[email protected] wrote: >Sent: 11 November 2009 12:49 PM >To: [email protected] >Subject: [OSM-newbies] Small streams under minor tarmac roads > >Greetings, > >What is the standard way of mapping small streams under rural minor >unclassified roads? > >If I'm standing on a bridge, however tiny, it's a bridge! > >However, in my area there's loads of streams criss-crossing the countryside >and I'm not at all sure how to map a stream, which often dries up in >midsummer, which goes into a smallish diameter - 600mm - concrete pipe >which then passes under a tarmac road, about 3 metres in width, and >reappears the other side where the stream continues it's way on the >surface? > >I've considered pipeline and tunnel but don't think their use applies here? > >Any advice please? >
There is usually an easy way to tell what the structure is. If you look at where the water disappears and re-emerges you should see one of the following: 1. A circular pipe, often of concrete but perhaps also of corrugated/galvanised steel. 2. A rectangular concrete culvert, basically a pipe but a regular rectangular shape. 3. No clear structures but perhaps bricks at each side and possibly no bottom. Cases 1 and 2 I would tag as a "culvert" because that's the technical engineering term for them. So culvert=yes and level=-1 perhaps. This is unlikely to render currently but only needs good support of tagging to see that change. Case 3 will normally be a bridge and often bridges will also have a guardrail/parapet on each side of the road where the bridge crosses the stream or drain. Watch out though because some form of barrier may also be present above a culvert to protect folks and vehicles ending up in the ditch. Hope this helps Cheers Andy _______________________________________________ newbies mailing list [email protected] http://lists.openstreetmap.org/listinfo/newbies
