Adding GIS and DWG Data (8:14 min)

Adding GIS and DWG Data - Practice Exercise

Task 1: Import the GIS shape file data

1. Continue to build the Base Map drawing. Open the practice file, Base Map.dwg. It should be up to date with the data added from completing the previous exercise.
2. Use Windows File Explorer to browse to the GIS folder in the dataset.
3. Select the three .SHP files with the name pre-fix “Local”.  Note you can filter for files with .SHP extension.

4. Drag and Drop the three .SHP files onto the drawing canvas.
5. At the command line enter MAPWSPACE and answer ON. This will display the Map Task pane.
6. On the Display Manager tab the three new features are added to the already existing OrthoImage.

7. Select any one of the Local features and select Zoom to Extents from the Right Click menu.

8. Use the Geolocation tab to turn on the Bing Maps aerial imagery to confirm that our project and this new data is all in the correct location.
9. Turn off the Bing Maps imagery.

Task 2: Show Data Table and Validate Local Survey Benchmark

To validate the accuracy of our data, we will use the National Geodetic Survey government agency placed and maintained land survey benchmarks, and there are two very near our project.

1. Toggle on the OrthoImage and select Zoom to Extents from the Right Click menu.
2. Select on the Local USGS Control feature and select Show Data Table.

3. The Data Table shows a tabular form of all of the attribute information that is attached to each of the control points. You can see, as I scroll sideways, that there are many attribute fields for each of the records in this GIS point feature.
4. At the top of the Data Table panorama toggle off the Auto Zoom and toggle on Auto Scroll.

5. Arrange the display of the table so that the Control point near the lower right of the image is visible.

6. Click on the Control point and note that the Data Table automatically scrolls and highlights the row associated to that point location.
7. Select in the cell that shows the http link, this is the DATA_SRCE attribute field.

8. Copy-clip this web address and paste into an Internet browser and go to this web page.
9. The result shows us the data sheet as registered with the agency that is responsible for placement and maintenance of official land survey benchmarks. The positional accuracy, the description of the benchmark’s physical location, and the historical maintenance are all recorded on these sheets. Note: If you are unable to browse to this web page, please see the copy of it in the PDF folder of the Dataset. The file name is: NGS Data Sheet KK0556.pdf
10. Read the description of the location of this control benchmark near our project, note that it is 17.2 meters North East of a lamp post, 5.4 meters east of the paved road shoulder, and 3.7 meters west of a chain link fence. Now zoom in and check out this information compared to the OrthoImage.  Dismiss the data table and zoom to the point. Find the lamp post, and see that the point is North East of it, and West of the fence, and East of the roadway shoulder!

Task 3: Remove Local Road and Railway GIS Data

1. The Local Highways and Railways are not needed.  On the Display Manager tab select on the Highways feature and select Remove Layer from the Right-Click menu.

2. Select on the Data icon and select Connect to Data.

3.  On the Data Connection panel select Local Highways and highlight, right click and select Disconnect.

4. Select Local Highways again and select Delete. OK the Verify Delete Connection if it displays.

5. Repeat these steps to disconnect and delete the Local Railways feature.
6. Remember – the data connections that you see in this panel are is saved with the dwg file and if you share this drawing you must also share any connected data sources. If we look at the status of our Base Map dwg now we see that there are two connections that must be shared – the OrthoImage.tif raster image and the Local USGS Control shape file set.

Task 4: Add Survey Tie DWG Data

Returning to our dwg we will add the important tie information that links the GPS Drone control points to the USGS and NGS agency permanent benchmarks.

1. Use the XREF command to Attach DWG. Browse to the DWG folder of our data set and select the GPS Control Ties to NGS Tri Station.dwg  file.
2. If the land survey data is correct there is no scale, rotation, or insertion point adjustment needed. These boxes remain unchecked.

3. Zooming into the attached drawing notice that the drawing location is correct.
4. Use select to highlight to compare the location of the COGO points and the Xref drawing. Also check the benchmark, by toggling the Local USGS Control feature on and off in the Map Task Pane.

Task 5: Add Boundary Plat and Site Inspection Report DWG Data

1. Use XREF to attach the Boundary Plat dwg.  No adjustment of the scale, rotation, and insertion should be necessary. 
2. Check for accuracy by looking closely at the Tie information that links the boundary markers to the NGS Benchmark. Zoom into the Tie and then look at each of the endpoints to verify the accuracy.

1. Use XREF to attach the Site Inspection Report.dwg.  No adjustment of the scale, rotation, and insertion is needed.  Ths drawing  provides detailed information about the current status of significant features on the development site that may impact the development.
2. Unload the GPS Control Ties to NGS Tri Station.dwg to give a clearer view of the site and boundary details.

The Base Map can now be cleaned-up and prepared in the way you prefer. Perhaps you will bind the Xrefs, manage layers and styles, remove duplicate objects, publish documents, and such. It is all up to your project requirements.  You have added important existing conditions data and verified the positional accuracy. You have established good control points for the continued life of this project so it can be built on the correct position on Earth!

This finishes the “Beginning to Build the Base Map” course exercises and prepares you for the next course “Creating Surfaces from Point Cloud Data.”