Hi, I have a few questions about using the hydrology toolset in ArcGIS.
After creating the Flow Direction model, I identified the sinks and found that there were some reservoirs which were not included as sinks. I assume that this is because the DEM did not capture the elevation profile for these areas properly. I have a polygon layer of the reservoirs, but unfortunately with no depth profile. Will this help?
When I eye-balled through the sinks, I realised that a lot of them has the value of "No Data". How do I fill up these sinks for such instances to separate them from the true positives?
if the reservoirs are nodata, then you will have to assign them a reasonable elevation appropriate with the surrounding terrain. This can be accomplished with a combination of IsNull and Con as described in the link. Obviously a value of 1 meter would pretty well make it a deep sink in most parts of the world.
