MODFLOW-NWT Documentation Released
MODFLOW-NWT handles dry cells in a manner similar to MODFLOW-Surfact's pseudo soil relations. So if you do not want to spend the money for MODFLOW-Surfact, then MODFLOW-NWT is a viable alternative. The downside is that MODFLOW-NWT can be slower than MODFLOW-Surfact. I have confirmed this with some test problems and real models. But it works!
The source code should be available in a few days. As soon as the source code appears on the USGS web site we will activate this feature in Groundwater Vistas Version 6. I will make another post when that happens.
Link to MODFLOW-NWT manual: http://pubs.usgs.gov/tm/tm6a37/