Bosley Lock Flight

Bosley Locks

Bosley lock 4, with the top mitre gates of lock 5 in the distance.
Waterway	Macclesfield Canal
County	Cheshire
Maintained by	British Waterways
Operation	Manual
First built	1831
Length	70 feet (21.3 m)
Width	7 feet (2.1 m)
Fall	118 feet (36 m)
Above sea level	top lock: 518 feet (158 m)
Flight of 12 locks

Bosley Lock Flight (grid reference SJ904662) is a flight of twelve canal locks, situated on the Macclesfield Canal at Bosley, near Macclesfield, Cheshire, England. The locks are substantially built with stone blocks, and unusually for narrow locks have mitre gates at both ends. They were each built with a side pond, which enabled some of the water to be re-used during a filling and emptying cycle. The side ponds have been disused for many years, but there are plans to reinstate one of them for demonstration purposes.

The Macclesfield Canal was authorised by an Act of Parliament obtained in April 1826, after the civil engineer Thomas Telford had produced two reports and estimated that the canal could be built for £295,000. He also selected which of the contractors who tendered for the job should be awarded the contract, but his involvement then ceased, and the construction was supervised by William Crosley, the resident engineer. The quality of the workmanship was excellent, and by the time the canal opened on 9 November 1831, the total cost was only slightly more than the estimate, at £320,000. Like many of Telford's designs, it used cuttings and embankments to maintain as straight and level a course as possible, and this enabled all the locks to be built as a single flight, although there was also a stop lock where the canal joined the Hall Green Branch of the Trent and Mersey Canal at Hall Green. The contractors who built the locks were called Nowell and Sons.

When the canal was opened, there was also a stop lock at Marple Junction where it joined the Peak Forest Canal, but this stop lock has long since been degated, and only a narrow section with remains of the A-frames betrays its former existence.

When built, the flight was designed to be operated by two lock keepers. One had a cottage at the top of the flight near lock 1, and the other near lock 11. The top cottage is still there, but the bottom one has been demolished. The locks are built out of large stone blocks, and these were quarried near the bottom of the flight. Although there is no trace of it now, it is thought that a tramway brought the blocks from the quarry to the locks. In the 1950s, a reservoir was built in the disused quarry.