Question: The 39 mi long river which flows through the Irwell Valley in North West England and forms the boundary between Manchester and Salford meats what other river at Waterfoot, Lancashire?
Sentence (from "Waterfoot, Lancashire"): Waterfoot is a small Rossendale mill-town between Rawtenstall and Bacup in Lancashire, England, where the B6238 road from Burnley meets the A681 road.
Relevant evidence: No