Wetland Delineation

Updated 10/15/2008

The National Wetland Team provides guidance, tools, training, and leadership within NRCS regarding the development and application of science-based methods and tools related to wetland identification and delineation. Team members serve on several national and regional teams, including the National Technical Committee for Hydrophytic Vegetation, National Advisory Team to regionalize the 1987 Corps of Engineers Wetland Delineation Manual, and national and regional plant panels to update the 1988 National List of Vascular Plant Species That Occur in Wetlands. Additionally, the Wetland Team is leading an effort by NRCS to develop and deliver Wetland Delineation for NRCS, a training course which will be available to NRCS staffs through the National Employee Development Center. Team members hold lead roles and provide technical oversight in all existing NRCS training courses related to wetland identification and delineation, including hydric soils, advanced hydric soils, identification of hydrophytic vegetation, and hydrology tools for wetland delineation.

Policy

• NRCS - National Food Security Act Manual, http://www.nrcs.usda.gov/programs/compliance/pdf_files/3rdED-NFSAM_SEC513_v2006.pdf
• Highly Erodible Land and Wetland Conservation Rule http://www.nrcs.usda.gov/programs/farmbill/1996/HELRule.html
• Guidance on Conducting Wetland Determinations for the Food Security Act of 1985 and Section 404 of the Clean Water Act – Memorandum to the Field, 1995 http://www.nrcs.usda.gov/programs/compliance/pdf_files/COE_NRCS_wetland.pdf
• Memorandum of Agreement Among the COE, EPA, USF&WS and the NRCS for the Purpose of Transferring Responsibilities for Updating and Maintaining the National List of Vascular Plant Species that Occur in Wetlands. http://www.usace.army.mil/cw/cecwo/reg/mou/moa_vascularplant.pdf
• Developing a Regionalized Method Version of the Corp of Engineers Wetland Delineation Manual: Issues and Recommendations http://www.usace.army.mil/cw/cecwo/reg/Developing%20a%20Regionalized%20Version%20of%20the%20Corps%20Wetlands%20Deli.pdf
• NB.180.8.8, CPA – Vegetation Indicator Status Designation Modifiers for Certified Wetland Determinations; http://directives.sc.egov.usda.gov/viewerFS.aspx?id=4106
• Use of the COE Regional Supplements in conducting wetland delineations (May 10, 2007) http://directives.sc.egov.usda.gov/viewerFS.aspx?id=3319

Methods

• 1987 Corps of Engineers Wetland Delineation Manual http://el.erdc.usace.army.mil/elpubs/pdf/wlman87.pdf
• Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Alaska Supplement http://www.usace.army.mil/cw/cecwo/reg/erdc-el-tr-06-3-web.pdf
• Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Arid West Supplement http://www.usace.army.mil/cw/cecwo/reg/inte_aridwest_sup.pdf
• Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Great Plains Supplement, draft for peer review testing. http://www.usace.army.mil/cw/cecwo/reg/greatplains_supp_peer_review_draft_9-10-2006.pdf

Tools

Soils

• Field Indicators for Hydric Soils in the United States ftp://ftp-fc.sc.egov.usda.gov/NSSC/Hydric_Soils/FieldIndicators_v6_0.pdf
• Using Soil Taxonomy to Identify Hydric Soils (PDF 9 MB)
• Redoximophic Features (PowerPoint 4.6 MB)
• Field Indicators of Hydric Soil (PowerPoint 6.7 MB)
• Overview of Hydric Soils (PowerPoint 132 KB)

Vegetation

• 1988 National List of Vascular Plant Species that Occur in Wetlands http://www.fws.gov/nwi/Plants/list88.html
• 1993 Northwest region 9 Supplement to the 1988 National List http://www.fws.gov/nwi/Plants/list88.html
• 1996 National List of Vascular Plant Species that Occur in Wetlands http://www.fws.gov/nwi/Plants/list96.html. Note: This list has NOT been approved for use by NRCS.
• NRCS Midwestern Wetland Flora; a field office guide to plant species http://www.npwrc.usgs.gov/resource/plants/floramw/index.htm
• NRCS Western Wetland Flora; a field office guide to plant species http://www.npwrc.usgs.gov/resource/plants/florawe/index.htm
• NRCS Southern Wetland Flora; a field office guide to plant species http://www.npwrc.usgs.gov/resource/plants/floraso/index.htm
• NRCS Northeastern Wetland Flora; a field office guide to plant species http://www.npwrc.usgs.gov/resource/plants/florane/index.htm
• Online Plant Identification Keys http://npdc.usda.gov/technical/plantid_wetland_mono.html

Hydrology

• Scope & Effect Equations http://www.wli.nrcs.usda.gov/technical/web_tool/tools_java.html
• Chapter 19, NRCS Engineering Field Manual, “Hydrology tools for Wetland Determination.” http://www.info.usda.gov/CED/ftp/CED/EFH-Ch19.pdf

Other Related Information

• Technical Note No. 190-73 : Identification of Plant Species’ Trinomials with Varying Wetland Indicator Status Designations: Northeast Region n

• Field Indicators of Hydric Soils in the United States  
  Introduction to Hydric Soil Terminology (163 KB) PowerPoint
  Introduction to Hydric Soil Terminology (40 KB) PDF

• National List of Plant Species that Occur in Wetlands
• Midwestern Wetland Flora Guide
• Western Wetland Flora Guide
• Southern Wetland Flora Guide
• Northeast Wetland Flora Guide
• Woody Plant and Plant Family Keys
• Scope and Effect Equations
• Wetland Delineation Technical Series, Number 2: Rainfall Documentation for Field Investigations and Aerial Photography Interpretation