Aquaveo & Water Resources Engineering News

GMS Webinar July 21, 2011

The GMS team held its first webinar on July 21, 2011. The webinar highlighted new features in GMS 8.0 and 8.1. We wanted to thank everyone that took time out of their schedule to attend the webinar. If you have any feedback please send it to us at
We hope to post a recording of the webinar shortly. Here is a list of some of the features that were demonstrated:

  1. General Features
    1. Learning Center -
    2. YouTube channel -
    3. GMS Community Edition -
    4. Import from Web
    5. ArcGIS map server layers
  2. Improved 3D Graphics
    1. Transparency
    2. New lighting options
    3. Faster data set switching
    4. Faster frame rate (real time pan/rotate)
    5. Block Fill contours
    6. Save to Google Earth
  3. New Modeling Features
    1. MODFLOW 2005
    2. UZF Package
    3. LMG3 package - Parallel Versions of MODFLOW 2000 & 2005
    4. Open Containing Folder
    5. Parameter Estimation - Different types of regularization
    6. SEAWAT
    7. Regional to Local model enhancements
  4. 64 bit Version of GMS
    1. Coming with version 8.1
    2. Load larger models
    3. Work with larger data sets
    4. 64 bit versions of MODFLOW

June 2011 Sprint Highlights

Some of the more interesting accomplishments from the June 2011 sprint:
  • Fixed over 37 bugs
  • Got "Learn GMS" help menu command working for 32 and 64bit
  • Fixed issues with 64bit and small allocations
  • Found and fixed several memory leaks
  • Added units tests for all the projection and reprojection stuff
  • Almost completed the 3D grid display option to contour a second specified data set
  • Tested and debugged 64bit version with a large MODFLOW model
  • Fixed order of Annotations tool bar and fixed north arrows to open installed north arrows folder by default
  • Cleaned up the wiki and made good progress on the Wiki to PDF feature
  • Added some unit tests for kriging and fixed some kriging bugs
  • Fixed slow drawing of rasters
  • Attended the MODFLOW & More conference in Golden, Colorado
  • Completed designs for MODFLOW-NWT and MODFLOW-MNW2
  • Added a new video to the YouTube channel about the free GMS Community edition

May 2011 Sprint Highlights

Some of the more interesting accomplishments from the May 2011 sprint:

  • Added three new GMS videos on the YouTube channel.
  • Fixed 24 bugs
  • Created an installer for GMS 8.1 for 32 and 64 bit
  • Created 64 bit versions of MODFLOW
  • Got 64 bit tests of MODFLOW running
  • Added a preference for 64 bit MODFLOW
  • Made good progress on restoring ability to contour and block fill at the same time
  • Finished fixing the annotation bugs to be included in 8.1
  • Created a local help page, similar to the online learning center, which will direct users to the tutorials installed locally
  • Created a table of contents for the wiki and got PDF generation of the wiki working. A locally installed PDF version of the wiki will be available with GMS 8.2.
  • Added code to MT3D model checker to look for missing species in the conceptual model
  • Almost finished basic raster implementation (raster objects coming in GMS 8.2)
  • Wrote a design for MODFLOW-NWT
  • Changed some MODFLOW dialogs to conform to the standard for variable names
  • Made lighting dialog display changes instantly in graphics window

GMS Resources for Educators

We recently created the GMS Resources for Educators page at There you can find sample lectures, in-class exercises, and homework assignments for a one semester, college level course in groundwater modeling. The course teaches groundwater modeling principles with an emphasis on MODFLOW and MODPATH. GMS is used as one of the software tools in the course and a lot of time is spent building real models on the computer. From the course description, "This course is application oriented. We cover the fundamental equations and the modeling theory but the emphasis is on teaching you how to solve real world problems. At the end of the semester, you should feel confident in your ability to develop and calibrate a complex 3D groundwater model."

Dr. Norman L. Jones has taught this class for years at Brigham Young University as CE 547 - Groundwater Modeling. He continually updates and improves the material. To obtain the entire curriculum with a syllabus, tests, and answers to the homework assignments and the tests, email Dr. Jones

At the end of the course students complete a case study of the Woburn site described in the book A Civil Action. If you are familiar with the book or the case, you might be interested in the excellent Woburn Hydrogeology Data page maintained by Dr. Jones which includes all sorts of raw data for use in building a groundwater model, as well as photos of the area and even photos of many of the key players in the book. The case study is designed to be done with the students divided up into small teams - some teams working for the prosecution, and some for the defense.

MODFLOW and More 2011

Members of the GMS team recently attended the MODFLOW and MORE 2011 conference in Golden, Colorado. The conference was great. There were many presentations related to MODFLOW modeling and groundwater in general. One interesting development was the announcement of MODFLOW USG (Unstructured Grid). This version of MODFLOW is not yet released but it looks quite different from current versions of MODFLOW.

It was good to meet current GMS users and get feedback on improvements that can be made to GMS. Thanks to all those that came by our booth.

Contouring and block fill improvements

In GMS 8.0, the contour options were updated and improved. Most of the changes were behind the scenes in code that results in faster contouring which uses less memory and is more accurate. But the interface changed too. The old and new dialogs are shown below. The new dialog is cleaner and easier on the eyes. It also includes a new option - Block fill - for the Contour method. This option only applies to cell-centered grids and results in cells filled with a single color based on the value at the cell center. Block fill was previously only available for 3D grids as a separate display option and limited range and color ramp options. Now block fill is available for 2D and 3D grids and, because it's part of the Contour Options, the full suite of range and color ramp options are available.

Unfortunately by merging the block fill option in with the Contour Options we lost the ability to do both at the same time - that is block fill one data set and contour another data set. But the soon to be released GMS 8.1 restores the ability to do both at the same time.

Old Contour Options dialog.

New Contour Options dialog.

April 2011 Sprint Highlights

Some of the more interesting accomplishments from the April 2011 sprint:
  • Fixed 22 bugs.
  • Created 64 bit versions of MODFLOW.
  • Taught the GMS training course in Dresden, Germany.
  • Updated the tutorial docs and files on the wiki for GMS 8.0.
  • Fixed some issues with the IUZBND array in the UZF package.
  • Documented MODFLOW world files on the wiki.
  • Simplified code behind Contour Options and Raster Options dialogs.
  • Added tests for the Set Arc Directions From Stream Data feature.
  • Researched converting the wiki to a pdf or chm file.
  • Fixed some coding problems that were resulting in compiler warning.
  • Changed the Visual Studio project for 64 bit GMS to follow pattern of 32 bit property sheet.
  • Added to the suite of 64 bit test.

GMS Learning Center and YouTube channel

In order to help make it easier to learn how to use GMS, or to just see what GMS can do, we recently launched the GMS Learning Center at  All the GMS videos we've created so far are available there. These are YouTube videos so you can also find them all on our Aquaveo channel on YouTube. Look for the GMS playlist. These videos are all recorded in high-def so they're best watched full screen at 720p. We add a few new videos each month. Various folks around the office have been recruited for the voice recordings and none of them are professional voice actors but we think they've done a pretty good job.

Also at the GMS Learning Center are all the standard tutorials which ship with GMS. The tutorials can be freely downloaded and completed offline. Finally there are links to the wiki, the user forums, the training courses, and a new Resources for Educators page that will probably warrant it's own blog post in the near future.

Better MODFLOW observation plots

GMS has included observation tools for a long time. These work with any numerical model and let you compare field observed data with model computed output. With transient data, the time of the observations doesn't necessarily match the model output times. In this case GMS would do a temporal interpolation to come up with a model calculated value.

When MODFLOW 2000 came out it included built in observations calculated when you ran MODFLOW. Now if the observation time didn't match the output time it didn't matter because MODFLOW would be sure to calculate an additional output at the observation time.

The residual errors calculated by MODFLOW have been available in GMS since shortly after MODFLOW started computing them but the GMS observation plots still behaved the old way, by doing a temporal interpolation. Until now. We just replaced the old way with the new and revamped several observation plots. The following images illustrate the difference.

Old and busted. Notice the interpolation times of the upper and lower range don't always match the observation times.
New hotness. Upper and lower bands replaced with fixed point-in-time box symbols. The color makes it easier to interpret.


GMS 8 has an interface to the USGS SEAWAT model. SEAWAT is a combination of MODFLOW and MT3D that allows for the simulation of density dependent flow and transport. I have included an animation of one of the sample problems from the SEAWAT documentation. We also have created a tutorial that shows how to use the SEAWAT interface within GMS.