The Create Viewshed tool uses the Esri Elevation Analysis service to identify areas that are visible from specified observer points.
The output is a hosted feature layer.
Example
A GIS analyst is performing a preliminary review of wind farm applications to determine which proposals should be submitted for further assessment. Her criteria are that the proposals must have road access and cannot be on or within view of protected areas. Create Viewshed can be used to determine which proposals are within view of the protected areas.
Usage notes
Create Viewshed includes configurations for the input layer, viewshed settings, and the result layer.
Input layer
The Input layer group includes Input observer features layer, which specifies the point features that will be used as the observer locations. You can choose a layer using the Layer button, or use the Draw input features button to create a sketch layer to use as the input. For feature inputs, a count of features is displayed below the layer name. The count includes all features in the layer, except features that have been removed using a filter. Environment settings, such as Processing extent, are not reflected in the feature count.
Viewshed settings
The Viewshed settings group includes the following parameters:
Observer height specifies the height of the observer locations above the ground.
Examples of observer locations include people and fire towers.
Observer height units specifies the measurement units for the Observer height parameter.
Target height specifies the height of the objects being viewed by the observer. This height will be added to the height of the terrain to establish visible areas.
Examples of objects being viewed include people, wind turbines, and the ground.
Target height units specifies the measurement units for the Target height parameter.
Maximum viewing distance specifies the maximum distance at which the computation of the visible areas will stop.
An example of the maximum viewing distance is how far a person can see given the weather and atmospheric conditions of the day.
The maximum value allowed is 31 miles (50 kilometers).
Viewing distance units specifies the measurement units for the Maximum viewing distance parameter.
Result layer
The Result layer group includes the following parameters:
Output polygon name is the name of the output viewshed feature layer that will be created.
The name must be unique. If a layer with the same name already exists in your organization, the tool will fail and you will be prompted to use a different name.
- Save in folder specifies the name of a folder in My content where the result will be saved.
Limitations
The following limitations apply to the tool:
- The input must be point features.
- The input has a limit of 1,000 features.
- The maximum viewing distance can be no more than 31 miles (50 kilometers).
- All observers must have the same height. All objects being viewed must have the same height.
- Visibility does not include obstructions such as trees and buildings.
Environments
Analysis environment settings are additional parameters that affect a tool's results. You can access the tool's analysis environment settings from the Environment settings parameter group.
This tool honors the following analysis environments:
- Output coordinate system
- Processing extent
Note:
The default processing extent is Full extent. This default is different from Map Viewer Classic in which Use current map extent is enabled by default.
Outputs
This tool creates an output feature service that represents the areas where the observers can see the observed objects. The frequency field records the number of observer points that can see each area.
Usage requirements
This tool requires the following user type and configurations:
- Creator, Professional, or Professional Plus user type
- Publisher or Administrator role, or an equivalent custom role
Resources
Use the following resources to learn more:
- Viewshed in ArcGIS REST API
- create_viewshed in ArcGIS API for Python