Like https://osm.org/changeset/118501311 et al, surely this is Gunnerside not Grosmont?  We know there's an obviously wrong Yorkshire Water spreadsheet out there (see several previous on https://resultmaps.neis-one.org/osm-discussion-comments.php?uid=508 ), so I think we all have to check any names added against the "sniff test" - does this name look right for this place, or is it perhaps the name of somewhere else?
Cheers,
Andy