[Talk-us] Great Lakes Boundaries

[Mike Thompson]

User maxerickson sent me this comment directly about this issue:

=====================

The current modeling of the Great Lakes is actually to use
natural=coastline.

The addition of natural=water to the lake superior relation is probably
what caused the bad rendering at z13.

If you check the history of the relation, you can see people repeatedly
adding and removing natural=water.

=====================

On Sat, Apr 18, 2015 at 1:05 PM, Mike Thompson <miketho16 at gmail.com> wrote:

> Jim,
>
> Isle Royale should be rendering correctly at all zoom levels. I added the
> ways that make up the island to the Lake Superior multipolygon relation as
> "inner" members *and* removed the "natural=coastline" tag from those same
> ways. According to the wiki [1], this is the current method for mapping
> islands that are within inland bodies of water (as opposed to islands in
> the Ocean).
>
> There are lots of other islands to fix, including other small islands next
> to Isle Royale that I believe are part of the National Park.
>
> I do have a related question that I will post to the broader OSM-Talk list
> as it isn't US specific.
>
> Also, there are a lot of topological issues within Isle Royale to fix
> (some of the lakes *on the island* overlap wetlands).  These don't seem to
> impact the rendering - other than the overlap looking bad.
>
> Mike
>
> [1]
> https://wiki.openstreetmap.org/wiki/Tag:place%3Disland#Islands_in_waterways_and_lakes
>
> On Sat, Apr 18, 2015 at 9:46 AM, Mike Thompson <miketho16 at gmail.com>
> wrote:
>
>> Jim,
>>
>> So far no tags have been changed, I only made sure that no
>> natural=wetlands extended into Lake Superior from Isle Royale.  I will work
>> on the "relation" aspect later.
>>
>> Mike
>>
>> On Sat, Apr 18, 2015 at 9:29 AM, Jim McAndrew <jim at loc8.us> wrote:
>>
>>> Mike,
>>>
>>> Thanks for looking into it! I'll look at how you changed the tags and
>>> maybe try fixing/breaking it myself!
>>>
>>> --
>>> Jim
>>>
>>> On Fri, Apr 17, 2015 at 6:13 PM, Mike Thompson <miketho16 at gmail.com>
>>> wrote:
>>>
>>>>
>>>>> I assume that should be natural=verywetland, yes?
>>>>>
>>>> Yes! - Good one!
>>>>
>>>> Jim,
>>>>
>>>> I fixed the wetlands that extended into Lake Superior.  The problem you
>>>> pointed out seems to have gone away. However, Above zoom level 12 Isle
>>>> Royale is flooded by the lake.  This is true of other islands within Lake
>>>> Superior (the exact zoom level varies at which this happens from island to
>>>> island).  I suspect that to do this right would mean making all of these
>>>> islands "inner" members of the Lake Superior multipolygon.  I can work on
>>>> this over the weekend... unless someone beats me to it.
>>>>
>>>> Mike
>>>>
>>>
>>>
>>
>
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