We have ArcView 10.0 and Spatial Analyst. Would the flow direction and basin tools within Spatial Analyst's Hyrdrology Toolset be appropriate for defining a capture zone in a groundwater collection system?
Simple answer is yes you can do it with just Spatial Analyst Hydrology toolset, but you'd find the free ArcHydro Tools extension easier for processing your DEM.
You'll likely be generating a watershed feature as drainage area for input to your water equations, so you just need one small component of what ArcHydro can do.
Either way you'll need some documentation of the concepts and processing steps. You can use the ArcGIS Desktop help articles (start here). But the help files delivered with ArcHydro Tools are probably the best reference for the processing you'll need to do. Unlike the ArcGIS Desktop Help, the ArcHydro Tools help is not online so you'd have to install the extension.
So you'd need to install the current ArcHydro v 2.1.0.152 from the ftp site. Then either activate Spatial Analyst and the ArcHydro toolbar and closely read the Help. Or, once installed, the ArcHydro compiled HTML help can be read off line. The file is ARCHYDRO.chm located in the C:\Program Files (x86)\Esri\WaterUtils\ArcHydro\bin folder.
Read up, and post back if you need help with the processing sequence for your DEM either with Spatial Analyst or via ArcHydro Tools.
