Hi Michael, this is import cleanup. These type of changes have been discussed more than once on the mailing lists, and there are diary posts like @bdiscoe/diary/37473 and @bdiscoe/diary/37421 which clarify the matter. I am happy to be more verbose than "clean up Canvec waterways" in my changeset comment if you like; would you prefer a longer phrase, or including the 80cm setting?

Hi, thanks for the information. I'm glad you remember the changeset since it was only 5 hours ago :-) It sounds like you do know what you are doing. That "Digitalglobe EV" must just happen to match Bing. BTW, what does #akros mean? It would be good to put more in your changeset comments to explain what is being uploaded (like, mostly buildings in this case).

harcher, what is really the source here? It is being uploaded too fast for manual tracing, which makes it seem like an import. And "source" is probably not "Digitalglobe", because the features do not align to either Digitalglobe Standard or Premium. They do align, however, quite closely to Bing.

So, just to wrap this changeset discussion; it spun out of control to attempt discussion of a lot of things besides its subject, the changes herein. In cases where the local preference is for some unusual interpretation of OSM's tags, it's advisable to just leave it as-is. There is enough to fix in the rest of the planet.

Hi, this changeset seems to create 6000 new nodes. Are you sure that it is "fixes and merges"? Merging usually results in deleting, not creating nodes. What exactly is this changeset doing?

velmyshanovnyi, you indicated "source=Bing" here, but the features are not from Bing. See for example: https://i.imgur.com/CVUVAo8.png Are they actually from LandSat or something else? If they are actually created using "scanaerial" from LandSat, then that should also be noted in your changeset.

My recommendation:
1. Either remove all the bad landuse, or use a JOSM filter to hide it for step 2.
2. Align the roads and fix the road topology!
3. Only then, you can gradually start to add landuse, carefully, bit by bit, checking and correctly each batch before upload.

Yes, I have read the "County Page". As for "nobody has said so in Santa Cruz County, where we have been doing this for at least 8 years", if nobody has pointed out that this data is mostly wrong, then it's only because nobody has looked, which is highly believable since there appears to be no actual data here, ONLY IMPORTS. Look at the Tiger ways! E.g. "Happy Valley Road" where the nodes are up to 100m off. 100m! Aligning the Tiger to reality is among the first steps to do in any part of the USA. It's the first thing I did in San Ramon. Sadly, nobody has done it here, which would explain that nobody has also noticed that the landuse is largely fictional.

Also, somebody foolishly imported fields like "Shape_area" which will be wrong the moment that somebody comes along to fix the polygons. What on earth is the point of that? Surely nobody expects general OSM users to update the useless "Shape_area" when the move the nodes into a more correct version? I strongly recommending deleting these spurious "Shape_*" tags. Also, "attribution" and "source" tags belong on the changeset, NOT the way; they next person to come along is not going to change every since "attribution" tag, so they have no purpose except to be soon wrong.

(...is better than...)

"you can use Bing (and a guess and a prayer) to better define landuse than does our County GIS department?"

If the County is marking forest as non-forest, and non-forest as forest - which they clearly are here - then absolutely. Detail based on aerial is based on detail that is just wrong.

I have now spend some time in the Happy Valley area to expand the natural=wood relation down from the hills to fill in where there is actually wood, which is most of the area left blank by the "farmland" removal. I also validated the relations to solve overlaps and degeneracies.

As for "removing it without replacing it with anything better", if you have a large area marked "D" which is actually A, B, C, then removing the wrong "D" IS actually better, because it is actually less wrong.

Hi Steve, since you expressed concern, I took another look at this area in detail. It is a total mess. The so-labeled "farmland" was not just wood and residential, but also some meadow (redundant overlap), and adjacent to existing natural=wood which is, in turn, actually residential in parts, and has overlapping meadow! In short, many of the larger imported polygons are inaccurate to the point of being completely useless and inaccurate. What's worse, their presence discourages anyone from actually putting the correct landuse in there, because a new correct landuse would get tangled with the old incorrect landuse. The one farmland I removed is only the tip of the iceberg of what needs to be wiped and re-created here. Do you have a better suggestion?

Hi, thank you. I'm not sure what level of detail that will produce, but, it sounds much better, and appropriate for remote regions. In OSM we usually speak of zoom level (e.g. 15), or meters of error on simplification (e.g. 0.1-1m). Perhaps by "40-50m" you mean the number shown on the scale bar in the upper-left of JOSM window.

In case you don't know, the setting for Simplification in JOSM is: Settings, Advanced Preferences, search for "simplify-way:max-error". For example, 0.8 is a reasonable value for hydrology, even in developed areas.

Hi, I ran simplify with a 90cm threshold. That is very conservative for a remote, wild area of mud and tundra. As for accuracy, I ran the JOSM validator and fixed many of the issues you left, with multipolygon ways intersecting each other, overlapping ways, and many other problems. It is fixed now.

velmyshanovnyi, PLEASE stop doing this. These features have way, way too many nodes - tens of thousands of colinear, inefficient, bad nodes. Please, please learn how to use Simplify to the correct level of detail. For these edits, I have to load them, delete most the points, and wait a long time for the deletion to upload.

Sorry i have no information on that highway. My own changes here are only on boundaries and waterways.

Diego, you seem to have added "natural=wood" polygons which are fairly arbitrary; they mostly contains forest but are more frequently contained inside larger continuous sections of forest, which makes them cartographically confusing (they do no correspond well). Do you mind if I replace them where possible with actual forest extent?

I have gone ahead and reverted this changeset and fixed all the geometry and topology it broke.