National Water Information System: Mapper

Instructions: How To Use the Mapper

This interface provides a map view of the locations of sites with USGS water data. Google Maps are used to provide speed and versatility in a format that is familiar to many users. The interface can be used most efficiently by following a few basic rules:

Center and zoom to area of interest.
Select site types using checkboxes.
Sites are clickable only when zoomed in enough for accurate selection.
Specific areas such as US states and territories can be selected using the drop-down list.
Named places and addresses can be selected using Google geographic searching.

Important: Drawing areas with many sites will take extra time. For example, dense networks of ground-water sites may take several minutes to draw.

Selecting Context of Sites to Include

The National Water Information System (NWIS) provides access to data at over 1.5 million sites. Sites may be active or inactive. Some active sites provide real-time water data. The active/inactive status is determined by local USGS Water Science Centers. In most cases, sites designated as active will have current water data, but in some cases a site may also be considered active if it is part of an ongoing data-collection prgram. This control allows a user to select a broad category of sites to view, and is useful for simplifying a view in areas with a high density of sites. The default selection is All sites.

Selecting an Area or Place to View

The Mapper provides several alternatives to selecting an area to view. The Navigation Controls explained below can be used to select areas directly on the map. The default selection is the lower-48 United States.

One alternative is to select a particular U.S. State or other territory by name from a list on the top menu bar. This option is useful for quickly viewing a larger area. The map view will be centered on the area and include at least all area inside its official boundaries. Certain areas outside of US territory are also included in the list because some sites are operated as part of cooperative agreements.

Another alternative is to select an area using a place name or address. This option utilizes the proprietary Google geographic searching, and is useful for viewing close to a specific point of interest.

Displaying Sites

Explanation below is for zoom levels in which sites are not clickable.

Surface‑Water Sites
(streams, lakes, wetlands, estuaries, ocean, diversions, outfalls)

Any data (not clickable)

Ground‑Water Sites
(wells, any subsurface)

Any data (not clickable)

Spring Sites

Any data (not clickable)

Atmospheric Sites
(climate, weather)

Any data (not clickable)

Other Sites
(facilities, water use, any other)

Any data (not clickable)

Explanation below is for zoom levels in which sites are clickable.

Surface‑Water Sites
(streams, lakes, wetlands, estuaries, ocean, diversions, outfalls)

Any data

Multiple surface-water sites

Ground‑Water Sites
(wells, any subsurface)

Any data

Multiple ground-water sites

Spring Sites

Any data

Multiple spring sites

Atmospheric Sites
(climate, weather)

Any data

Multiple atmospheric sites

Other Sites
(facilities, water use, any other)

Any data

Multiple other sites

The Mapper displays clickable sites only at smaller scales (zoom level 11 or greater) in the map view. This approach provides a reasonably fast drawing time. The display of each of the site types can be turned on and off using the checkboxes.

Shapes and colors are also used to indicate the type of data collected at sites. Black triangles represent surface-water sites, red circles represent ground-water sites, blue circles represent springs, blue squares represent atmospheric sites, and inverted gray triangles represent all other site types.

At some locations there are multiple sites. These are indicated by a Multiple Sites mapping symbol.

The full explanation of symbols for a site type will only appear when that site type is turned on.

Selecting a Site and Getting Data

Controls in this section only apply at zoom levels of 11 or greater where sites are clickable.

Selecting (clicking) the site will identify it by site number and name. A link is also provided to access any available data from the National Water Information System. Multiple links are provided in cases where there are multiple sites at one location.

A List Sites button is provided in the left control panel. Selecting this control will produce a new window that lists all sites included in the map view. The list can be printed or saved to a file, and includes links to access any available data from the National Water Information System. The list also includes the creation date, time, bounding coordinates, and other information about the map view.

A View KML button is provided in the left control panel. Selecting this control will produce a new window that lists the Keyhole Markup Language (KML) code for all sites included in the map view. KML can be imported into geographic browsers such as Google Earth for viewing outside of the NWIS Mapper or for use in custom applications. The list can be saved to a file, and includes links to access any available data from the National Water Information System.

A Cancel Drawing button is provided in the left control panel. Selecting this control will interrupt drawing of sites in the map panel. This control is used when many sites are being displayed and the drawing time is excessive. Using this control does not impact use of List Sites or View KML, and all sites that would have been drawn are included in the results from those controls.

Background View

The default background view is a shaded relief terrain map. Several background map types are available and can be selected:

Map - This shows a map with a traditional depiction of roads, parks, borders, bodies of water and more.
Satellite - This shows aerial imagery.
Hybrid - This shows a modified composite of the Map and Satellite views.
Terrain - This shows physical elevation as shaded relief and elevation lines. It also includes street names and other information.
USGS - This shows USGS topographic map.

Note that background views are appropriate to and will vary with map scale. Not all views are available at all scales, particularly when zoomed in very close to a location.

Navigating in Google Maps

You can navigate (move your view) in two dimensions in any Google Map. To pan (move the map), do one of the following:

Click and hold the mouse buttons to drag the map
Press the up arrow on your keyboard to move north
Press the down arrow on your keyboard to move south
Press the right arrow on your keyboard to move east
Press the left arrow on your keyboard to move west

Additionally, you can zoom in or out pressing the + or - keys. Move the cursor over a location and use the mouse scroll button to zoom in or out on that location. To center and zoom in on a location, double click the location.

Using the Navigation Controls

On-screen navigation controls are shown on the left. Navigation controls include:

Arrows - Click the appropriate arrow buttons to move the view north, south, east or west. Click to return to your original view.
Zoom - Click + to zoom in on the center of the map. Click - to zoom out.
Zoom slider - Drag the zoom slider up or down to zoom in or out incrementally.

Zoom Box	Click to activate zoom-box function. The following control will appear.
Drag Box on Map	This control appears when Zoom Box is active. Drag the box corners to desired zoom area. Note that the zoom box height and width will be proportional to the map window.
Previous Zoom	This control appears when Drag Zoom has been completed. Click to return to previous zoom view.

Using the Overview Map

The overview map (shown left here) appears in the bottom right corner of the map. It helps orient you by showing the location of current map view in the context of a larger geographical area. The area currently displayed in the map is show as a purple box in the overview map. At any time, click to hide the overview map or click to display it again.

As you pan or zoom in the map, the overview map view changes accordingly. You can change the existing view in the map by doing one of the following:

Drag and drop the purple box in the overview map.
Drag and drop the area outside the purple box to pan the map.

Accessibility FOIA Privacy Policies and Notices

U.S. Department of the Interior | U.S. Geological Survey
URL: http://wdr.water.usgs.gov/nwisgmap/instructions.html
Page Contact Information: NWIS Mapper Team
Page Last Modified: 18 August 2009