[OSM-talk] Big Lakes

[malenki]

I am working on Lake Nasser* and can predict that after enhancing
it's shore the resulting MP will be quite big. 
Based on what I have done so far I'd expect an Multipolygon (MP) with
about 10.000 Members and an outline of 14.000 km length. A relation of
this size is no good idea in hindsight of maintainability and conflicts
due simultaneous edits. 
So I thought about mapping it as coastline (again) and had a look at
how other big lakes were mapped.

I was a little astonished after having had a close look at the Big
Lakes in Northern America. They are mapped this way:
* outer ways and most of the islands are natural=coastline
* all of them and some additional islands included in three MPs for
  three of the five lakes¹
* for Lake Ontario, there is also a relation=collection² with a note:
  "Should be an enclosed way if not please check for gaps"
  Even though this isn't the case at the moment rendering is just
  fine.
 * additionally this relation contains three "help" ways created for
    making the ring of the collection and the MP complete
* there are some collection relations named e.g. "Southern Shore of
  Lake Ontario" whose intention I understand.

Now my questions:

What do you think is the better way to map an updated Lake Nasser?
Make another MMP (Monster MultiPolygon) or
map it as coastline (which is discouraged in the wiki)?

Regarding the Big Lakes:
At the moment they are mapped with coastline /and/ partly as MP.
Although my first guess that this was made to make them break more
easily may not be correct I think one way to map them should be
sufficient. Which way they should be mapped and who wants to take care?

I think we all agree that the collection of the outer ways of Lake
Ontario and the "help" way only member of this relation should be
deleted.

curious about the answers –
Thomas.


* http://www.openstreetmap.org/#map=9/22.8572/32.5566

¹
Lake Ontario: https://www.openstreetmap.org/api/0.6/relation/1206310
Lake Huron: https://www.openstreetmap.org/api/0.6/relation/1205151
Lake Erie: https://www.openstreetmap.org/api/0.6/relation/4039900

² https://www.openstreetmap.org/api/0.6/relation/1740344

³ 
https://www.openstreetmap.org/api/0.6/relation/1205133
https://www.openstreetmap.org/api/0.6/relation/1205140