[GRASSLIST:1365] GRASS integration with MODFLOW

[Rick Gagne]

I am starting up a large urban land use groundwater quality study (40 km by 60 km 
study area, 50 m cell size, 3000 wells to be sampled 10 times over 15 years) in 
Nova Scotia, Canada, for which GRASS is beautifully suited.

GIS information will include: geology (soil and bedrock lithology, chemistry, 
metamorphic grade, mine locations, known mineral deposits, depositional and 
structural fabric), physical hydrogeology (site well construction and geology data, 
average pumping rates, groundwater elevation, seasonal level changes), lake 
water chemistry, topography, precipitation and other climatic data, vegetation, 
groundwater recharge characteristics (derived from other layers), prevailing wind 
direction (study sea spray affects), all available urban land use data, any other 
information useful to the study, plus 40 to 50 chemical parameters (and various 
interpretation maps derived thereafter).

I will also need to do 3-D groundwater modeling in the study area (perhaps at 
various scales), and I am thinking of using MODFLOW and other related USGS 
groundwater modeling programs for that purpose. In that regard, the only Linux 
pre-post processor for MODFLOW that I am aware of is Uncert (are there 
others?), which I have not tried yet. However, it would be great if I could integrate 
GRASS with MODFLOW somehow to facilitate the study.

I understand that someone did some work to integrate MODFLOW with GRASS 
(version 3.0?). Does anybody know what may have come of this work? Has 
anyone tried to integrate groundwater models (MODFLOW in particular) with 
GRASS versions 4 or 5?  Finally (a concept question for those with knowledge of 
the GRASS inner workings and direction of development), would it be difficult to 
write code to integrate MODFLOW, MODPATH and perhaps other related USGS 
groundwater migration model programs with some future version of GRASS?

Regards,

        Rick

RG Hydro-Environmental Ltd.
WaterWatch ..... independent groundwater research

Richard Gagne, P.Geo., President
PO Box 25099
Halifax, NS  Canada   B3M 4H4

e-mail: rghydro at waterwatch.com
phone: (902) 457-7010
fax: (902) 457-3934