Water levels of the Birmingham Canal Navigations

The Birmingham Canal Navigations (BCN), a network of narrow canals in the industrial midlands of England, is built on various water levels. The three longest are the Wolverhampton, Birmingham, and Walsall levels. Locks allow boats to move from one level to another.

Heights given are nominal elevation above sea level in feet relative to the Ordnance Datum Liverpool.

A former branch of the Wyrley and Essington Canal, the Essington Branch was abandoned before 1904 and is now filled in. It was the highest level on the BCN.

The highest canal currently in BCN, 1 mile of which remains navigable. It was fed from the 18th century Titford Reservoir (now under Junction 2 of the M5 motorway) originally by feeder, and since 1837 by the Titford Canal. A feeder from the Tat Bank Branch (also known as Spon Lane Branch) supplies water to Edgbaston Reservoir.

A historical level, no longer existing. The highest level designed by James Brindley for his Birmingham Canal (BCN Old Main Line). Removed by John Smeaton's design in 1790.

A total of 41.7 miles navigable without locks:

A total of 49.2 miles at this level (21.2 miles of which is on the BCN) navigable without locks.

Connecting canals, not part of the BCN, but using this level:

A total of 13.4 miles navigable without locks.

To keep the canals topped up with water, reservoirs were built to collect water from streams. These had to be above the relevant canal levels, often some distance away. The small Titford Reservoir (Titford Pool), as well as feeding the Titford Canal supplies its surplus water to Edgbaston Reservoir along a feeder through Smethwick. Water from Edgbaston Reservoir feeds the Birmingham Level at the adjacent Icknield Port Loop, and once fed the Wolverhampton Level via a long feeder (now overgrown and dry) along the top of a raised embankment along Telford's BCN New Main Line to the Engine Arm. Water is also supplied by Chasewater and Netherton Reservoirs.

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