[Talk-GB] OS VectorMap water feature import

[Chris Hill]

On 11/12/11 11:26, Borbus wrote:
> First of all, when I say import I mean a manual import: reprojection of
> OS shapefiles, conversion to OSM data and careful processing in JOSM
> before uploading.
>
> I'd really like to get all the water features from OS into OSM.  It's
> very useful data and also makes maps prettier.  It's quite a laborious
> task, though, as the data requires manual creation of multipolygons and
> of course merging with any water features we already have.
>
> I have already done a small amount here:
> http://www.openstreetmap.org/?lat=52.6006&lon=1.6362&zoom=13&layers=M
> Although I have not joined together all gaps, just some gaps where a way
> crosses it and it is obviously a conduit.
>
> Now I have split the Vectormap square TG into smaller chunks which I
> plan to process one by one and upload.  The amount of data in just this
> square is quite large, but it's still probably less than half of Norfolk.
>
> Have any large scale imports from this dataset already been done?
>
> Do people think this is a good idea?  Any suggestions regarding the process?
(Grrrr, and now to the whole list ...)

As always, I would say use the OS data for areas you know. So when you 
say 'all water features from OS' I hope you mean in an area you know and 
not the whole of Great Britain.  It does, as you say, need work, not 
least to bridge the gaps left from the process that generated it where 
anything crosses a waterway. Sometimes these are bridges but sometimes 
they are culverts or occasionally some form or viaduct or pipework or 
even real gaps. Some of the water features no longer exist. Some are 
ditches that only occasionally have water in them. Local knowledge or a 
survey is essential to use this data in a way to improve OSM rather than 
just dumping it into OSM.

Having said that importing the detail especially for a complex waterway 
can be useful and a substantial improvement over trying to trace it and 
would be very hard to survey with a GPSr.

If you just want OSM to look like OS, you could just use OS.

-- 
Cheers, Chris
user: chillly