A map layer in HEC-RTS is a visual overlay that shows different features of your watershed. These layers appear as color images on the map and help you see and understand the geography of your watershed.

This guide walks you through how to use map layers in HEC-RTS to visualize watershed features more effectively.

Accessing the Map Layers Dialog

You can open the Map Layers dialog from any tab in HEC-RTS:

  1. Go to the Maps menu and click Map Layers.
  2. The Map Layers dialog will appear.

Adding Map Layers from a File

To add a map layer:

  1. In the Map Layers dialog, go to the Layers menu and select Add Maps.
  2. In the Select Map to Add dialog, browse to the folder containing the map file.

  3. Select the desired file. The Create Copy checkbox is enabled by default, which copies the map into the active watershed’s maps folder.
  4. Click Open. The map layer will be added to the map window and listed in the Map Layers tree.

Removing Map Layers

To remove a layer from your watershed:

  1. In the Map Layers dialog, go to the Layers menu and select Remove Map Layer.
  2. In the Remove Map Layers from Watershed dialog, select the map layer you want to remove from the watershed.  

  3. Click Remove.
  4. Click Yes to confirm the action in the confirmation window.
  5. The layer will be removed from the map and the Map Layers tree.

Adding Internet Background Maps

HEC-RTS allows you to add preloaded online background maps:

  1. Go to the Maps menu and select Internet Maps.
  2. Choose from the available map types:
    1. Google Street Map
    2. Google Satellite Map
    3. Google Terrain Map
    4. Bing Satellite Map
    5. Open Street Map

The selected map will be added as a background layer.

Editing Map Layer Properties

To modify a map layer's appearance:

  1. In the Map Layers dialog, right-click the layer you want to edit.

  2. From the shortcut menu, select Properties.

  3. The properties dialog varies by map type. For example, selecting a polygon shapefile opens the Edit Polygon Properties dialog, where you can adjust fill colors, border styles, and labels.

Configuring Default Map Properties

To set default map settings:

  1. Go to the Maps menu and select Default Map Properties.
  2. The Default Map Properties dialog will open, containing two tabs:
    1. Map Extents 
    2. Default Map Layers 

Map Extents Tab

This tab allows you to control the visible area of the map.

Available commands are:

  • Coordinate System - Displays the coordinate system assigned to the watershed (view-only).
  • Extents (Easting and Northing) - Sets the bounding box for the map area.
  • Set Map Extents to Display - Updates the extents to match the current zoom level.
  • Grow to Map Extents - Automatically expands extents to include all watershed elements.

Default Map Layers Tab

This tab lists all map layers currently available in the map window. You can toggle visibility by checking or unchecking boxes next to each layer.