WMS Modules

The WMS interface is separated into several modules; these modules contain tools that allow manipulation and model creation from different data types.

Click on the modules list to the right for details of each component of WMS.

Map Module

The Map module provides a suite of tools for defining watershed data in a GIS and then using the information to directly create and manage hydrologic and hydraulic models, or as a support utility for data development with either TINs or DEMs. Results of watershed and floodplain delineations can also be saved in the map module and converted to GIS data layers for export.

Images are one of the four basic object types that are supported in the Map module. An image is typically a scanned map or aerial photo in TIFF or JPEG format. Images can be imported to WMS and displayed in the background to aid in the placement of objects as they are being constructed or simply to enhance a plot. Images can also be draped or “texture mapped” onto a TIN or 2D grid.

The Map Module supports the following image types:

TIFF JPEG

Land Use and Soil type layers can be created using feature objects in the Map module and then used to compute curve numbers or map other important modeling parameters. Other layers are also used for computing time of concentration or lag time, cutting cross-sections, mapping NFF regions, mapping rainfall and other parameters for the LA County modified rational (MODRAT) model, and streams for 2-D analysis using GSSHA.

A rough boundary and stream network can also be used to generate a TIN or two-dimensional finite difference grid that conforms precisely to streams and other important hydrologic features. Feature objects can also be used to create polygonal boundaries of soil type or land use to aid in the computation of curve numbers for hydrologic analysis.

Within the Map module there are several other tools which can be helpful in either setting up models or presentation of results to a client. Tools for reading and writing of CAD files (DXF and DWG) and part of the Map Module. Also included is a set of tools for adding simple graphics and annotation to a plot. These tools are not intended to be a full-featured drawing package as would be found in products like AutoCAD or Corel Draw. However, they can be very useful for adding titles, arrows, and other annotation to a plot so that the plot can be directly included in a project report without the need to import the plot into an external drawing package prior to report generation.

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GIS Module

Past versions have interfaced with GIS data primarily through shape files. Because WMS is not GIS software, management of these kinds of data (in particular land use and soils layers) has been limited. The capabilities to process large files, clip out regions of interest, or join soils database tables together to extract important information have not been available. WMS has undergone some major changes from previous versions in the way that GIS data can be read, displayed, and used for developing hydrologic modeling parameters. The tools for reading, displaying, and converting GIS data have been separated from the Map module to form a new GIS Module. The GIS module has two modes of operation:

1) If you have license of ArcView (ArcEdior, or ArcInfo as well) version 8.0 or higher then you can enable the use of ArcObjects within WMS. This essentially allows you to run ArcView within WMS and includes the capability to open any GIS data file that ArcView can open including images, ESRI formatted coverages, CAD files, new geodatabases, and shape files. ArcObjects functions also allow the control of display, table viewing and joining, and many other ArcView capabilities within WMS.

2) If you do not have a license of ArcView 8.0 or higher then the GIS module will allow you to read in and display shape files as GIS layers. Only a portion of the capability for displaying data, tables, and other GIS functions are available with shape files, but unlike previous versions of WMS large shape files are more efficiently read and displayed as initially the shape file is not converted to a WMS coverage.

A key feature of the new GIS module is that individual features (points, lines, polygons) can be selected from the GIS layer and then only the selected features are converted to feature objects in WMS coverages. This allows you to read in a large soils data layer, select the soils that cover your watershed, and only convert these soils to the WMS coverage.

Previous versions required this kind of manipulation to be done with ArcView or some other GIS tools, but now your GIS data can be managed completely using the tools in WMS. If you own a license of ArcView then you will have additional access to file formats and other advanced display capabilities.

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Terrain Data Module

WMS has a Terrain Data module where you create, edit, and preprocess all of your digital terrain data, whether it is a TIN or DEM. The Drainage Module then is used to delineate a watershed from either a TIN or a DEM. The terrain data in WMS can be contoured, displayed in oblique view with mapped images and hidden surfaces removed, and several other display options that can be set to visualize and understand the terrain surface better.

At first glance you may wonder if we mixed and matched the TIN and DEM tools in WMS. However, there are good reasons why we have done this. We have several tools that allow you to edit elevations and process both TINs and DEMs to process them not only for watershed delineation, but also for hydraulic modeling using our HEC-RAS interface tools. Some of the powerful tools now available in the Terrain Data Module include:

The ability to edit DEM elevations. You can now define a feature arc and then in a DEM elevation-editing environment adjust the elevations. This could be used to “carve” out a canal or other small stream not accurately represented by the original elevations of a DEM. You could also insert a highway embankment or other such structure that may act as a levee and alter watershed or flood delineation Much faster and more robust TIN triangulation and processing Tools to thin LIDAR and other dense triangulation sets are provided Tools to extract the significant elevation points from DEMs have been implemented Contours from TINs or DEMs can be exported as feature lines (then to shape files for sharing in a GIS) Options to merge data from a TIN and a DEM together to create a composite elevation data set Tools to quickly convert a DEM to a TIN and vice versa

A major feature of the Terrain Data Module is the option to generate flood depth and extent maps based on the digital terrain model and water surface data. WMS contains the most complete and powerful floodplain delineation options available. Some of these are: lateral interpolation of W.S.E. along cross sections, stream center-line interpolation of W.S.E. between cross-sections, fully 2D interpolation of flood depths over the surface of the terrain, flood barrier inclusion (buildings, levees, walls, etc.) without tedious terrain editing, flow path/distance restiction options. Contouring and 3D rendering of flood maps is also part of the Terrain Data Module.

Since much of the power of WMS is dependant on using digital terrain data, WMS can import/export several formats of digital terrain data including:

USGS DEM files (all formats) ARC/INFO ASCII Grid files USGS NED files GRASS grid files DTED grid files Scatter survey points (XYZ text format) Polyline contours from GIS or CAD TINs from CAD software (DXF or DWG)

Information on terrain data types and acquisition of such data can be found at the following URL. The WMS developers and users have created a website for reference on geospatial data acquisition, along with examples, step-by-step instructions, and user tips.

WMS GeoSpatial Data Aquisition – http://emrl.byu.edu/gsda/

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Drainage Module

The Drainage Module in WMS allows you to automatically delineate streams and watershed/sub-basin boundaries based on the land surface represented by the DEM or a TIN. One of the best features of WMS is the flexibility and control you have when using the automated delineation method. You can use any stream network (automatically generated or manually digitized) in conjunction with a land surface to delineate drainage areas. You can also manipulate watershed boundaries generated by WMS or create them entirely on your own and let WMS match the terrain data with the watershed delineation you know is correct.

A complete watershed model can be constructed using the Drainage Module. Basin characteristics and routing parameters such as slopes, distances, flow paths, etc. are automatically determined as part of the delineation process. The option to automatically create storage features (reservoirs/detention ponds) is also included. WMS will compute elevation-volume-discharge curves based on the land surface and streams of your watershed model. All parameters computed during delineation are set up for input to any of the models supported by WMS – the software places the appropriate parameter for each possible model in the input fields so you can confirm/review the data easily.

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Hydrologic Modeling Module

The Hydrologic Modeling Module, sometimes referred to as the Tree Module, is the center for hydrologic modeling input, execution and output review. Each hydrologic model supported by WMS has a complete graphical interface in this module (HEC-1, HEC-HMS, TR-20, TR-55, NFF, Rational Method, HSPF, MODRAT, OC Rational, xpswmm, and EPA-SWMM). The model interfaces allow you to view and edit model input parameters quickly and easily. The watershed models built using the Map or Drainage Modules are linked to a simple schematic (tree) representation in the Hydrologic Modeling Module. This allows you to quickly select and edit basin parameters and stream (reach) parameters.

WMS reads and writes native model files (such as HEC-1 files) from this module. WMS allows you to use model files created in other systems or by hand by reading in the modeling information and building a schematic representation (tree) for you to use as you update or review the model. You can save any model back to a native file format – including the new HEC-HMS format.

The Hydrologic Modeling Module also contains the tools for computing complex hydrologic parameters (using your digital terrain or GIS data) needed for input to a model. This functionality includes:

Once a model has been completed, tools in this module allow you to open flow results (peak flow reports, hydrographs, etc.) and plot them with your model. You can also export model results to more useful formats (spreadsheets, tables. etc.) from this module. Anyone who has tried to sort through a complex model output file will appreciate this functionality.

Finally, the Hydrologic Modeling Module contains several “Calculator” tools for calculating modeling input or analyzing model output. These include:

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River Modeling Module

The primary purpose of the hydraulic modeling interface within WMS is to process digital terrain and map data (TINs and coverages) to build the basic geometry necessary for a 1D Hydraulic Model. WMS supports HEC-RAS, SMPDBK, xpswmm, and EPA-SWMM in the river module. See the WMS Models section of this page for more information on each hydraulic model.

When creating a 1D hydraulic model, WMS will help you do the following:

Creating/editing stream center lines, bank lines, and cross sections Assigning roughness values to line properties on the cross sections automatically from map data such as land use Extracting cross sections from the TIN and initializing the 1D Model with the cross section and connectivity data Export the GIS data and finish defining HEC-RAS (or other model) Importing HEC-RAS results for creation of floodplain maps Importing SMPDBK results for predicting downstream flooding Creating/editing storm drain pipe networks and assigning parameters to pipes Writing and reading xpswmm and EPA-SWMM files and bringing these files into their respective applications directly from WMS

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Scatter Point Module

The 2D Scatter Point module is used to interpolate data from scattered points to grids or TINs. WMS supports several interpolation schemes including linear, natural neighbor, inverse distance weighted, and Clough-Tocher.

Interpolation from 2D scattered data is used primarily for floodplain delineation in WMS. Flood stages can be input anywhere using a 2D scattered data set; WMS then uses interpolation to “fill” the floodplain and compute extents and depths.

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2D Grid Module

The 2D Grid module is used for surface visualization and for the development of distributed (2D) rainfall/runoff analytical models. For example, the user can discretize a watershed into a number of grid cells and then define important rainfall, infiltration, and channel properties at grid cells in preparation for running a 2D distributed model such as GSSHA or a quasi-distributed model such as MODClark. Any parameter such as hydraulic conductivity or rainfall intensity may be interpolated from a set of scattered data points to the grid. Results of the 2D analysis can then be contoured on the grid or displayed with hidden surface removal and color fringes to display the variation in the computed results.

After running a distributed model such as GSSHA, the time-varying output can be exported to Google Earth as a KMZ animation file and the animation can be viewed in Google Earth.

WMS includes several tools for the creation and editing of 2D finite-difference grids in the 2D grid module. Grids can be automatically generated using the Map and Terrain Data Modules or they can be created based on options set by the user in the 2D Grid module.