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Indiana Department of Environmental Management

Nonpoint Source Water Pollution

Nonpoint Source > eServices > Indiana Water Quality Atlas Indiana Water Quality Atlas

The Indiana Water Quality Atlas (IWQA) is an on-line mapping application for watershed coordinators and others developing maps for planning purposes. The following information will help you navigate into and through the site features. This content is also available for download [DOC].

The startup screen of the Indiana Water Quality Atlas shows the distribution of the IDEM surface water monitoring data (referred to as AIMS - Assessment Information Management System) available for mapping through this application. From this screen the tools in the top left below the “IWQA” will help you navigate into and around the map extent, connect you with the Purdue University Long-Term Hydrologic Impact Assessment (L-THIA) modeling tools including the watershed delineator, provide you with print to file in various formats options, and offer the tools for uploading your own data layers into the map from zipped formatted files.

In the top right tools bar, you have: the base maps options which allow you to switch between the streets, USGS topographic quadrangle, or aerial imagery layers; the IWQA data layout options to work on multiple maps during a single session; the AIMS data list of layers (currently displayed at startup); the additional map layers along with the legend to show how it will be displayed; and 2 additional tools for a statewide overview and magnifying glass for specific areas in the map extent. All of these tools and features should be useful in the development of maps for your watershed planning and assessment purposes.

To begin using this application, zoom into the map using the navigation compass in the bottom left or the Zoom To (Globe) icon on the top left to select from lists by Watershed Code, Watershed Name, or County. If you select by a watershed name or code, the polygon for that selection is highlighted and the automatic zoom takes you to that extent. If you choose County, it auto zooms into and highlights the extent of that county. To further fine tune your extent, you may use your scroll to zoom in or out with your mouse wheel and click/hold the left mouse button to pan for best fit while menus are open.

Below is an example of using the Zoom to Watershed Code using 051202020702 which is the North Fork of Prairie Creek in the Lower West Fork White sub-basin. To turn on the labels for the watersheds, access the IWQA Data Legend icon on the top right tool bar and check box the HUC under Map Layers.

The slider bars next to each layer in the Map Layers box allows you to determine level of transparency for individual layers. This is especially useful when using overlays of polygons and imagery for some of the other maps you’ll need for your watershed management plan or other mapping needs.

Above is the tool bar with a few of the other IWQA Map layouts that go along with watershed management plan development. The default is General as shown here, however the default settings of the others offer a jump start for the additional data you may want to turn on or add from your own zipped collection of spatial data layers. Beneficial Areas refers to lands that your plan may wish to designate as high quality needing protection or other such consideration. Critical refers to the areas that need attention first or that could be shown by priority depending on the local data layer you wish to add. Flood Zone data is provided in this layout should your area need to address flooding issues. Land-use is preset with our current Land-use layer; however, more detailed information of land-use can be collected and calculate to your area through the L-THIA application. Running the L-THIA application is easily accessed through the top left dialog tool bar. Hover over the L-THIA button on the IWQA dialog tool bar. Verify L-THIA Delineation tool is visible to the right of the IWQA dialog. Click on the map where you want to delineate L-THIA data. New windows will pop-up with the Watershed Spatial Data Summary from the L-THIA site. To view the watershed in the map, press Download Data and save the ZIP file to a location on your computer. Then Press the Add Data button on the IWQA dialog (to the left), navigate to the downloaded ZIP file, select, and open the file. The shape of the Watershed will be added to the web mapping application. To clear the watershed from the map, press Clear Map from the Add Data dialog.

The additional instructions for using the L-THIA modeling tools are not provided here as they offer step by step walk though for watershed delineation and data options based on user prescribed details and offers downloads of the data to be included in the IWQA layouts. Assistance for using L-THIA is also available on the L-THIA site.

The Point Source layout is preset with the impaired waters and the AIMS, ICIS, and OLQ Map Layers can be check-marked to show sampling sites in relation to regulated facilities. With this application, you are free to mix and match Map Layers with IWQA Maps layouts and Base Maps choices to best represent your needs as you develop your plan. Take a few minutes to check out all of the layers, layouts and base maps first to help you plan for your mapping needs.

Layouts for creating map images to place in your report will contain available labels based on the layers you use. A note about the display of watershed labels needs to be considered when using the Print to File > Export function. The labels are based on the scale dependence range set for each watershed delineation provided. In other words the scale limits for the HUC 12 watersheds are between 100,000 and 250,000 while the HUC 14 watersheds are between 100,000 and all scales below. To be sure you have the correct delineation and label for your area, turn on the HUC layer and zoom in and out to see the changes in labels and decide which you need.

To be able to show a permanent separate layer of the boundary of your watershed only, you can add the zipped file created by L-THIA. The initial highlighting of the watershed or county will be replaced by the virtual display of any points clicked on the map when identifying data points. On the Map Legend, if you have a point selected when you export the map, the point will be shown as Override 1 on the exported image’s Legend. To make sure it is not in the Legend, be sure to check the box off under Map Layers. Scroll down the list; it is at the bottom and is called MyGraphicsLayer.

Next the IWQA has the capability to display the AIMS data when you click on a sampling point. This data is charted based on number of sampling events at any one site within the current AIMS dataset. There are dropdowns for the program type and for substances so you can chart each parameter from any of the programs for each of the sampling locations.

As you stop you cursor at any of the points along the chart, the exact value is given. A collection of these charts in a report can help illustrate parameters of interest for each or any specific site. Currently there is no download for the data, but copies of data in your area can be requested by contacting the IDEM Office of Water Quality (OWQ), Watershed Planning and Assessment Branch (WAPB) AIMS administrators and support staff. Also, you can request copies of the other IDEM data in tabular or geospatial format. Some of the additional data is also available for download and viewing in the IndianaMap interactive mapping application. If you have any difficulty finding what you need, feel free to contact your Watershed Specialist or the IDEM IWQA, GIS, or AIMS coordinators/administrators.

Lastly, the Print Map function provides for “print to file” in a choice of formats and page sizes. The page sizes are important when saving as a PDF; however it also helps to have the map layout scaled appropriately for the final presentation or report format you need to use to display your map. Once you save the file to your system or hard drive, you can print the file or insert it into another software application document (that would accept the image format you chose), and then print the document with your map included.