Two mapping questions

[SYO Member]

Can anybody say what is the correct way to portray the following on a 1:10,000 o-map? They don't seem to be included in ISOM 2000.

1. A 2.5m wide footbridge with a tarmac surface crossing a dual-carriageway or motorway. Should a bridge symbol (i.e. a reversal of 518 Tunnel) be used with a dashed path inside it? Should any colour be used between the dashes and the miniscule distances on the map between the path and the bridge lines?

2. The colour of the area between the boundaries of a railway line passing though woodland and open land. What about a wide triple line with embankments passing through woodland on a 1:5,000?

[Steve]

Can anybody say what is the correct way to portray the following on a 1:10,000 o-map? They don't seem to be included in ISOM 2000.

1. A 2.5m wide footbridge with a tarmac surface crossing a dual-carriageway or motorway. Should a bridge symbol (i.e. a reversal of 518 Tunnel) be used with a dashed path inside it? Should any colour be used between the dashes and the miniscule distances on the map between the path and the bridge lines?

2. The colour of the area between the boundaries of a railway line passing though woodland and open land. What about a wide triple line with embankments passing through woodland on a 1:5,000?

Railway lines? I thought the anorak discussion was on another thread

I'm feeling sorry for your zero replies, and although I'm not a mapper here's what I think as a competitor.

Firstly, if ISOM 2000 doesn't specify it, then there is no "correct" way, you just do something that is sensible.

Footbridge - as long as it looks like a permissible route it doesn't matter. It sounds narrow enough to depict as a symbol rather than actual size. I know of a footbridge over dual carriageway on the Campbell Park map in Milton Keynes, but I can't remember if it made it onto the reduced map used for the Sprint-O this year. Also - over the A3 at Longmoor / Woolmer, and over the A3 / M25 at Wisley Common. Check your map collection. (Apologies if I insult you as an anorak for actually having a map collection!)

Railway line - all pink hatched OOB, surely. Unless I don't understand your question, but either it's OOB or it's mapped as normal vegetation.

[mharky]

The railway lines on sprint maps should always be white and black. I think in OCAD it keeps the white areas anyway.

[SYO Member]

Thanks for replying. After a day and a half with over 350 views and no replies to this posting, it confirmed to me that there probably aren't any official rules. And as Steve says, in both cases you should just do something that is sensible.

[tokoloshe]

Sorry for the delay - not everyone spends all day browsing the web.
I think the option of the reversed tunnel symbol looks about right
I was going to put a picture of it here but couldn't work out how to do it - is it possible?