[Code of Federal Regulations]

[Title 40, Volume 24]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR230.41]



[Page 268-269]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 230_SECTION 404(b)(1) GUIDELINES FOR SPECIFICATION OF DISPOSAL SITES 

FOR DREDGED OR FILL MATERIAL--Table of Contents

 

          Subpart E_Potential Impacts on Special Aquatic Sites

 

Sec.  230.41  Wetlands.



    (a)(1) Wetlands consist of areas that are inundated or saturated by 

surface



[[Page 269]]



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.

    (2) Where wetlands are adjacent to open water, they generally 

constitute the transition to upland. The margin between wetland and open 

water can best be established by specialists familiar with the local 

environment, particularly where emergent vegetation merges with 

submerged vegetation over a broad area in such places as the lateral 

margins of open water, headwaters, rainwater catch basins, and 

groundwater seeps. The landward margin of wetlands also can best be 

identified by specialists familiar with the local environment when 

vegetation from the two regions merges over a broad area.

    (3) Wetland vegetation consists of plants that require saturated 

soils to survive (obligate wetland plants) as well as plants, including 

certain trees, that gain a competitive advantage over others because 

they can tolerate prolonged wet soil conditions and their competitors 

cannot. In addition to plant populations and communities, wetlands are 

delimited by hydrological and physical characteristics of the 

environment. These characteristics should be considered when information 

about them is needed to supplement information available about 

vegetation, or where wetland vegetation has been removed or is dormant.

    (b) Possible loss of values: The discharge of dredged or fill 

material in wetlands is likely to damage or destroy habitat and 

adversely affect the biological productivity of wetlands ecosystems by 

smothering, by dewatering, by permanently flooding, or by altering 

substrate elevation or periodicity of water movement. The addition of 

dredged or fill material may destroy wetland vegetation or result in 

advancement of succession to dry land species. It may reduce or 

eliminate nutrient exchange by a reduction of the system's productivity, 

or by altering current patterns and velocities. Disruption or 

elimination of the wetland system can degrade water quality by 

obstructing circulation patterns that flush large expanses of wetland 

systems, by interfering with the filtration function of wetlands, or by 

changing the aquifer recharge capability of a wetland. Discharges can 

also change the wetland habitat value for fish and wildlife as discussed 

in subpart D. When disruptions in flow and circulation patterns occur, 

apparently minor loss of wetland acreage may result in major losses 

through secondary impacts. Discharging fill material in wetlands as part 

of municipal, industrial or recreational development may modify the 

capacity of wetlands to retain and store floodwaters and to serve as a 

buffer zone shielding upland areas from wave actions, storm damage and 

erosion.