Latest Contributions by MarkBoucher

I just replied to a similar question at DEM Reconditioning: Err Msg "Object ref not set to an instance of an object." . ... View more

Make sure the geoprocessing extents include your whole project area. It seems the software will reset them to a wrong limit w/o me knowing about it and then I get confusing results. You can reset them under Geoprocessing>Environments. I use the DEM limits when I reset them. It could also be a projection issue with your data so make sure the projections are all the same. Last idea is that the process bombs for some reason and only processes part of the data. You'd think you would get an error message if this happened. A guess would be that the raster has some "null" value and the tool can't handle. In that case you could use the CON() function to make sure that there are not grids in the DEM that are null. This is a wild guess. Please post the solution if you find one! ... View more

I've learned that this error basically means there is a "null" value in some data that the tools are trying to use. Maybe there is a hiccup in the data transfer over your network, or a key variable or data field is "null", or missing... something like that. I've posted several tips on how errors can be avoided in Arc Hydro. These are on a thread named "Arc Hydro Problem Solvers" (ArcHydro Problem Solvers). Some basic things to try that are probably posted on that thread: Put your data on your local drive (working over the network is slow and also induces errors for some reason). Put your agreestream and other base layers (innerwalls, outerwalls) in a geodatabase (for some reason many errors went away when I started doing this). Make sure your Target Locations are correct. If you renamed the data frame or the mxd but did not reset the Target Locations, you might get an error like this. Hope you find and post your solution. ... View more

Regarding the smooth and sharp drop/raise values: The Arc Hydro help explains the three input. Here's my interpretation and practice (bullet items): Stream buffer (cells) – this is the number of cells around the linear feature class for which the smoothing will occur. I've found that the narrower this is, the less it disrupts what the rawdem "tells you" about the surface. I usually use 2 and I work with a 10' DEM. I believe you can use 1 and still have it work. Smooth drop/raise – this is the amount (in vertical units) that the river will be dropped (if the number is positive) or the fence extruded (if the number is negative). This value will be used to interpolate DEM into the buffered area (between the boundary of the buffer and the dropped/raised vector feature). If you don't want to wipe out levees around your stream, then keep this low. If after you look at your flow direction (fdr) grid and you find that the fdr creates parallel streams where there should be only one, then increase this. I understand (I think correctly) that this basically smooths out the banks of your burned in stream so that any parallel streams or any pockets that should flow directly to the stream, but wouldn't otherwise, are eliminated. You can use the flow path tracing tool in the Arc Hydro toolbar to investigate. If you get parallel streams, you will want  more smooth drop. So, to see what smooth drop/raise you need. Start with zero and just go to the flow direction grid in the processing and stop. Then see if you have any flow direction issues right along the streams that you don't want, increase it. Sharp drop/raise – this is the additional amount (in vertical units) that the river will be dropped (if the number is positive) or the fence extruded (if the number is negative). This has the effect of additional burning/fencing on top of the smooth buffer interpolation. It needs to be performed to ensure preserving the linear features used for burning/fencing. This value can be very large (10,000 would even work). Where the agreestream polylines are, the burning process lowers those cells this depth. I've never used this to extrude a "fence". I use innerwalls for that. Since the ultimate goal is to get a good flow direction grid (fdr), the final elevations of the agreedem or walleddem (if you build walls too) are not that important. All of the rest of the processing is dependant on the fdr. If you need an elevation later you will take that from the rawdem. Hope this makes sense and is helpful. ... View more

So it seems there is a 10.2 problem. Sorry, I haven't had 10.2 to play with. I have noticed that ESRI has a 10.2 version of Arc Hydro. Have you installed that? I found links to it. You can search the forums for "Arc Hydro Setup Versions" or go to this link: (https://community.esri.com/message/393615#393615‌). Based on that thread, ESRI will continue to post the downloads on the mft site at (https://mft.esri.com/EFTClient/Account/Login.htm‌). This thread has the login and password info (https://community.esri.com/message/91152#91152‌). There might be a better way to direct you to other threads. I was off for 4 weeks and came back to the new geonet format. Still adjusting. ... View more

The agree stream layer I use is the storm drain layer that helps define the flow pattern in flat urbanized areas. It also includes “streams” I use to cut through rural road embankments and freeway embankments where there are culverts. ... View more

Glad it is working! I have my agreestream layer in a gdb. I've been using 10.1. We haven't "upgraded" to 10.2 yet. I stopped changing the layer names in the tools a while back and started just using the layer names the same as the Arc Hydro defaults. So, I use "rawdem", "agreestream", "innerwalls", etc. Succumming to the defaults saves time for me because each project actually references the same agreestream and walls layers. I work in and for the county and so it make sense to build on this layer over time. If I have adjacent watersheds of datasets to bring into the agreestream layer, I don't have to clip them. I believe the processing extents limits where the tools "look" and it doesn't add much to the processing time. At least I don't have to take the time to clip them for every project. When I move the data to the C:drive, this actually only has to include the rawdem and the mxd. My agreestream and walls layers are actually left in a gdb on the server. The creation/read/write of the rasters that precipitate from the process are the ones that I believe are better to have (or have created) on the local drive to eliminate the HRESULT E_FAILerror. ... View more

Layla - Have you tried moving your data and project to your local PC hard drive? I don't see that in that on your list of things you've tried. Make sure your folder path is short and simple with no spaces (I used C:\GIS\MoragaPt25 for my last one). Put the agreestream layer in a geodataset. I found that seems to work best. Start a new mxd and add base layers to is. Mine are rawdem, agreestream, innerwalls, outerwalls (only use outerwalls once in a while). By starting a new mxd, the target locations get set automatically. Let us know if you done this, and if not, if when you do it, if it helps. ... View more

Nice to know that it does remember. I'll have to confirm that for myself next time I have to use it. I just recall wanting that functionality for the topology tools and not seeming to be able to get it; that is, it seemed like whenever I re-validated that it would re-highlight those that I had marked as exceptions. ... View more

I don't think Arc Map remembers the exceptions.  It has been a while, but my recollection is if you validate again, the previous exceptions are lost and you have to redo the exceptions. A little frustrating. ... View more

This is how I would have done it, using additional data frames inserted over the base map. The maps look like they are for a utility. The insets are blowups to show more detail where the basemap scale does not allow the that much detail. If the data sets in the inset data frames are the same as that of the main data frame, you can copy the basemap data frame, paste it, and then resize and reposition it and make sure it is in front of the basemap. ... View more

Did you fill sinks? Failing to fill sinks can result in gaps like this. ... View more

Geoprocessing over a network can cause errors for some reason. Try putting a copy of your destination.shp data on your C: drive an see if that doesn't fix it. Also, working with geodatabases instead of shape files is more stable, so if the first suggestion doesn't work, try putting the data in a geodatabase. ... View more

See tips at http://forums.arcgis.com/threads/48100-ArcHydro-Problem-Solvers?p=270146&viewfull=1#post270146. ... View more