Editing SHP file attribute table to export for ArcMap user?

[Anonymous]

Our local government, in all its wisdom, is asking environmental consultants to submit delineated wetland areas in SHP format. This is not so bad, but they insist on the SHP files having very specific attribute tables associated with them. They give instructions on how to do this in ArcMap, which is what they use. I am using AutoCAD Map, and my SHP files are not being accepted, and I don't know how to create the accompanying tables in order to satisfy them.

Excerpt of their email indicating what was wrong with my files:

"Are the shapefiles with named Wetland 1 and Wetland 2 the ones you want me to use for ABWRET-A evaluation? The shapefile named Layer0_0 has two wetlands together and has more information in the attributes which is required for ABWRET-A evaluation. I am a bit confused that the polygons in Layer0_0 and Wetland1/2 are different. Please confirm the wetland extent and re-send us the shapefiles (use the attached wetland boundary template). The wetland area should be in square meters. Also WET_Area = VEG_Area + OW_Area, and VEG_Area = MR_Area + SW_Area + BOG_Area + FEN_Area. Please have the coordinate system in NAD_83_10TM_AEP_Forest (that is the coordinate system used in the template). If possible, can you please have the information of the two wetlands in one ABWRET-A form and delineate the wetland in one set of shapefiles?"

Any help is very much appreciated! Thanks in advance.

Liesl

[ChicagoLooper]

You have neither geometry nor data in any of your shapefiles. Is your site in Canada? I ask because your .prj is CSRS (Canadian Spatial Reference System). I have worked on a number or projects which involve delineating wetlands in the south, Mississippi, Florida, Louisiana (but never in Canada) for permit review by USACE.

If you are trying to convert your shapefile from dwg,it's not hard. The easiest is to separate the wetlands and uplands by layers. If you use descriptive names for your layers it will be easy. For example, a layers named Wetland Boundary, River (or stream or creek), open water, etc. If you have five polygons representing five wetland boundaries, put them all on the same layer. You'll need to 'attached' object data to the polygons prior to exporting to shapefile in order to have attributes, for example  WL-1, WL-2, WL-3, etc. for the wetland IDs.

You should to attach your dwg or a 'test' drawing for explanation and demonstration purposes. It's not hard if you already have a GIS background.  

[Anonymous]

Thank you for the reply! I have remade the SHP file (for one of the wetland areas) and I created some object data for it. (This is what took me so long to figure out.)

Now that I have this step, I still don't seem to have those attributes showing any values. (Sorry if I am using the wrong terminology.)

Yes, I am in Canada and using  CANA83-10TM115-EAP projection for this project.

So now the question remains how to export this SHP with the OW_Area field populated. This should be the total area of the polygon. Oh and the SHAPE box should also say polygon. I don't know how to connect the data to these fields.

I have attached the new SHP files and a PDF of what it looks like. 

[parkr4st]

Mapexport the shp without the OW_Area field as a closed polyline

Mapimport the polyline, select AREA from properties and name the target OW_Field

the new shp will have the area in the OW_Area field

Dave

[Anonymous]

Thanks Dave, I am still having issues with this. Where during MAPIMPORT am I able to create AREA? I don't think I am doing the process correctly at all. Are there any good tutorials on creating SHP with custom object data tables? I have searched and found some that are OK, but nothing that shows exactly what I need. 

I have ArcGIS for AutoCAD loaded but I don't find that useful at all, but again I may not be using it properly.

Sigh ... I miss my Leroy set. Life was so simple back then.

[Pointdump]

Hi Liesl,

Dave P's advice is sound. During _MAPEXPORT choose Select Attributes >> Properties >> AREA:

Dave S

[parkr4st]

Clarifying my typo:  name the target OW_Field  Should be name the target field     OW_Area

There are also fields for WET, BOG, FEN, etc.

Where do those areas exist?  It appears as the data structure may need tweaking and allow some calculations.

Can you provide some of that data?

Dave P

[Anonymous]

Thanks for the replies, everyone.

Unfortunately when I used MAPEXPORT I do not see the attributes. (AREA, etc.) I am doing something wrong in setting up the SHP file initially, by the looks of it.

I am going to bite the bullet and buy some training on SHP file import and export from Autodesk because I have countless clients asking for this stuff now and I am having to turn people away because I just can't get it to work.  :'-(

[parkr4st]

if the end user is using ArcMap you do not need to calculate the area, only provide a field in the data table for the area.  ArcMap easily calculates area in the data table. 

Before you spend any money look at the tutorials in Map3D help.  Everything you need is already provided.

You can also provide your data table needs as I asked for and it likely you will receive more help here than with what you pay for:)

dave

[ChicagoLooper · Accepted solution]

Regardless of how you acquire or determine the square meters of the impacted wetlands, you'll have to draw the property boundary accurately. I can tell from your upload in post 3 that the site boundary is incorrect. You can view the property by using the Map Viewer >>HERE<<. In the upper right change the Base Map using the dropdown from World Topographic Map to Satellite View then click the Show Layers icon from the Add Data tab in the ribbon. Zoom in to the vicinity of the site then check Cadastral and Land Ownership in the Map Layers panel on the left. If you can't see the property boundary you are zoomed out too far.

From the Annotate & Print tab, use Export Map Image to create and save a Geotiff. Take the saved image and insert it to you map using FDO connection. Unfortunately, the FDO doesn't recognize the geotiff's coordinate system and will display the CS as 'unknown.' Use Edit Coordinate System in the FDO palette and assign WGS84.PseudoMercator (EPSG 3857) to the geotiff. Your drawing should have CANA83-10TM115-EAP assigned to modelspace, and if it does, the geotiff will position itself accurately when you add it using the FDO. Turn on Bing Aerial Maps to verify the geotiff's location. Turn off Bing Maps once verified. Use a polyline to trace the outline of the property boundary.

Redraw the wetlands. To ascertain the 'impacted wetlands' draw only the portions of the wetlands that fall 'inside' the property boundary. It's OK if you 'cut-off' the wetland parts that extends beyond the property. If any wetland extends off-site, then the prop boundary will be directly on top that edge of the wetland line where it get cut-off. You are only concerned about wetlands within the property, hence the term 'impacted wetland.' Outside portions will not be touched.

Once you have drawn all three polygons, i.e. property boundary, wetland 1 and wetland 2, you'll need to attach object data to them. Then you'll export the polygons to a shapefile. The shapefile's attribute data will inherit the object data. The instructions to create object data and to export your line work to shapefile are in the attachment. Follow exactly as written and you'll be fine. For instructions, see attachment.

[parkr4st]

The data is attached.

[parkr4st]

Trying again.  the file should make it this time:)

All the data is in one table.  drag and drop the .layer file into a map.

dave