At a bend in the stream a mile (1.6 km) north of West Kill, where the Shandaken Tunnel's visible surface right-of-way, along with a power line, cross the kill twice, Beech Ridge Brook flows in from the west. Immediately north of the bend, the West Kill crosses under Route 42, entering a section where both banks are shored up with riprap for the next as the stream and road again follow a north-northeasterly course. The natural banks return where Roarback Brook, the lowest tributary of the West Kill, flows in from slopes of Vly Mountain to the west.