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I want to create a multipolygon water area. I have two lagoons that are outlined with NOAA Shoreline including central islands. The area is already a multipolygon but the two lagoons are not separated. I want to separate them. I've tried drawing a line and connecting it to the shoreline vector but I can't figure out how to partition of each separate lagoon.

There is also a large bay that I want to close off from the ocean that is lined with NOAA shoreline vector that is not set as a multipolygon area.

Basically, How do I create a multipolygon using existing vectors plus a new connecting vector, and how do I split an existing multipolygon into to separate multipolygons?

Can this be done using the ID editor or potlatch2?

asked 06 Jun '13, 18:50

EGhost57's gravatar image

accept rate: 0%

You can do it with Potlatch2, but not (yet) with iD.

If you have a look at this page, and read down to the "Potlatch 2 example", you should see some pictures that explain the basic process. To do what you're trying to do, you'll also need to split and rejoin some ways too.

Your area is slightly complicated because you're dealing with coastline, which doesn't get updated as often on the "standard" map rendering as other features (see some of these previous questions for details).

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answered 06 Jun '13, 19:41

SomeoneElse's gravatar image

SomeoneElse ♦
accept rate: 16%


Thanks for pointing me in the right direction. As a beginner I am extremely impressed with the helpfulness of the community thus far.

(06 Jun '13, 20:42) EGhost57

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question asked: 06 Jun '13, 18:50

question was seen: 3,738 times

last updated: 06 Jun '13, 20:42

NOTICE: is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum