Thank you so much for your reply. Understandably you didn't actually realize that there were some consequences of your edits. This is one of them: https://overpass-turbo.eu/s/1QhN The whole coastline of USA was broken as a result. We were able to fix all these errors, you can see one of the changeset here: https://www.openstreetmap.org/changeset/155774125 By deleting coastline tags you were creating wetlands. The best way to create wetlands in this type of situation is to create a multipolygon using the coastline ways as a part of multipoygon while remaining all tags. Find more details here: https://wiki.openstreetmap.org/wiki/Relation:multipolygon