Monmouthshire & Brecon Canal

The canal's basin at Brecon

The canal’s basin at Brecon

Part of the route of the Canal

The Monmouthshire & Brecon Canal is a small network of canals in South Wales. For most of its 35-mile length it is in the Brecon Beacons National Park.

The “Mon and Brec” is actually two canals – the Monmouthshire Canal from Newport to Pontymoile and the Brecknock and Abergavenny Canal running from Pontymoile to Brecon.

The Monmouthshire Canal
This received its Act of Parliament in 1792. It originally ran from the River Usk in Newport (near the site of the present-day Riverfront Arts Centre) to Pontnewynydd, rising 447 feet through 42 locks. The maximum width for vessels was 9 foot 2 inches with a draught of three feet. There was a branch at Crindau which rose 358 feet through 32 locks to Crumlin (including the Cefn flight of Fourteen Locks). The engineer for this difficult and expensive route was Thomas Dadford. It was opened to Pontnewynydd in 1796, and to Crumlin in 1799.

The Brecknock and Abergavenny Canal
This was first proposed in 1792 as a separate venture, also beginning at Newport. The Monmouthshire proprietors invited their potential competitors to join at Pontymoile and share the navigation from there to Newport. From this junction, the Brecknock and Abergavenny ran through Llanfoist and Talybont. The Act was passed in 1793 and was level to Llangynidr where there were five locks plus another at Brynich.

Initially work concentrated on the railways and it was not until 1795 that Thomas Dadford was appointed as the engineer and construction began in earnest. Work began in 1796 and by 1798, the canal was open from Clydach to Llangunnider and much of the rest was in hand. However costs, as usual, were higher than expected and, in 1799, the engineer, Dadford, stated that a further money was needed to complete the section from Clydach to Brecon. Benjamin Outram was called in to inspect the work and to advise on substituting a railway between Gilwern and Pont-y-Moel. Outram recommended several improvements, in particular the partial rebuilding of the Ashford Tunnel. He was also somewhat critical of the, then existing, railways.

The canal was completed to Brecon in 1800, but it was 1805 before it reached Abergavenny, when the committee concentrated on running the canal and railways so far opened. By 1809 the Monmouthshire Canal was threatening litigation about the uncompleted connection from Gilwern. William Crosley was appointed to complete the work which opened in 1812.

Llanhiddel Railway
In 1798, the canal company agreed with Sir Richard Salusbury to build a line connecting his collieries to the head of the canal at Crumlin. It was not until 1800, however, that Outram was asked to survey the line. It was twin track and connected by means of an inclined plane to an existing line – the Beaufort Tramway – at Argoed. Outram was somewhat dismayed that they had not followed his designs to the letter, probably to save costs.

Sirhowy Tramroad
In 1800, the owners of Sirhowy Ironworks were granted permission to exploit the minerals under Bedwellty Common and build a tramroad to join the canal, with the erection of a works (which was later Tredegar Ironworks). They then extended the line to the River Usk near Newport, where it joined the canal. Since this bypassed much of the Monmouthshire Canal, running parallel to it, so the ironmasters agreed to connect to the canal at Risca. This however was rejected by the iron company shareholders and Outram was asked to survey a railway line from Sirhowy to the River Usk near Pillgwenlly. Branches would be built to the limestone quarries at Trefil (the Trefil Tramroad) and another to the Union Ironworks at Rhymney. A major feature of the line was the ‘Long Bridge’ at Risca, 930 feet long with 32 arches each of 24 foot span averaging 28 feet high. The bridge was abandoned when the line was converted to standard gauge in 1865 (sold, it is said, for £1 per arch) and demolished in 1900.

The canal today
Communities on or near the canal include:

On the main arm:

On the Crumlin arm:

The Taff Trail cycle route, follows the canal for a few miles from Brecon, but the path next to it after that is not suitable for cyclists.

There are plans to reconnect the southern end of the canal to the River Usk by means of a marina in Crindau which would connect it to the rest of the British canal network.