Hydrology Help

Discussion created by trisandhi on Dec 9, 2013
Latest reply on Dec 10, 2013 by curtvprice

I am trying to find  a way to find the upslope contributing areas  to  various pour points within one watershed to determine the land use percentage contributions to correlate to  water quality data collected at these pour points. I created a DEM from contours and followed the procedure of filling the DEM, creating a flow direction raster, a flow accumulation raster, imported my pour point data set which are water quality monitoring sites along the streams. I also used the snap pour point tool to connect them to the flow accumulation raster. But when I run the watershed tool it only returns a couple tiny contributing areas and the rest of the watershed is blank. I've read that if the pour points do not lie on the high flow accumulation path these errors occur and the snap pour point tool should be utilised but it doesn't seem to respond regardless of the threshold size.  Are there any other suggestions that I can use to determine what I am trying to find? Any help would be greatly appreciated.