In HEC-RTS, layers function like stacked transparencies, each displaying different types of information. These layers may include physical features such as roads, county and state boundaries, rivers, and subbasins, all shown as color images in the map window. Each image, along with its associated data, is considered a layer.
Layer Types
There are two types of layers:
Primary layers are automatically generated when a new watershed is created and are present in all HEC-RTS watersheds, though some may be empty depending on the watershed. These layers are module-specific and are created when certain elements, like stream alignments, time series icons, map window elements, and gridded precipitation data, are added. A primary layer is also generated when a forecast alternative is selected for computation. Primary layers can contain sub-layers. For example, the Time Series Icons Layer can have multiple user-defined sub-layers representing different types of data, such as flow and precipitation.
Map layers are optional layers to help visualize the watershed, and HEC-RTS supports various formats including online maps (e.g., Google Street Maps).
Layer Scaling
You can control the visibility of map layers based on the zoom level in a map window. This feature helps reduce clutter when viewing the entire map and allows more detailed information to appear as you zoom in.
Examples of useful customizations:
Show time series icons for less significant gages only when zoomed in.
Make detailed map layers visible at closer zoom levels.
Display rasters or other background images only when zoomed in.
Additional Resources
Refer to this guide for more information on working with layers in HEC-RTS.