Cemlyn Canal

Cemlyn Canal
February 2016

The Cemlyn Canal.... Cemlyn Canal, I am not sure I have heard of that one I hear you cry.

Well, as an enthusiast of obscure derelict waterways my ears pricked up when my brother mentioned his discovery of an abandoned waterways near the western end of the Welsh Highland Railway.

Cemlyn Canal terminus

This fascinating discovery was tucked away in my memory and filed for exploration when we visit friends at their holiday home in Criccieth. A weekend visit rolled around and much to my pleasure I realised that our route in took us right past the canal remains.

Cemlyn Canal bridge

This short tidal waterways extended the navigable extent of the Afon Dwyryd to a loading wharf at Maentwrog,  312 yards upstream from a sharp bend inthe river. There were no locks, one bridge, two wharf's and only navigable at high tide.

The canal was cut in 1823 to pick up slate from the local quarries in the Ffestiniog area and operated for just 35 years before sliding back into obscurity reverting to its original activity as a drainage ditch. 

The canal was really one long quayside known as Parry's Wharf from which slate was loaded and dispatched to markets via the river estuary. The channel was an excavation of an established stream and even in its heyday it was too narrow for boats to turn or pass.

To get a feel for the maximum dimensions of the craft using the canal you only have to look at the solitary access bridge which remains in situ in its original format, and under which boats had to pass with their masts lowered. Its safe to say that this canal was a waterway for small craft only, but looking at the depth downstream in the Afon Dwyryd Navigation it was only ever capable of carrying shallow drafted boats.

 Cemlyn Canal Junction

Afon Dwyryd Navigation

Historical records indicate that boats on the Dwyryd were operated by two men and carries an estimated six tons per boat, which was little more than the diminutive tub boats (20ft x 6ft) used in the Coalbrookdate area. A typical month would have seen maybe 43 boat movements from the wharf representing over half the boat traffic on the river.

The main motive power would have been the ebb and flood of the tide, supplemented by sail whenever wind conditions permitted. The boats would have grouped waiting for the tide and then been swept down the river navigation to coastal craft waiting out at the mouth.

As with most canals, the construction of the Ffestiniog Railway killed the canal trade with the monthly canal volume contained in just 120 wagons. This move to rail was driven by simple economics with boats charging 15 shillings per ton vs six shillings on the tracks pre steam and falling to 2s 6d per ton when hauled by the new locos in 1864.