Aquaveo & Water Resources Engineering News

When working with the Watershed Modeling System (WMS) and the MODRAT model, one potential aspect of your watershed analysis would be determining the percent impervious values for each sub-basin. Accurate percent impervious calculations may significantly influence your hydrologic modeling outcomes. Here is a guide to help you navigate this process effectively.

Importing Land Use Data

To compute the percent impervious for each sub-basin in MODRAT, you need to start with accurate land use data. Land use data in WMS is typically stored in the GIS and Map modules. The most efficient way to read this data into WMS is through a shapefile. Here’s how you can do it:

1. Create a Land Use Coverage: In WMS, start by creating a new land use map coverage. This coverage will hold all the land use data you import.
2. Import the Polygon File: Import your land use polygon shapefile into WMS. This file should contain various land use types and their respective boundaries.
3. Assign the Percent Impervious Field: Ensure that the percent impervious field, often labeled as IMPERV_ by the Los Angeles County Department of Public Works (LACDPW), is correctly mapped to the LA County Soil land use field in WMS. This step is crucial as it links the impervious data to your land use coverage.
4. Compute and Assign Percent Impervious: With the land use data now present in WMS, use the "Map Attributes" command in the MODRAT menu to compute and assign the percent impervious values. This function will analyze the land use data and calculate the percent impervious for each sub-basin.

Using Coverage Overlay Options

Another method to determine the percent impervious values is by using the Coverage Overlay options in WMS. This approach is similar to calculating curve numbers and involves overlaying land use coverage with drainage coverage.

1. Overlay Land Use and Drainage Coverage: Start by overlaying your land use coverage with an existing drainage coverage. This will combine the datasets, allowing for an analysis of land use types within each drainage area.
2. Calculate Percentages: The overlay will provide you with the percentages of different land use types within each sub-basin.

Whether you choose to import land use data directly or use the coverage overlay options, both methods can aid in determining the percent impervious. Use either method in your MODRAT projects in WMS today!

Do you have to refine the recharge options in your MODFLOW-USG Transport model in the Groundwater Modeling System (GMS)? With GMS 10.8, we’ve added two options to the MODFLOW-USG Transport Recharge Package. Concentrations (CONC) option and Use Seep Elevation (SEEPELEV) option have now been added as options to the main dialog. This makes it easier to add the data required when concentrations and/or seepage elevations are required for certain species. These additions can improve the accuracy and applicability of groundwater models, particularly in complex and variable hydrological settings.

Adding the Concentrations (CONC) feature to the Recharge (RCH) package in MODFLOW-USG Transport allows you to account for the spatial and temporal variations in the concentration of contaminants or solutes in recharge water.

The Use Seep Elevation (SEEPELEV) feature enables you to consider the elevation of seepage faces in your simulations. This is particularly important in areas with complex topography and variable groundwater-surface water interactions.

In order to use these options:

1. Go to MODFLOW | Global Options.
2. In MODFLOW Global/Basic Package, select Packages.
3. Make sure “RCH1” has been selected as one of the packages.
4. Then, access the RCH package options using the RCH - Recharge Package command in MODFLOW | Optional Packages menu. You can also reach the options by double-clicking on the RCH package in the Project Explorer.
5. In the MODFLOW Recharge Package dialog, look for “Concentrations (CONC)” and “Use Seep Elevation (SEEPELEV)”. They will appear below the “Recharge option (NRCHOP)” drop down.
6. Select one or both of them, depending on your model’s needs.
7. For the seep elevation, you can manually enter or import the appropriate data.

Note: These options are only a part of USG Transport and are not available in other versions of MODFLOW..

With these two options now available in MODFLOW-USG Transport, better refinement in your groundwater models is now possible. Head on over to GMS 10.8 to try out the Concentrations (CONC) and Use Seep Elevation (SEEPELEV) options in your MODFLOW-USG Transport projects today!

Jumping between multiple projects can be commonplace in most organizations. For this reason, the Surface-water Modeling System (SMS) includes a way to see your most recent projects. This feature makes it easier to jump between projects.

When starting SMS, you can see your recent projects by going to the File menu. Towards the bottom of the File menu, you will see the five most recent projects. Selecting any of these projects will load them into SMS.

Only the five most recent projects are listed in the File menu, but SMS provides a way to access more of your recent projects. Clicking the More… command under the recent files in the File menu will bring up the Recent Files dialog. The Recent Files dialog contains a list of recent projects. This list will go back to when the major version of the software was installed.

The Recent Files dialog allows you to search for past projects using the Search field at the top of the dialog. This can be immensely helpful when trying to find a project that has been neglected for a while.

Also helpful is a feature that lets you open the location of the project files. You can right-click on any project and select the Open Containing Folder command to bring up the folder containing the project files in the File Explorer window. This can help you locate files you haven’t been working with in a while and may have forgotten the location.

There are some caveats to this feature. If the project files have been moved, the project will still appear in the list of recent files but SMS will not be capable of importing the file because it is being directed to the wrong location. This is also true if a folder in the directory is renamed.

The Recent Files dialog provides a great tool to help you manage your projects in SMS. Head over to SMS and see what projects you have been working on recently!

When working in the Watershed Modeling System (WMS) the software refers to multiple applications and files in order to operate correctly. The default settings for accessing these files should generally be followed. However, there are times when these file paths need to be altered by you or the paths get changed unintentionally. This post will go over some of the important file paths to pay attention to in WMS.

Typically, WMS will be installed on your C drive or whichever drive you specify on your local machine. When WMS is installed, it will also install multiple other applications that it uses. These are most often the numerical models that WMS uses along with some drivers. WMS will keep everything contained to where it can find these applications.

However, to give you more flexibility, WMS allows you to change the location of these applications. Most path locations can be changed in the Preferences dialog. The Files tab of the Preferences dialog contains the file paths for the numerical models and other applications. The file paths can be changed here to direct to a different location. This can be useful when you are needing to use a different version of a model executable other than the one that comes installed with your version of WMS.

The Preferences dialog also allows you to change the file path for the Temp directory. This is done on the General tab.

It should be noted that WMS retains these file paths once they have been set. Therefore, when you are moving files around, pay attention that WMS will not automatically update to the new location. When a model executable gets moved to another directory, you will need to manually update the file path in WMS in order to avoid potential errors.

The Files tab of the Preferences dialog is also useful for locating specific model executables and files that you suspect may need to be updated. This can help you troubleshoot model executable issues that occur during a model run.

Now that you know more about how WMS manages file paths, make use of them in your WMS projects today!