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Fourteen Locks, Cefn
Monmouthshire Canal, Rogerstone, Newport, Wales, UK
Fourteen Locks, Cefn
associated engineer
Thomas Dadford jnr
date  1798
UK era  Georgian  |  category  Canal/Navigation works  |  reference  ST277886
ICE reference number  HEW 798
photo  courtesy Ray Haydon, MBACT Archive Officer
Fourteen Locks are the most spectacular set of locks in south Wales. They are located east of Rogerstone on the Crumlin Branch of the Monmouthshire Canal. The deep locks are separated by short lengths of canal with side pounds, as well as header ponds between groups of locks, to maintain water levels through the flight. Five locks have been restored so far (2014).
Thomas Dadford junior (c.1760-1801) was engineer for the Monmouthshire Canal between 1792-98. It was constructed for transporting coal, iron and limestone from the valleys of south Wales to Newport, and to the Bristol Channel.
The canal was built with two routes of 11 miles each — a main line between Pontnewynydd, near Pontypool, and Newport (completed 1796) and a branch from Malpas, north of Newport, to Crumlin now in Caerphilly (completed 1799).
The Fourteen Locks are located on the southern section of the Crumlin Branch, also known as the Risca Canal. The series consists of a top lock (No. 21), a triple set (Nos. 10-12) and five pairs of locks (Nos. 8, 9 and 13-20). The total drop is 51.2m in a distance of only 800m, top to bottom, or an average water level drop of 3.7m per lock.
The flight accommodates canal boats 19.7m long and 2.8m wide, carrying up to 28 tonnes of cargo. The locks have unusually deep masonry chambers constructed with arched floors for added strength. The associated culverts and spillways are also of the same red sandstone masonry. The canal cut is lined with puddled clay for watertightness.
The canal through the flight is surrounded by an elaborate system of side pounds, header ponds, sluices and spill weirs intended to conserve water in the operation of the locks. For example, for the byewash at Lock 17, a culvert in the side wall of the lock chamber conveys water under the towpath and feeds a steep weir that channels water into a second culvert leading into the pound of Lock 16.
The chamber of Lock 11, in the centre of a group of three locks, is unique in the Cefn system. It widens out at the top, forming a stone shelf on each side of the deep central channel. The date of construction of this configuration and the reason for it are unknown. At Pensarn Bridge (ST283885), the towpath changes from the north to the south side of the canal.
The locks were so busy that gas lighting was installed to allow 24 hour operation, though horses did not work at night and men had to manoeuvre the boats along the flight.
During the 19th century, as railway networks developed, more freight was carried by rail and canal transportation became less viable. By 1930, the Crumlin Branch was largely out of use and it closed in 1949. The locks fell into disrepair and their timber gates began to disintegrate.
In 1978, a visitor centre opened close to the pound between Locks 21 and 20. It was built as a small canal museum. The visitor centre was rebuilt, re-opening in May 2008 with interactive exhibitions and a cafe, managed by the Monmouthshire, Brecon & Abergavenny Canals Trust (MBACT), who kindly supplied the image above. The photo shows the foot of the lock flight and was taken in about 1920.
In 2002-5, Lock 21 was restored and repointed and in 2010-11, Locks 17-20 and their pounds were completely restored with grants from the Heritage Lottery Fund and other bodies. The monies also funded the centre’s Education Through Restoration project (2009-14).
The remaining locks are also to restored to full working order. On 22nd April 2013, a plaque was unveiled at the Fourteen Locks Canal Centre to commemorate Dadford and his achievements.
Fourteen Locks is now a scheduled ancient monument, listed by Cadw. It lies within the Monmouthshire & Brecon Canal Conservation Area, designated on 21st January 1998. The canal towpath is part of National Cycle Route 47.
Research: ECPK
reference sources   CEH W&WCEH Wales

Fourteen Locks, Cefn