Is there any way to generate a stream network (vector file) from within GRASS based on a DEM? --j -- Jonathan A. Greenberg, PhD NRC Research Associate NASA Ames Research Center MS 242-4 Moffett Field, CA 94035-1000 Office: 650-604-5896 Cell: 415-794-5043 AIM: jgrn3007 MSN: jgrn3007 at hotmail.com