Estimate Storage Capacity with Drone Imagery

The Yucaipa Valley Water District needs to estimate the storage capacity of a storm water retention basin. On-site measurements cost time, money, and labor, so the district captured aerial imagery with a drone to help estimate the basin's volume.

In this lesson, you'll convert drone imagery into elevation layers using Drone2Map for ArcGIS. Then, using ArcGIS Pro and ModelBuilder, you'll create a geoprocessing model to estimate the basin's volume.

Requirements

• Drone2Map for ArcGIS
• ArcGIS Pro
• ArcGIS Spatial Analyst extension
• Publisher or Administrator role in an ArcGIS organization (get a free trial)

Create the data

The Yucaipa Valley Water District (YVWD) took aerial imagery of their recycled water facility using a drone. In this lesson, you'll use Drone2Map for ArcGIS to convert the imagery into the following data products:

• Orthomosaic: An image composed of many smaller images aligned together
• Digital surface model (DSM): An image that shows the elevations of an area, including structures and vegetation
• Digital terrain model (DTM): An image that shows the ground elevation of an area, not including structures and vegetation

These datasets will provide an accurate map of the facility and 3D data necessary for calculating volume.

Download the drone imagery

The images that the drone captured are stored online in a zipped file folder. You'll download the folder, unzip its contents, and look at some of the images before you add them to a Drone2Map project.

1. Download the yvwd-images folder.
2. Locate the downloaded file on your computer. Right-click the file and extract it to a location where you can easily find it, such as your Documents folder.
3. Open the folder.

   

   The folder contains 19 images.

4. Double-click the image named DJI_0984.

   A preview appears. The image shows a top-down view of the storm water retention basin that you'll measure later. From this image, it's difficult to tell how deep the basin is.

   

5. Close the preview.

Create a Drone2Map project

Next, you'll create a new project in Drone2Map and add the drone images to a map.

1. Open Drone2Map for ArcGIS.

   Note:

   If you don't have Drone2Map, you can sign up for a free trial.

2. Sign in using your licensed ArcGIS account.

   Note:

   If you don't have an organizational account, you can sign up for an ArcGIS free trial.

   The application opens. You can choose from several project templates based on the type of data you'll create. Your data will be primarily 2D.

3. For Select Project Template, click 2D Full and click Next.

   

   Next, you'll specify some of the project's parameters and choose the images to use in the project.

4. For Give Your Project a Name, type YVWD Recycled Water Facility.
5. Click Browse to choose the location on your computer where the project data will be stored.
6. Click Add Folder.

   

   The Browse for Image Folder window appears.

7. Browse to and select the folder that contains your images.

   The images are loaded into the table.

   

   Each image has a Lat [Y] (degrees latitude), Long [X] (degrees longitude), and Alt [Z] (height) attribute. These geographic attributes were stored by the drone when it captured each image, allowing the images to be located on a map. For these images, the default coordinate system is acceptable.

8. Click Create.

   A map is created with 19 points, representing each image. The points are connected by orange lines, representing the flight path.

   

Process the data

To convert the images into data products, you need to process them. Because you chose the 2D Full template, processing the images will automatically create an orthomosaic, a DSM, and a DTM.

1. On the ribbon, click the Home tab. In the Processing group, click Start.

   

   The processing begins. It may take over 30 minutes to complete.

   Once the processing finishes, three new datasets are added to the Contents pane: an orthomosaic, a DSM, and a DTM. The datasets are also added to the map. Currently, you can only see the orthomosaic.

   

2. In the Contents pane, uncheck Orthomosaic.

   

   The DSM is now the visible layer.

   

   Note:

   Your layers may have been added in a different order so that the DSM is below the DTM.

3. Uncheck Digital Surface Model.

   The DTM is now the visible layer.

   

   The two DEM products look similar to one another, but the DSM has some extra processing to define the edges of buildings and vegetation.

4. Close the Processing Log and click the 3D Map tab.

   

5. Explore the three information products in 3D.

   Tip:

   For help with exploring 3D scenes, refer to the Navigation help topic.

   

   The imagery and DEM products appear to be sunken in the ground because the DTM used as the primary elevation surface only covers a small area. Outside of the study area, the WorldElevation3D/Terrain3D surface is used instead.

   The difference in elevation between the two surfaces is due to a difference in resolution. The DTM (which appears sunken) is the more accurate surface.

You've converted drone imagery into three different data products: an orthomosaic, a DSM, and a DTM. Next, you'll create a geoprocessing model to estimate the volume of the basin.

Estimate volume

Each year, Yucaipa Valley Water District cleans out its storm water retention basin to get ready for the next rainy season. Your next goal is to calculate the basin's total capacity. To do so, you'll create a model using geoprocessing tools in ArcGIS Pro.

Open the project in ArcGIS Pro

You can convert your Drone2Map project to an ArcGIS Pro project.

1. If necessary, open your YVWD Recycled Water Facility Drone2Map project.
2. Click the 2D Map tab.
3. In the Contents pane, turn on the Orthomosaic and Digital Surface Model layers.
4. Save the project.
5. On the Analysis tab, in the Tools group, click Open in ArcGIS Pro.

   

6. On the Open in ArcGIS Pro window, click Yes.

   ArcGIS Pro opens.

   Note:

   If you don't have ArcGIS Pro, you can sign up for an ArcGIS free trial.

7. If necessary, sign in using your licensed ArcGIS account.

   All of the elements that were present in your Drone2Map project are now present in your ArcGIS Pro project.

   

Fill sinks with a geoprocessing model

The process to estimate volume based on the DTM and DSM will require many geoprocessing tools. You'll organize these tools by creating a model in ModelBuilder. A model runs multiple geoprocessing tools in a sequence and can be reused for different datasets.

The first tool you'll add is the Fill tool. This tool removes sinks from elevation data. Sinks are areas where the elevation is lower than all areas around it—basically, anywhere that water will flow into and won't be able to flow out of. The storm water retention basin is a sink. By filling it, and then comparing the filled elevation to the basin's original elevation, you'll be able to determine the volume.

1. On the ribbon, click the Analysis tab. In the Geoprocessing group, click ModelBuilder.

   

   The Model view appears. It's currently empty. The ModelBuilder tab becomes available on the ribbon.

2. On the Analysis tab, in the Geoprocessing group, click Tools.

   The Geoprocessing pane appears. You can use this pane to search for tools.

3. In the search box, type Fill. Drag the Fill tool onto the model.

   

   In the model, the tool has two components. One, Fill, is the tool itself. The other, Output surface raster, is the layer the tool creates. Next, you'll configure the tool's parameters.

   

4. On the model, double-click the Fill tool.

   The tool parameters appear. The main parameters are the input layer and output layer. The third parameter, Z limit, is optional.

   Note:

   This lesson won't go over every parameter in each tool. To learn more about a parameter, point to it and then point to the information icon that appears next to it.

5. For Input surface raster, choose [ELEVATION_SURFACE]\DTM. For Output surface raster, change the output name to Fill_Result.

   

6. Click OK.

   In the model, the input layer is added. All three components change color, indicating that the tool can be run.

   

7. In the Geoprocessing pane, search for the Cut Fill tool. Drag it onto the model.

   Note:

   You can use the Cut Fill tool from either 3D Analyst Tools or Spatial Analyst Tools.

   The Cut Fill tool will calculate the volume change between two surfaces: the DTM before and after the Fill operation.

8. On the model, double-click the Cut Fill tool to open it.
9. For Input before raster surface, choose YVWD Recycled Water Facility_dtm.tif.
10. For Input after raster surface, choose Fill_Result.
11. For Output raster, change the output name to Volume_Raster.
12. Leave the Z factor parameter unchanged and click OK.

    

13. On the model, right-click Volume_Raster and check Add To Display.

    

    This option ensures that the Volume_Raster layer will appear on the map after the model is run.

14. On the ribbon, on the ModelBuilder tab, in the Model group, click Save

    

    The model is saved in the project's default toolbox using the name Model. You can access the model from the Catalog pane by expanding the Toolboxes and YVWD Recycled Water Facility.tbx folders. You could later run the model again with a different DTM to calculate another basin's volume.

15. In the Run group, click Validate. Click Run.

    

    The model runs.

16. When the model is finished running, close the Model processing window.
17. At the top of the Model view, click the 2D Map tab.

    

    The Fill tool filled all of the depressions in the DTM elevation surface. The Cut Fill tool created the Volume_Raster layer, which identifies all of the areas that were filled with the color red.

18. In the Contents pane, right-click Volume_Raster and choose Attribute Table.

    The attribute table contains a field with volume measurements for each sink.

19. Right-click the column header for VOLUME and choose Sort Ascending.

    

20. Click the cell next to the top row to select it.

    

    The largest sink represents the storm water retention basin. The volume values are all negative numbers because when you used the Cut Fill tool, you subtracted the higher elevation from the lower.

21. In the Contents pane, right-click the Volume_Raster layer and choose Properties.
22. In the Layer Properties window, click Source.

    Under Data Source, the Vertical Units are set to Meter.

    

    This unit type indicates that the VOLUME field was calculated in cubic meters.

23. Close the Layer Properties window and the attribute table.
24. On the ribbon, on the Map tab, in the Selection group, click Clear.

    

Create a polygon feature class

Next, you'll add the Raster to Polygon tool to your model. This tool converts a raster dataset to polygon features. You'll run this tool on the Volume_Raster layer to create a feature layer that shows the boundaries of the basin.

1. Click the Model tab.
2. In the Geoprocessing pane, search for Raster to Polygon and add the Raster to Polygon tool to the model.
3. In the model, double-click the tool and change the following parameters:
   • For Input raster, choose Volume_Raster:2.
   • For Field, choose Value.
   • For Output polygon features, change the output name to Basin_Polygon.
   • If necessary, uncheck Simplify polygons.

   

4. Click OK.

   Next, you'll use the Join Field tool to join the volume value from the Volume_Raster layer to the basin polygon.

5. In the Geoprocessing pane, search for and add the Join Field tool to the model.
6. In the model, double-click the tool and change the following parameters:
   • For Input Table, choose Basin_Polygon.
   • For Input Join Field, choose GRIDCODE.
   • For Join Table, choose Volume_Raster:2.
   • For Output Join Field, choose Value.

   

7. Click OK.

   

8. On the model, right-click Basin_Polygon (2) and check Add To Display.
9. Validate and run the model.
10. When the model finishes, close the Model processing window and save the model.
11. Click the 2D Map tab.

    A polygon layer has been added to the map.

Filter the layer

Next, you'll filter the layer so the smaller sink features aren't visible. To do so, you'll create a definition query to show only the storm water retention basin feature. You'll need the basin's unique ID value to create the expression.

1. Click the large polygon in the middle to open its pop-up.

   The OBJECTID value is the basin's unique ID.

   

   Note:

   Your object ID value may differ from the ID in the example images. In the example images, the ID value is 3536. Make sure to use the ID value for your basin feature if it is different.

2. Close the pop-up.
3. In the Contents pane, right-click Basin_Polygon (2) and choose Properties.
4. In the Layer Properties window, click Definition Query and click New definition query.

   

   You will construct a query to filter the polygon data to only the one feature you are interested in.

5. Under Query 1, use the drop-down menus to construct the query Where OBJECTID is equal to 3536. Replace 3536 with the value you found in the pop-up.
6. Click Apply and click OK.

   

   The query is applied.

7. In the Contents pane, turn off the Project Data group layer and the Volume_Raster layer.

   The map shows one polygon feature on top of the imagery and DEM layers.

   

8. Save the project.

You've created a model with geoprocessing tools to estimate the volume of the facility's storm water retention basin. You also created a result feature layer with the estimated volume. Next, you'll symbolize the map, configure pop-ups, and share the results.

Share the results

Previously, you estimated the volume of the storm water retention basin. Next, you'll symbolize the basin and configure pop-ups to convey the most relevant information. Then, you'll share the results as a map package.

Style the layer

First, you'll change the polygon's style to an outline with no fill. That way, users will be able to see the imagery of the basin under the layer. You'll also turn off unneeded layers.

1. If necessary, open your YVWD Recycled Water Facility ArcGIS Pro project.

   You intend to share the map as a package, so you'll remove some unnecessary layers.

2. In the Contents pane, right-click the Map Notes group layer and choose Remove. Also remove the Topographic basemap layer, the DTM elevation surface, and the WorldElevation3D/Terrain3D elevation surface.
3. Uncheck every layer except Basin_Polygon (2) and Orthomosaic.

   Next, you'll rename the basin layer.

4. Click the name of the Basin_Polygon (2) layer once to select it. Click it a second time to make it editable. Change the name to Retention Basin and press Enter.

   

5. Click the symbol under Retention Basin.

   The Symbology pane appears.

6. If necessary, at the top of the Symbology pane, click Gallery.
7. In the list of symbols, click the Black Outline (2 pts) symbol.

   Tip:

   To see a symbol's full name, point to it.

   

   The map updates.

   

   The basin is symbolized with an outline so users can see the imagery.

8. Close the Symbology pane.

Configure pop-ups

When you looked at the pop-up earlier, it contained a lot of information that isn't necessary for the YVWD staff to see, such as the feature's ID. Also, the volume value was negative and its unit of measurement wasn't clear. You'll configure the pop-up so that only the basin's area and volume are shown.

1. In the Contents pane, right-click Retention Basin and choose Configure Pop-ups.

   The Configure Pop-ups pane appears. Pop-ups can be configured using expressions. You'll use an expression to convert the area and volume values into the units requested by YVWD.

2. At the bottom of the Configure Pop-ups pane, click Expressions.

   .

3. Click New.

   The Expression Builder window appears. First, you'll add an expression to display the area of the basin in thousands of square feet.

4. For Name, type Area. For Title, type Area.
5. For Expression, type (or copy and paste) ($feature.AREA*10.7639)/1000.

   

6. Click OK.

   Next, you'll add an expression to show the volume in millions of gallons. This expression will need to do three things: convert from cubic meters to gallons, divide by 1,000,000, and multiply by -1 to make the number positive. You'll use text later to explain the units.

7. In the Configure Pop-ups pane, click New.
8. For Name and Title, type Volume.
9. For Expression, type ($feature.VOLUME*-264.172)/1000000. Click OK.

   Both expressions are configured. Next, you'll add the expressions and relevant text to the pop-up.

10. In the Configure Pop-ups pane, click the Back button.

    

    First, you'll change the pop-up title.

11. Click {Id} to edit the title of the pop-up.

    

12. Under Title Options, replace the existing text with Stormwater Retention Basin Capacity. Click the Back button.

    Currently, the pop-up content is a list of attribute fields. You'll change it to text that you can customize.

13. Click the Text button.

    

    A Text object is added to the list of pop-up elements.

14. Next to the Text object, click the Edit pop-up element button.

    

15. Type Area = followed by a space.
16. Click Field and choose Area {expression/Area}.

    

17. Add another space and type thousand square feet.

    Together, it reads Area = {expression/Area} thousand square feet.

18. Press Enter. On the next line, create the string Volume = {expression/Volume} million gallons.

    

19. Click the Back button.

    Now that you have formatted the pop-up to include the most relevant information, you no longer need to show all of the fields.

20. Next to Fields(11), click the Remove pop-up element button.

    

21. On the map, click the polygon feature to view its new pop-up.

    

    The retention basin has an area of almost 43,000 square feet and a capacity to hold over 1.4 million gallons of storm water.

    Note:

    Your values may be slightly different.

22. Close the pop-up and the Configure Pop-ups pane. Save the project.
23. If necessary, close Drone2Map.

Publish the map

Your map has been symbolized and its pop-ups are configured. Next, you'll publish your results as a map package to ArcGIS Online, where you can share it with the YVWD staff.

1. On the ribbon, click the Share tab. In the Package group, click Map.

   

   The Package Map pane appears.

2. For Name, type YVWD_Recycled_Water_Facility. For Summary, type This map shows the Yucaipa Valley Water District's recycled water facility and stormwater retention basin capacity.
3. For Tags, type Yucaipa, stormwater, and basin.

   

4. If necessary, for Share with, check the box next to your organization.

   You'll analyze the data before sharing it to make sure there are no major errors.

5. At the bottom of the Package Map pane, click Analyze.

   No errors or warnings are found.

6. Click Package.

   After a few minutes, the map is successfully packaged.

7. On the Package Map pane, click the Manage the package link to find the package in your ArcGIS Online account.

   

8. Close the Package Map pane.
9. Save the project.

In this lesson, you created several data products from drone imagery of a storm water retention basin and added them to an ArcGIS Pro project. Then, you created a model from geoprocessing tools to estimate the basin's volume. You configured the map and published it to ArcGIS Online.

You can find more lessons in the Learn ArcGIS Lesson Gallery.