[Tagging] Underground power lines in tunnel

[fly]

Am 04.06.2013 11:15, schrieb François Lacombe:
> 2013/6/4 fly <lowflight66 at googlemail.com>:
>> On 04.06.2013 00:26, François Lacombe wrote:
>>> Hi,
>>>
>>> I'm currently improving draft of power transmission refinement proposal
>>> and a question about underground features can't currently find answer.
>>> http://wiki.openstreetmap.org/wiki/Proposed_features/Power_transmission_refinement
>>>
>>> I wonder how we can map power lines underground and infrastructure which
>>> can host them simultaneously.
>>> The best example is when several power lines are built in a tunnel like
>>> on this photo :
>>> http://www.rte-france.com/webapp/100ansparis/img/chapitre3/img14.jpg
>>>
>>> I can create several ways, very close from each other, for all power
>>> lines we can see and tag them with tunnel=yes but how will I map the
>>> tunnel ?
>>> If we only use tunnel=yes on each power line, it's impossible to know if
>>> they are in the same tunnel or if there is one dedicated tunnel for each.
>>>
>>> I think only a relation would solve the problem and it's not a power
>>> line dedicated question.
>>>
>>> Do someone have ever encounter that situation ?
>>
>> Mmh, type=tunnel is already in use [1] but it is used for the whole
>> tunnel, e.g. to combine several tubes and the infrastucture like escape
>> ways and air-system.
>>
>> We could use a tag like tubes= or number_of_tubes= for the relation and
>> draw the outline.
> 
> Type=tunnel can suits my needs : let's add all power lines in the
> relation with role=through.
> Add tubes or not depends on the tunnel design, not on what's inside. I
> don't mind.
> The trick is to link many power lines to a single tunnel.

Exactly, we need it for rails a lot as often several track run in one
tunnel but it is not often used.

With motorways you often find tunnels with two tubes but one name and
connections plus sharing escape ways.

> However, it would be hard to build something in transmission
> refinement with it since type=tunnel proposal isn't voted yet.
> Don't we have something more reliable ?

Sadly it is not used that often but it works quite well !

But tunnels are not well mapped across the globe (no gpx, no aerials).

Cheers

>> --
>> [1]
>> http://wiki.openstreetmap.org/wiki/Relations/Proposed/Bridges_and_Tunnels