`type=waterway` relations are flagged for having 1 member only

[Dimitar5555]

Item: 1200
Class: 12001
Example: https://www.openstreetmap.org/relation/6997571

Currently type=waterway relations with only one member are flagged for having only one member. This type of relation should be allowed to have only one member.

[frodrigo]

Why this should be an exception ? Do you have link to wiki or other think else

[Dimitar5555]

The wiki says that it's possible to have one or more rivers with role=main_stream or without any roles. https://wiki.openstreetmap.org/w/index.php?title=Relation:waterway&uselang=en