New Version of MODFLOW-NWT (1.0.5)

USGS released a new version of MODFLOW NWT (1.0.5) on May 14.  We have it in Groundwater Vistas Version 6.20 Build 4 on our web site now.  Several changes were made to the code including some changes to the meaning of the keywords "simple", "moderate", and "complex" in the NWT solver.  An option was added to output data for wells where pumping rates were reduced.  This is not yet supported in Vistas. Bugs were fixed in SFR2 and MNW2.  Some of the output formatting was also changed for these 2 packages. 

Error checking is now added for the Drain, GHB, and River packages.  If the head assigned to either of these packages is below the layer bottom, an error is reported and the model stops.  So if you have a model that ran fine before this update and now it stops, that is likely the reason.

Finally MNW2 fluxes have now been added to the Link-MT3DMS file.  Actually we had added this a while ago but it is now official in the USGS release.

One other change has been made related to LAK3 Package.  There was a bug in MODFLOW2000/2005/NWT for 2D models that include lakes.  Actually it's possible that 2d models were never supported with LAK3 - not sure about this.  In any case, this problem causes the model to crash.  I reported this to USGS and they fixed it very quickly.  It is not in their release yet but they were kind enough to send me the fix.  So our versions of MODFLOW2000, 2005, and NWT all have this change.