for some time I’ve been watching a user adding “new areas” (mostly landuse) to the database. One of their countries of focus is Ireland where most of their edits touch about a gazillion relations. So before I decide on my further course in this matter I’d like to know how boundary relations are composed in Ireland. Are they supposed to be dedicated ways or can any kind of way (highway, waterway, landuse, …) be employed in boudary relations?
Hello there!
Is it myself by any chance (EM_OSM)?
Mapping landuse, especially farms, forests and bogs, I find that many of the field boundaries align to local boundaries such as electoral districts (administrative boundaries). In my older edits I used to follow the boundaries but more recently I have been disabling the boundaries layer on the map and setting the landuse feature along a ditch/hedge or roadside instead.
If administrative boundaries and landuse boundaries are supposed to be mutually exclusive then I’ll take that onboard. Feedback appreciated.
Hi
no. The user in question is most certainly from Germany and the account used to map the landuse in question has been silent since mid July. I have no idea why, though I suspect trouble logging in since they told me they don’t have access to the emailaccount used in creating the OSM-account.
Maybe they created a new account which in turn means that I would need to look for the same pattern in mapping if I were to keep an eye on them again.
Still my question to the Irish stands: Do you use landuse and highways as parts of boundary relations or is this frowned upon?
Those people may not be active in this channel, as suggested by the lack of an answer to the original question posted 24 days ago.
You might want to try one of the other channels listed on the openstreetmap.ie contact page - which I notice doesn’t mention this community forum.
(I am from Ireland but don’t live there, and my mapping in Ireland is usually confined to hiking routes, so I don’t have any expertise on boundaries, I just know that Ireland has an exceptionally large number of boundaries mapped in OSM).
Ireland has a very large number of small admin boundaries.
Most (neatly all?) are relation objects, composed of ways. When there is no feature on the ground (now) then a way with no tags will be used. But there are many examples of a river, road, wall, or hedge being a member of an admin relation.
I thiiiink there might be some legal admin boundaries which are (currently) defined by features like roads, so having a road in the relation is actually 100% OSM good. But lots of admin relations in OSM have (AFAIR) no legal written definition like that.
I don’t know if Ireland community has already hashed this out before, but in my opinion:
Pros:
Fast and easy way to map the boundary (…I guess. I don’t have first-hand experience of such)
Less duplication of lines in OSM
Eliminates the hassle when two lines are directly on top of each other and someone accidentally does stuff with the wrong line in their editor.
Makes it clear without doubt that the boundary is associated with said feature
Cons:
Makes it difficult to update an object that belongs to the boundary. For example in situations where the road has moved, but the associated boundary did not move: you have to decouple the road from all boundaries which stay on the former alignment.
Similar to above - makes it more likely that the boundary will be inadvertently damaged. I’d say many people simply won’t be aware, of whether the road belongs to boundaries that are based on the alignment of that road when the underpinning legislation was made or not. I wouldn’t blame them for not knowing this.
I have added a lot of landuse in Ireland. I don’t see a need to touch admin relations to add landuse, in fact I would avoid doing so. I would alter a relation when adding landuse if I see an opportunity to improve the accuracy of an admin boundary shape that happens to follow a landuse that I’m editing.
I guess I’ll keep an eye out for accounts that “look german” and add mostly landuse (especially orchards and construction sites) frome Ireland to Egypt and try to get in touch
Yep there are definitely admin boundaries that use roads in Ireland (and are mapped as such in OSM). And that use all sorts of other features (hedges, rivers,…)
I tend to favour tagging administrative boundaries on those physical objects, rather drawing lines. It see a lot of admin boundary lines on OSM, drawn years ago, that I’m guessing were imported from some dataset or other, and they often seem quite poorly aligned with satellite imagery…whereas most physical features and boundaries that get added are done with reference to satellite imagery, and so are probably more spatially accurate?
