There are three basic components to the Tualatin River Watershed Information System.
Each of the components can be easily navigated to find the appropriate
information you are interested in, and each component is essentially linked
at the Theme level. That is, you can easily jump from one window to the
next displaying information about one specific data layer in each window.
The data layer browser essentially acts as a file explorer in which you can view the directory structure of the information and select specific data layers to map or view information about. The map viewer is made for rudimentary viewing and querying of individual or multiple data layers (up to 10) and the text viewer (web browser) allows for the viewing of hypertext documents associated with data layers or general information.
The data in the Tualatin River Watershed Information System are geographic information system (GIS) data layers, available in the industry standard ESRI shapefile format. All data layers have both attribute information and associated metadata. Both geographic and attribute information associated with specific data layers can be accessed by "right-clicking" or selecting "layer" from the drop down menu after selecting (highlighting) the desired data layer in the "tree" view to the left. Data layers are organized according to subject, as described in the subject directory under Data Structure pages. In most cases, users can browse metadata, view a thumbnail image or interactively map, identify or query specific data layers using the map viewer. All of these functions can be accessed by selecting or highlighting a data layer in the tree view to the left. You can not use the data layer browser to move data around or add or delete data layers to the data structure. You must use your file manager or windows explorer to perform such functions.
The custom map viewer provided with the Tualatin River Watershed Information System can be used for rudimentary viewing, querying and identification of specific data layers and features. For additional spatial analysis capability we recommend using a more sophisticated GIS software package such as ESRI's ArcView or Arc/Info. Although the data layer viewer provided is not a fully functional GIS it does offer the user the ability to access GIS information without actually posessing or purchasing expensive GIS software. The map viewer contains the following functionality:
Use the pan and zoom tools to change the extent or zoom in or out based on interactive events.
You can use the full extent button to zoom to the extent of the watershed.
Use the identify tool to list the attributes of a specific feature in any theme. The identify tool works interactively where you can click on the feature in the map viewer you wish to identify and view the results in a pop up window. The tool identifies features of the Theme listed at the top of the legend. If no feature is associated with the Theme the tool will identify features based on the Theme listed next in the legend and so on.
Click on the search button to search for features in any Theme based on specific attributes. A pop up window will appear which will give you the option of choosing which theme to search and which item to search for. You then must enter the search string in the appropriate text box.
There are several ways to add a data layer or "Theme" to the map viewer. The easiest way to do so is to highlight a data layer in the data layer browser and right click on your mouse to bring up the "view" dropdown menu (or you can highlight the theme and click on the "View" drop down menu from the menu bar). Choose "Map" from the menu and the map viewer will automatically open, displaying the data layer you had highlighted. You can also open the Map Viewer by choosing "Open Map Viewer" from the File drop down menu.
If you are working in the map viewer you can add a data layer by clicking on the add theme button or by choosing "Add theme" from the View pull down menu. A dialog box will appear allowing you to choose any shape file from the Tualatin subject directories. You can also select a data layer from the data layer browser and drag and drop it into the map viewer legend area.
Once you have a layer added to the map viewer you can manipulate how it displays. The majority of a "Theme's" properties can be manipulated by right clicking on the name of the "Theme" in the legend. To turn a theme on or off you merely click the checkbox next to the name of the theme in the legend. Themes will display in the order in which they appear in the legend, therefore Theme names at the top of the legend will appear on top in the map viewer. This is important to understand because you will often want point and line themes to appear on top in the map viewer (polygon themes will cover up in information underneath the extent of the polygons).
You can change how a Theme appears in the map viewer by right clicking on it and choosing "Properties" from the drop down menu. The Theme Properties dialog box will appear and you can change the color of the draw symbol, label the Theme based on certain attributes or classify the Theme based on different attributes. You will often want to classify Themes to display different features based on different values in specific attributes.
Most of the metadata on this information system is in FGDC format. You will want to access the metadata on a regular basis. Often, for example, you will be unable to interpret codes in the attribute tables or you may want to know what date a particular data set was created. Anything you want to know about any dataset can be accessed easily and at any time. The easiest way to access metadata is to highlight the data layer in question in the data layer browser to the left and right click on your mouse to bring up the theme drop down menu. Choose metadata from the menu and the associated metadata will appear in this window. If you are searching or querying data from the map viewer, you merely click the Metadata button to access the metadata for the active theme.
As previously noted, most of the metadata exist as FGDC compliant html pages. Because FGDC format is composed of an abundant amount of information it is often difficult to find the information you are looking for unless you are familiar with the format. In most cases you will be looking for attribute descriptions. Fortunately each page is headed with a hyperlinked table of contents. To get to attribute descriptions either click on "detailed description" or "overview" of Entity and Attribute descriptions and find the attribute item you are interested in.
Each data layer also has a thumbnail associated with it. To get a quick glance of any data layer you merely select the data layer, right click on it and choose "Quick Glance" from the drop down menu. A GIF image will appear in this window.