The wetland features were delineated on the hardcopy orthophoto plots by trained biologists. Because the source materials were of relatively large scale, the minimum mapping unit for this data set is 0.25 acres, as opposed to 2.0 acres in the original WWI. The classification codes from the original WWI were followed with slight modification. For example, a line feature to identify drainage ditches (code "DD") too narrow to be depicted as polygons (generally narrower than 100 feet on the ground) was added. A point feature to show the location of drained wetlands (code "DW") was also added to show small areas that have been effectively drained for agriculture.
Wetlands and ponds less than 0.25 acres in size were located as point features. As in the original WWI, wetland polygons that contain at least 30 percent cover of a second wetland cover type were given a mixed label of two classification codes.
Wetland features were delineated after reviewing any available SEWRPC environmental project files for a given area. Field-verified wetland boundaries were directly copied (or plotted if in digital format) onto the orthophoto plots. Reference materials, such as digital files of hydric soil units and hardcopy USDA Food Security Act (FSA) wetland maps, were consulted to identify and confirm wetland features. Delineations were made using previous wetland boundaries from SEWRPC 2000 land use and 1985 vegetation inventories as a guide. Hardcopy prints of stereo aerial photography from 2005 were also used to locate and confirm wetland areas. In some cases the SEWRPC staff made field checks to verify wetland locations and boundaries.
The wetland delineations were then board digitized by SEWRPC staff. The features were collected into ESRI geodatabase format files and the digital map files were reviewed for accuracy and completeness. Hardcopy plots of the wetland features on a background of 2005 orthophotography were generated at 1"=400' scale for review by Commission staff. Corrections were annotated on the plots and the digital files were revised as necessary. A second set of hardcopy plots was generated from the revised files for delivery to the Wisconsin Department of Natural Resources (WDNR). The geodatabase files were translated to ESRI shapefile format, and the shapefiles were converted to the Wisconsin Transverse Mercator (WTM 83/91) coordinate system for delivery to the WDNR. After review of the hardcopy and digital products by the WDNR, SEWRPC staff made any necessary corrections to the geodatabase files and final versions of the shapefiles were delivered to the WDNR.
1) Wetland_Point -- consists of locations for wetland point symbols. The five major attributes collected for these features and their descriptions are as follows: [1] "PLS" (five-digit code that identifies the USPLSS survey township and its range direction); [2] "COUNTYID" (two-digit county code); [3] "CNTYNAME" (full county name); [4] "SYMBOL" (code for wetland point symbol; domain values are: 'WETLAND' = wetland smaller than one-fourth acre, '$WETLAND' = filled wetland smaller than one-fourth acre; 'POND' = pond smaller than one-fourth acre, 'DW' = drained wetland, and 'UPLAND' = upland surrounded by wetland); and [5] "DIGITIZED" (date of digitization in month and year). The majority of these attributes are similar to the attributes in the Wisconsin Wetland Inventory; the values for "SYMBOL" have been modified slightly and two features have been added to this field.
2) Wetland_Line -- contains line features depicting drainage ditches (identified by a major attribute field named "CODE" with domain value of 'DD'). These drainage ditch features are not part of the Wisconsin Wetland Inventory and are used as reference for Southeastern Wisconsin Regional Planning Commission projects and planning activities.
3) Dam_Line -- contains line features depicting the outline of earthen or other types of dams that create ponds or wetlands. These features are identified by a major attribute field named "CODE" with a domain value of 'DAM'.
4) Wetland_Poly -- this feature class contains polygons delineating the boundaries of wetlands and some upland areas. The ten major attributes collected for these features and their descriptions are as follows: [1] "PLS" (five-digit code that identifies the USPLSS survey township and its range direction); [2] "COUNTYID" (two-digit county code); [3] "CNTYNAME" (full county name); [4] "ORIGCODE" (original wetland classification); [5] "DIGITIZED" (date of digitization in month and year); [6] "WETCODE" (the current wetland classification, generally the same as "ORIGCODE"); [7] "CLASS" (generalized description of wetland classification); [8] "MINUNIT" (minimum mapping unit of two acres or less); [9] "PHOTODATE" ('2005' for this inventory); and [10] "MAPTYPE" (uppercase letter 'O' indicating orthophoto base). These attributes are a subset of the attributes in the Wisconsin Wetland Inventory.
The "WETCODE" and "ORIGCODE" polygon attributes are 10-character fields that uniquely identify each wetland polygon by type. The Wisconsin Wetland Inventory Classification Guide describes the vegetation class, subclass, and general hydrologic characteristics of the wetland area. A single classification code generally contains up to four alphanumeric characters (e.g. 'T3K'). If a second class of vegetation covers 30 percent or more of the polygon, then codes for both types of vegetation, separated by a slash ("/"), are placed in the attribute field (e.g. 'S3/E2Kg'). The dollar sign ("$") placed as a prefix before a code indicates a filled wetland (e.g '$T3K').
Each geodatabase file is organized to cover one U.S. Public Land Survey System survey township, for a total of 82 files in the data set. The file naming convention is "WI05_ttrr.mdb", where "WI05" indicates the 2005 wetland inventory, "ttrr" indicates the USPLSS township and range covered by the file, and ".mdb" indicates an ESRI geodatabase file. The files were compiled with reference to one-inch-equals-100-feet scale and one-inch-equals-200-feet scale orthophotography, and with reference to similar scale digital topographic mapping.
The township geodatabase files have also been merged into larger files covering each of the seven counties in the Southeastern Wisconsin Region. The county geodatabase files have been simplified such that the point feature class retains only the "SYMBOL" major attribute field, and the polygon feature class retains only the "WETCODE" and "CLASS" major attribute fields.
See the section of the document named "Digital Wisconsin Wetland Inventory Layer Description".
Detailed information about the Wisconsin Wetland Inventory can be found in the publication entitled "Wisconsin Wetland Inventory Classification Guide" (PUBL-WZ-WZ023, February 1992) available on the WDNR website at the following location: <http://dnr.wi.gov/wetlands/documents/WWI_Classification.pdf>
Additional information about the Wisconsin Wetland Inventory, including publications and acreage reports, can be found on the WDNR website at the following location: <http://dnr.wi.gov/wetlands/inventory.html>
Class | |
|
Hydrologic Modifier | |
|
E |
1 |
K |
a |
|
| Subclass |
|
| Special Modifier |
CLASS and SUBCLASS
A - Aquatic Bed 1 Submergent 2 Floating 3 Rooted floating 4 Free floating
M - Moss
E - Emergent / Wet Meadow 1 Persistent 2 Narrow-leaved persistent 3 Broad-leaved persistent 4 Nonpersistent 5 Narrow-leaved nonpersistent 6 Broad-leaved nonpersistent
S - Scrub / Shrub 1 Deciduous 2 Needle-leaved deciduous 3 Broad-leaved deciduous 4 Evergreen 5 Needle-leaved evergreen 6 Broad-leaved evergreen 7 Dead 5 Needle-leaved 6 Broad-leaved
T - Forested 1 Deciduous 2 Needle-leaved deciduous 3 Broad-leaved deciduous 5 Needle-leaved evergreen 7 Dead 8 Needle-leaved
F - Flats / Unvegetated Wet Soil 0 Subclass unknown 1 Cobble / gravel 2 Sand 3 Mud 4 Organic 5 Vegetated pioneer
W - Open Water 0 Subclass unknown 1 Cobble / gravel 2 Sand 3 Mud 4 Organic 5 Vegetated pioneer
U - Upland
|
HYDROLOGIC MODIFIER
L Standing water, Lake R Flowing water, River H Standing water, Palustrine K Wet soil, Palustrine
SPECIAL MODIFIER
a Abandoned cropland c Manmade cranberry bog e Exposed flats complex f Farmed in dry years g Grazed j Central Sands complex m Floating vegetated mats r Red clay complex s Ridge and swale complex v Vegetation recently removed w Floodplain complex x Excavated z Evidence of muskrat activity
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