In August 1955, flood waters from the Delaware River caused by Hurricane Diane washed out portions of the line north of Belvidere near where the right-of-way crosses modern-day US Route 46, although the line still remains active south of this point to serve the Hoffmann-LaRoche pharmaceutical plant. North of where the plant is now to the junction at Manunka Chunk, the line was subsequently removed in late 1955. On December 31, 1957, the Bel-Del was merged into the United New Jersey Railroad and Canal Company, with passenger services ending on October 26, 1960.