usually the case, are subjected to surface water inflows of several types. Overland flow is a non-channelized sheet flow that usually occurs during and immediately following a rainfall or spring thaw. This type of flow is classically exemplified over much of the site where surface waters flow down gradient and from the site into streams which exit the site boundary.

Once established, wetland vegetation influences hydrologic conditions by binding sediments to reduce erosion, by trapping sediment, by interrupting water flows, and by building up peat deposits. Hence, even artificially-induced wetland conditions can become enhanced and perpetuated. Such artificially created wetlands habitats have been encountered in tire ruts and along utility easements and pipelines at the site. The disturbance caused by these pipelines has reduced drainage at the site and is responsible for actually enhancing wetland conditions and areas.

The preservation of wetlands will favor the drainage of developed portions of the site. All wetlands are protected by Section 404 of The Clean Water Act and are considered to be "Waters of The United States" no matter how they are formed.

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