flooded area

[Frank Lederer]

hello GRASSers,

I want to determine the temporary flooded area of a river (meadow). Based on
a streamchannel layer generated by r.watershed from a DEM I want to seperate
regions, whose elevations are a defined ammount higher than the raster cells
of the streamchannel layer. 
Is it principal possible to do this with r.mapcalc or is there a more simple
way to solve my problem...

thanks for enlightenment
                        Frank
 _____________________________________________________
 \                                                    \
  \ Frank Lederer          phone: ++49-069-4960545     \      
   \ Sandweg 64             Lederer at em.uni-frankfurt.de \     
    \ D-60316 Frankfurt/Main                             \     
     \____________________________________________________\