Surface=fine_gravel - is it for loose gravel or duplicate of surface=compacted

It is still there. Any volunteers to change that?

The fine_gravel page reads like a description of compacted too. Maybe in German Engineering Feinschotter (fine_gravel) actually is what in OSM is called compacted?

I just put the Feinschotterweg picture up to surface=compacted as a sample. Maybe the originator of the photo is an engineer? Who to contact him?

compacted is a “compactable” material which means it NEEDS to contain corn diameter of down to zero (German: “nullanteil”). fine_gravel is non compactable which means it lacks corn sizes down to zero.

So compacted is something like 0-30 diameters where fine_gravel has 5-20 or something.

Flo

Sorry, I’m very late to this topic because I only discovered it through the WeeklyOSM newsletter.

I feel the most important thing about the surface designation is how it determines the ability of different users to use the route. People here keep mentioning cyclists but from an accessibility perspective, other very important considerations are people in wheelchairs and pushing pushchairs.

The precise surface is useful to know because people might be able to estimate whether to risk a route knowing how the surface degrades over time, but would it be as useful in the wiki guide for which tag to use to use the impact on different users? So I would say irrespective of the size of the stones, gravel and fine_gravel will be very difficult for cyclists, wheelchair and pushchair users for any significant distance. If they get mixed up, it wouldn’t be that critical, but mixing this up with compacted would cause more serious problems for users. compacted, regardless of the presence of gravel, fine gravel or stones, will be acceptable for such users. Then the smoothness key can will indicate issues like potholes, ruts and tree root displacement that would make even a tarmacked surface tricky for those users?

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The problem with the surface tags for unpaved surfaces is that many mappers do not have the expertise to distinguish between the available options and the more tags are available the more tagging mistakes occur. Add some poor descriptions in the wiki and you will have a mess after a short time. In my area some 90% of all compacted forest roads are tagged “gravel” because that is what people see. The surface is made up of a layer of gravel or crushed stone of different sizes. It is hard and compact but the gravel is still visible.

That is why I tried to make connections between the surface tag and the usability by non-motorized vehicles which could help to find the correct tag. Nevertheless it still remains tricky as there are no exactly defined differences. Each of the discussed tags is overlapping the others. And moreover the durability of unpaved tracks is depending on the scope of traffic. A well compacted forest track may deteriorate heavily during just a couple of weeks if lots of heavy machinery are passing during harvesting works.

A grade 2 track tagged with the correct surface + the appropriate smoothness should give any user a good idea about what they could expect but it still can’t be seen as a guarantee if your bike or wheelchair ride will be pleasurable or not.

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I totally agree - it’s almost like a simple flow chart with one or two questions and answers will help. So though a picture helps, asking “would it be easy to push a pushchair here without the wheels sinking into displaced gravel?” would be clearer… Or “How deep is the gravel before you reach a solid surface?”

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That’s exactly what I map as fine_gravel.

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In German, the most precise term for this is Splitt - you commonly observe this on pathways in cemeteries e.g. In winter it gets spread galore on footways to prevent people from slipping. In spring, it takes the municipal gardening department a tenfold the time to collect than what was spent in winter.

Split is made by crashing gravel, which in German colloquially is called pebbles,

Not for the first time, I’m thinking that it’s a shame that OpenStreetMap wasn’t invented in Germany but instead in the UK. The terminology used would have been so much more precise. :grinning:

Nah, I’d be cautious with such a statement, because German speaking engineers and common lads, self-made concrete mixers, and also Geologists, have quite different understandings of gravel (Schotter) and pebbles (Kies). In fact, opposite ones.

PS: Splitt is an English term :slight_smile:

In Germany we only invent such easy to use things like “Einheitliche Datenbankschnittstelle” (EDBS) and “Normbasierte Austauschschnittstelle” (NAS)

In Germany we have a single word for stable, sty, pen, cot and any other “building for animals”.
And if you say “umfahren”, it can mean to drive around and to drive over, the same word.

This is the precision of German :slight_smile:

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Pfff, whether you drive around or over something: you’re behind the barrier :joy:

Jokes aside, there are areas where German is more precise then English, but in some areas, it’s the other way around. At least OSM doesn’t force people to type umlauts :wink:

As an avid surface=compacted tagger that only recently started to use gravel and pebblestones for deteriorated compactions, this topic quite nags me.

I see two schools of thought, and wiki edits by Germans may very well nowhere made the waters less murky:

  1. fine-gravel is the water bound material subject to compaction used as a cover on lots of tracks, a mix of different size mineral compounds (which some German speaking engineers call Feinschotter, nearly a word2word translation).
  2. fine-gravel is the material mostly used in garden paths or outdoor seating areas (in German called Splitt, colloquially mostly called Kies though).

Browsing the web, similar distinctions can be found in commerce - e.g. Was ist der Unterschied zwischen Kies, Splitt, Schotter & Co.? | Blog | Schicker Mineral - a business that sells rocky materials. And indeed, they use size as a defining measure https://www.schicker-mineral.de/media/image/8b/f1/5b/36-uebersicht-sand-splitt-schotter-1.jpg - There I learned, that was called gravel in OSM until recently, is called Schroppen in German, though not from Germany, my native language :slight_smile: