Download the Lesson 8 data (Lesson8.zip [5]) and unzip it in your course folder.

1. Open ArcGIS Pro and start a new blank project called GEOG483_Lesson8 in your Lesson8 folder.
2. Add a new map and add the Lesson 8 data layers TransferStationsLACo, LandfillsLACo, AllRoadsLACo, and BoundaryLACo.
3. Open the attribute table for the roads layer.
4. Add a short integer field called Distance. [See Figure 8.1]
5. Save the changes you made to the table.
6. Calculate the Distance field so that all records have a value of 100.

Figure 8.1. Add a distance field.

C. Convert Vector Data to Raster Data

1. We now want to create a raster layer from the AllRoadsLACo vector layer. Open the Conversion Tools > To Raster > Feature to Raster tool.
2. Choose AllRoadsLACo as the Input features.
3. Choose Distance for Field.
4. Change the Output raster to Distance and make sure it is saved in your Lesson8 geodatabase. The path should look something like this (depending on the path or your data): C:\GEOG483\Lesson8\Lesson8.gdb\Distance.
5. Change the Output cell size to 100. This will create a new raster layer in which each cell will represent a ground area of 10,000 square meters. [See Figure 8.2]
   
   Figure 8.2. Convert to raster.
6. Click Run. The Distance raster layer will be added to the Contents pane. Close the Feature to Raster pane.
7. Using the same process as with the AllRoadsLACo vector layer, create a raster layer from the TransferStationsLACo vector layer. Choose OpStatus for Field. Change the Output raster to TransfStat_raster and make sure it is saved in your Lesson8 geodatabase. Keep the default Output cell size of 221.225555600002.
8. Turn off all of your other layers to see the raster layer you just created.

ArcGIS Pro Help:

Find out more about Cost Distance Analysis in the ArcGIS Pro Help. Click the View Help (question mark) button in the top right of the ArcGIS Pro window. Click SEARCH at the top of the page and type 
“cost distance”. Read through the first few results.

D. Calculating Cost Distance

1. In the Spatial Analyst > Distance toolbox open the Distance Accumulation tool.
2. Choose the TransfStat_raster layer as the Input raster or feature source data.
3. Choose Distance as the Input cost raster.
4. Enter CostDist_1 for the Output distance accumulation raster. (should look something like: C:\GEOG483\Lesson8\Lesson8.gdb\CostDis_1) Leave the other items empty.
5. Click Run. The task will complete, but there will be some warnings that say “Some sources are located on masked cells and will not be processed.” That is ok. The CostDis_1 layer will be added to the Contents pane. You just created a map that shows the distance from each waste transfer facility.
6. Open the Symbology for the CostDis_1 layer. Change Primary Symbology to Classify, change the number of Classes to 9. [See Figure 8.3]
7. Click the Analysis tab and click History to see the Geoprocessing History. You can see the various steps you have done so far. If you hover your mouse over the entries, you can see more detail.
   Figure 8.3. Cost distance results layer.

E. Prepare the Weighted Cost Raster Layer

Now that we have the distance calculated, we will add variation in moving along the different networks. To do so, we will take different road types into account.

1. 1. Open the roads attribute table. We are going to create a summary table that shows us how many features are in each road type.
   2. Right-click the RTTYP field and click Summarize. The Summary Statistics pane will open.
   3. The Input Table should be ALLRoadsLACo.
   4. The default Output Table name is fine (AllRoadsLACo_Statistics).
   5. Choose RTTYP for Field. Change the Statistic Type to COUNT. [See Figure 8.4]
      Figure 8.4. Finding the number of features of each road type.
   6. Click OK.
   7. Open the AllRoadsLACo_Statistics table that is added to the Contents pane. Remember that we used a look-up table in Lesson 5. We are going to turn this summary table into a look-up table.
   8. Add a Text field called Description with a Length of 25.
   9. Add a Short integer field called Cost.
   10. Save the changes to the table.
   11. Take a look at the Census page for Route Type Codes and Definitions [6].
   12. Populate the Description and Cost fields according to the table below. You can click each cell to edit the values. In this scenario, 100 represents the highest cost of moving along a surface (e.g. slowest – such as on a local road) and 1 represents the easiest and most-efficient movement along a surface (e.g. fastest – such as on an interstate). [See Figure 8.5]
       Figure 8.5. Populating the Description and Cost fields.
   13. 1. Join the AllRoadsLACo_Statistics table to the AllRoadsLACo using the RTTYP fields as the Input and Output Join Fields. Now, all of the records that had a value in the RTTYP field has a cost value associated with it. There are 54,817 features that don’t have a value in the RTTYP field. We will ignore those records since they are likely a type of “Other”.
       2. Export the joined layer (right-click on the layer and choose Data > Export Features) to a layer called AllRoadsLACo_cost.
       3. Change the symbology of the AllRoadsLACo_cost layer. This will help you see how the road type affects the layer created in the next section. If you change the symbology to Unique Values and use the Description field, you can make the Interstates, US Highways, Highways, and State Routes (in that order) most prominent. You may want to not display the Local and Other roads at all.

       F. Create the Weighted Cost Raster Layer

       1. We now want to create a second raster layer. There is a bug that prevents us from creating new raster layers in the same geodatabase after using the distance accumulation tool. We will create a new geodatabase. With the View tab selected, click Catalog Pane.
       2. With Project selected, right-click Databases and choose New File Geodatabase.
       3. Browse to your Lesson 8 folder where your Lesson8.gdb is located.  Create a new geodatabases –  L8costdistance. [See Figure 8.6]
          Figure 8.6 Adding a new geodatabase.
       4. Open the Feature to Raster tool.
       5. Choose AllRoadsLACo_cost as the Input features. Choose Cost for Field.
       6. For Output raster, browse to the lesson geodatabase called L8costdistance and change the layer name to Cost. The path should look something like this (note that you are creating the layer in one of the new geodatabases you just created): C:\GEOG483\Lesson8\GEOG483_L8costdistance.gdb\Cost.
       7. Change the Output cell size to 100. Click Run.
       8. Open the Distance Accumulation tool (Spatial Analyst > Distance).
       9. Choose the TransfStat_raster layer as the Input raster or feature source data.
       10. Choose Cost as the Input cost raster.
       11. Name the Output distance accumulation raster CostDist2. The path should look something like this: C:\GEOG483\Lesson8\GEOG483_l8costdistance.gdb\CostDist2. Leave the other items empty.
       12. Click Run. You will get the same warning as you did the first time you ran this tool. That is OK. The CostDist2 layer will be added to the Contents pane. Now, we have created a surface that shows how travel will likely change due to different road types. You can symbolize the layer the way you symbolized the first cost distance layer you created. Compare the two cost distance raster layers you created.

       Consider this:
       
       Can you see the difference between the two cost distance raster layers that were created? What caused the variations?

You have just completed Part I of this project, which involved doing a cost distance analysis. In Part II, you will experiment with some open source software.

Note:

Read the QGIS Help [10] for more information regarding coordinate reference systems and map projections. You can navigate to a good section by typing Coordinate Reference Systems (CRS) in the Search text box and double-clicking Coordinate Reference Systems.