SomeoneElse
It looks like there is a bit of river duplication here between http://www.openstreetmap.org/way/370922176#map=19/55.25316/-7.26563 and http://www.openstreetmap.org/way/352793498#map=18/55.25323/-7.26499 (and has been for some time).
Presumably the river is the boundary, but that needs aligning as best as can be.