1. Wetland Types, Functions, and DCM’s GIS Wetland Data
North Carolina Department of Environment and Natural Resources
Division of Coastal Management
January 2002

2. DCM GIS Wetland Data: Wetland Type Data
Wetland Functional Significance Data
Potential Wetland Restoration and Enhancement Site Data
Wetland Restoration Site Functional Significance Data (in progress)
January 2002

3. Topics Wetlands Wetland Functions Wetland Types GIS Wetland Data
NC-CREWS Data
Getting DCM’s Data
January 2002

4. Wetlands
Wetlands are areas that are periodically or permanently inundated by surface or ground water and support vegetation adapted for life in saturated soil. Wetlands include swamps, marshes, bogs and similar areas.
January 2002

5. What do wetlands do? Wetland Functions
Habitat nesting, spawning, rearing and resting sites for aquatic and land species, food chain production
Hydrology protection of other areas from wave action and erosion, storage areas for storm water and flood water, ground and surface water aquifer recharge
Water water quality protection, water filtration and Quality purification, treatment of nonpoint source runoff
January 2002

6. Why are wetlands important?
Wetland Values
maintain biodiversity
provide habitat for animals
maintain water quality
support commercial fishing, forestry
reduce flood damage
hiking, fishing, hunting,
bird watching, boating
aesthetic value
Did you know?
Nationwide, an estimated 50 million people spend approximately $10 billion annually observing and photographing wetland-dependent birds.
January 2002

7. There are many different kinds of wetlands.
People place different values on them based on the functions they perform.
January 2002

8. Where are wetlands located?
Wetlands are located throughout NC
There are two kinds of maps in NC that show the locations and types of wetlands:
National Wetland Inventory (NWI) Maps
DCM Wetland Type Maps
January 2002

9. Example of National Wetland Inventory (NWI) Map
NWI maps show many different wetland types
January 2002

10. P F O 4 What?
The U.S. Fish & Wildlife Service’s National Wetland Inventory (NWI) uses what is called the Cowardin Classification to classify wetlands. This classification system is used by scientists and resource managers nationwide. This complex system can be difficult for the average user to interpret.
January 2002

11. DCM’s wetland maps are easy to understand because wetlands are grouped into well-known categories.
January 2002

12. Example: DCM Wetland Type Map
DCM’s maps show 13 wetland types
Example: DCM Wetland Type Map
January 2002

13. DCM’s GIS Wetland Type Data
Show the location, type, and amount of wetlands in the North Carolina Coastal Plain
January 2002

14. DCM’s GIS Wetland Type Data uses these primary GIS layers
National Wetland Inventory (NWI) Maps
NRCS Digital Soils Maps
Satellite Imagery , 1994
Hydrography
January 2002

15. January 2002

16. DCM Wetland Classification
DCM Wetland Types:
Swamp Forest
Bottomland Hardwood
Pocosin
Pine Flat
Hardwood Flat
Managed Pine
Freshwater Marsh
Salt/Brackish Marsh
Estuarine Scrub Shrub
Estuarine Forest
Maritime Forest
Headwater Swamp
Human Impacted
Modifiers:
Partially Drained/ Ditched
Cut-over
Cleared
January 2002

17. DCM Wetland Classification
Hydrogeomorphic Classification (HGM):
This classification describes the hydrology and the geomorphic setting of a wetland
Riverine
Flat or non-riverine
Tidal
January 2002

18. The following slides show photos of wetland types typically found in Coastal North Carolina.
January 2002

19. Riverine Swamp Forest
January 2002

20. Headwater Swamp
January 2002

21. Swamp Forest
January 2002

22. Pocosin Wetland
January 2002

23. Wet Pine Flat
Hard Wood Flat
January 2002

24. Tidal Salt Marsh
January 2002

25. Are DCM’s GIS Wetland Maps Accurate?
January 2002

26. Accuracy Assessment
Over 600 field sites visited
Accuracy was calculated to be 89% for wetlands and 71% for uplands.
That means most of the sites we map as wetlands are indeed wetlands. Most of the sites we map as uplands are non-wetlands.
January 2002

27. Maps are the starting point
DCM’s wetland maps show the location and types of wetlands
What is the ecological significance
of these wetlands?
How important are they?
January 2002

28. A model that rates the functional significance of wetlands
North Carolina Coastal Region Evaluation of Wetland Significance (NC-CREWS)
A model that rates the functional significance of wetlands
January 2002

29. NC-CREWS Ratings
DCM staff developed a model that produces ratings for each wetland polygon in our GIS:
Beneficial Functional Significance
Substantial Functional Significance
Exceptional Functional Significance
Wetlands can be evaluated on the basis of an overall rating or in terms of individual functions.
January 2002

30. NC-CREWS Primary Wetland Functions and Subfunctions
Water Quality
Nonpoint Source Removal
Floodwater Cleansing
Wildlife Habitat
Terrestrial Wildlife
Aquatic Life
Hydrology
Surface Runoff Storage
Floodwater Storage
Shoreline Stabilization
Potential Risk
Wetland Extent and Rarity
Replacement Difficulty
Land Use Characteristics
January 2002

31. Example: Water Quality Function
January 2002

32. Example: DCM GIS Wetland Type Map
DCM wetland maps show wetland location and type.
January 2002

33. Example: NC-CREWS Map
NC-CREWS rates a wetland’s ecological functional significance
January 2002

34. January 2002

35. The following slides show an example of our online data.
Web-Based Viewing at
Click on Wetlands
Click on Wetlands Data
Scroll down and click on Go to the Wetlands Data
This application will allow you to view DCM’s wetland data online. You can begin by clicking or selecting a county or town. The wetland data will draw when you have zoomed in far enough. The map also includes major roads and water for reference.
The following slides show an example of our online data.
January 2002

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39. How to get DCM GIS Wetland Data:
From DCM on a CD as Arc/Info Export or Shapefile
Wetland type, NC-CREWS, Restoration/Enhancement type data
From CGIA- Wetland type and Restoration/Enhancement type data
Transfer via FTP site
Wetland Type data is in CGIA’s BasinPro
January 2002