Texas A&M University, Department of Civil Engineering Instructor: Dr. Francisco Olivera CVEN 658 Applications of GIS to Civil Engineering USING THE MODEL BUILDER PRASHANT KRISHNAN, 12/04/06 Contents: Brief overview of the Model Builder Goals of the exercise Computer and data requirements Procedure: 1. Developing a model 2. Adding data (DEM) to the model 3. Fill 4. Flow Direction tool 5. Flow Accumulation tool 6. Single Output Map Algebra tool 7. Stream Links tool 8. Watershed tool 9. Convert Raster to Polygon 10. Stream to Feature 11. Validate and Run 12. Viewing reports and properties 13. View the tool 14. Adding the tool to another Map document Brief Overview of Model Builder Model builder is an interface within ArcGIS 9.2 that allows users to build a flow path for the data and processes required in obtaining the results for an analysis. Many analyses carried out have different types of data and multiple tools operating on the data. The model builder helps in channelizing these repetitive processes into sort of a - flowchart of data, tool used on it and the result obtained. The model builder is a user-friendly interface with a few easy to learn functions. In this exercise, the emphasis is on learning to create a simple model to understand the principles model building. Department of Civil Engineering 1 Texas A&M UniversityFull Zoom Select Copy Paste Extent Continuous Zoom out Zoom Save Copy Add data Zoom in Pan Navigate Run Print Auto Add Layout Connection The Model builder toolbar Goals of the exercise The goals of this exercise is to introduce you to the model builder. Computer and data requirements This exercise was successfully performed using ArcGIS 9.0- ArcMap and ArcToolbox. Download the zip file containing the data. Uncompress the zip file to a folder on your drive. Go to the folder in ArcCatalog and you see the Digital Elevation Model (DEM). The DEM is named dem. Procedure 1. Developing a model In this section of the exercise, you are going to learn how to add a toolbox to the ArcToolbox and adding a new model to this toolbox. 1) Open ArcMap from the start menu or from ArcCatalog. Save the new empty map document by clicking File/Save As. Now add the DEM (dem) to the data frame in the ArcMap document by using the Add Data tool. 2) Since we are working with raster data, it is important to activate the Spatial Analyst Extension. To make the extension active, click on Tools/Extensions. Check the Spatial Analyst box in the Extensions wizard that appears and then click Close. Insert a check to the Spatial Analyst in the Tools/Customize wizard to add the spatial analyst toolbar to the ArcMap document. Now set the Working Department of Civil Engineering 2 Texas A&M UniversityDirectory, Analysis Extent (same as layer “dem”) and the Cell Size (same a layer “dem”) by clicking on Spatial Analyst/Options. 3) Open ArcToolbox by clicking on the small red box on the standard menu of the ArcMap document. Once the ArcToolbox is active, right click on the ArcToolbox, and add a New Toolbox. A new toolbox is added to the ArcToolbox interface. Name this new toolbox as watershed-Delineation. 4) The next step is to create a new model. This can be done by right clicking the watershed-Delineation tool and adding a New/Model. A new model is added to your tool. Name this model as WSD. Department of Civil Engineering 3 Texas A&M University2. Adding Data (DEM) to the Model In this section of the exercise, you will learn how to add data to your newly created model. First, you will open the model builder window and secondly add your data to this window. 1) Right click on the model WSD and select Edit. A new window opens; this is the Model Builder window. 2) Click on Add Data and direct the path to the folder containing the layer dem. Add the layer to the model. The layer will look like a blue bubble with the name of the layer in the center of the bubble. Department of Civil Engineering 4 Texas A&M University3) Alternatively, the dem layer can also be added by dragging the layer from the ArcMap document to the Model Builder window. Right click on the dem bubble and enable the Model Parameters. 3. Fill In this section of the exercise, you will add the Fill tool and connect it to the dem layer. 1) In the ArcToolbox, open the Spatial Analysis/Hydrology toolbox. Drag the Fill tool to the model builder window. Two bubbles will be formed on the model builder window. One bubble will be called by default Fill and the other Output raster. Initially the two bubbles will have no color. 2) Using the connector tool connect the dem bubble with the Fill bubble. Automatically the Fill tool will turn Yellow and the Output raster will turn Green. 3) Double left click the Fill tool and check to see if the input raster field has been populated with the dem raster. Change the name of the output raster by clicking on the Browse tab and directing it to the working directory, call this output raster as Fill_dem, and select ok. Department of Civil Engineering 5 Texas A&M University4) You will notice that the Green bubble is no more called Output raster but is called Fill_dem. Right click on the Fill_dem layer and enable Model. Parameters and Add to Display.. 4. Flow Direction tool In this section of the exercise, you will add the Flow Direction tool and connect it to the Fill_dem layer.. 1) In ArcToolbox, open the Spatial Analysis/Hydrology toolbox. Drag the Flow. Direction tool to the model builder window. Three bubbles will be formed on the. model builder window. One bubble will be called by default Flow Direction, the. second one will be the Output drop raster, and the third one will be the Output raster.. 2) Using the connector tool connect the Fill_dem bubble with the Flow Direction bubble. Automatically the Fill Direction tool will turn Yellow and the Output . raster will turn Green. The Output drop raster will still have no color since you . are not using another layer as the Output drop. In this exercise you will not be . adding any Output drop rasters so let the Output raster bubble remain uncolored. . Department of Civil Engineering 6 Texas A&M University3) Double left click the Flow Direction tool and