Calculate the mean contour elevation for contours intersecting a cross-section in ArcGIS Pro

Summary

In ArcGIS Pro, calculating the mean contour elevation for contour lines that intersect a cross-section provides a quantitative summary of terrain elevation values represented by the contour features. This article provides the workflow using the Spatial Join and Summary Statistics tools. Spatial Join is used to associate contour elevation values for each cross-section based on the intersection, while Summary Statistics is then used to calculate the mean of the contour elevation field for each cross-section. This approach supports the comparisons of elevation characteristics represented by different cross-sections and applications such as route evaluation, site assessment, and terrain analysis.

Procedure

1. Open the project in ArcGIS Pro.

Note:
Ensure the cross-section layer has a unique identifier field. Refer to ArcGIS Pro: Unique identifier fields for more information.

2. On the ribbon, click the Analysis tab. In the Geoprocessing group, click Tools.
3. In the Geoprocessing pane, search for and select the Spatial Join tool.
4. Configure the Spatial Join tool.
1. For Target Features, select the cross-section layer from the drop-down list. In this example, ‘Levelling’ is selected.
2. For Join Features, select the contour layer from the drop-down list. In this example, ‘Contour’ is selected.
3. For Output Feature Class, specify a name and location. In this example, ‘Levelling_SpatialJoin’ is specified.
4. For Join Operation, click the drop-down menu and select Join one to many.
5. Click Run.

5. On the ribbon, click the Analysis tab. In the Geoprocessing group, click Tools.
6. In the Geoprocessing pane, search for and select the Summary Statistics tool.
7. Configure the Summary Statistics tool.
1. For Input Table, click the drop-down menu and select the join layer created using the Spatial Join tool.
2. For Output Table, specify a name and location. In this example, ‘Levelling_Spatial_Statistics’ is specified.
3. Under Statistics Fields, for Field, click the drop-down menu and select the field containing the contour values. In this example, ‘Height’ is selected. For Statistic Type, click the drop-down menu and select Mean.
4. For Case Fields, click the drop-down menu and select the unique identifier field of the cross-section layer. In this example, ‘LvlName’ is selected.
5. Click Run.

8. In the Contents pane, under Standalone Tables, right-click the newly created table and select Open.

The attribute table below displays the mean contour elevation for each intersecting cross-section.