I found a lot of lakes in Sweden which has natural=water but not tagged with any water= tags like water=lake. Most of them (est. 98%) are lakes.
I just wrote this https://josm.openstreetmap.de/ticket/18297#ticket
This resulted in one of my biggest changesets to date: https://www.openstreetmap.org/changeset/76657579
I have now found these tags missing on 3 continents Eurasia, Africa and South America.
Note: be careful with bays like this one as these are currently tagged with natural=water and no water tag because we have no suitable it seems. I add water=bay to these because they are not closed of like lagoons.
Note2: also be careful of riverbanks not tagged with waterway=riverbank.
Note3: My current workflow is this:
- download country or part of country (<100 mb) from geofabrik.
- use osmconvert and osmfilter to extract the natural=water and drop water= & waterway= tags. I use .poly files to extract smaller areas from the large country files. See https://wiki.openstreetmap.org/wiki/Osmconvert#Example_using_a_polygon_file_from_polygons.openstreetmap.fr for how to do that. An example command I use is: “osmconvert sweden-191107.osm.pbf -B=norrbottens-län.poly –complete-ways –complete-multipolygons -o=out.o5m && osmfilter out.o5m –keep=”natural=water” –drop=”water=” –drop=”amenity=” –drop=”waterway=” >out.osm”
- open the filtered .osm-file in JOSM
- inspect all elements to see if any are clearly reservoirs and add fixme tags to uncertain ones.
- search like this: “natural=water and -waterway=* and -water=* and -wetland=* and -sport=* and -landuse=* and -surface=* and -golf=* -fixme=* and (type:way or type:relation)” to filter out any strange water areas.
- add water=lake to the rest and source:lake=manual review based on MAXAR