Hi Scott, it looks like that end curve is not smooth - it has sharp corners in it in those areas that then leave the features you don't want.

Network will generate a smooth surface only across smooth curves. If any curves have any sharp corners in them those areas basically form separate strips in the network.

So you'll want to get that last curve to be all one smooth curve in order to avoid that - rebuild is one easy way to do that, run rebuild set it to the "# of points" option, with "Keep corners" turned off, and use something like 30 points or so. That should make a smooth curve at that spot and that will then avoid the "stripification" of the network that you're seeing.

- Michael