[GRASS-user] analysing regional hydrology potential

[Tim Michelsen]

Hello,
I would like to use GRASS for analysis regional potential for hydrology 
applications like run-off / small scale hydro power.

So from a DEM I would create watersheds. But then I am still unaware of 
which tools and methodology to use.

Is there a article or publication that detailes on such work?

Like getting from a DEM with some information on precipitation and water 
levels of rivers to a estimation of regional river run-off quantities?

Looking forward to your pointers.

Thanks in advance,
Timmie