Further to my last, memories were revived, so a liitle more research done (I know, should have done it beforehand, but I' getting on and can't quite remember why I came here). There is a hamlet on the east edge of "boar woods", on the back cycle/walk route to Kevelaer named Laar (the aforementioned am Bruch is just south of Wemb). I can't see the stream being associated with Laar, as it passes through and around more significant settlements - which steers me toward the "quarry" option.