Hi there,

For https://www.openstreetmap.org/relation/17916558
https://www.openstreetmap.org/relation/17929831
https://www.openstreetmap.org/relation/17929830

These should not be waterway relations, waterway relations are for grouping waterways, not bodies of water please see the documentation here: https://wiki.openstreetmap.org/w/index.php?title=Relation:waterway&uselang=en

These three relations should all be multipolygon relations, for Two Lakes you should omit the stream connecting them since that will make it invalid.

Hope this helps!