A Brief History of the Somersetshire Coal Canal

The Somersetshire Coal Canal (SCC) was authorised by an Act of Parliament in April 1794.
The canal was promoted by the mine owners of the North Somerset coalfields as a cheaper means of transporting their coal to the markets in Bath and the surrounding area. (At that time the only transport was by pack-horse or horse and cart, over rough terrain. These animals could only cope with limited quantities, which resulted in high prices ).

The mine owners were also worried over the possible effect the flood of good Welsh coal might have on their market for there had been plans to import such coal into Bristol

Surveyed by John Rennie (of Kennet & Avon Canal fame), with help from William Smith (1769-1839) - (the "Father of English Geology", whose writings influenced Charles Darwin); the canal was to have two arms, with connecting tramroads, to the many coal pits in the Radstock and Timsbury areas.

(June 2001) A new and very-well reviewed book has just been published on William Smith.


(The book is:"The Map that Changed the World" by S Winchester. Penguin Books)
William Smith also built a
tramway at Tuckingmill . I have marked the route on my Googlemaps feature


The original plan was for there to be a 3/4 mile tunnel at Combe Hay but this was later rejected becasue of cost and thus the canal became a "summit"canal. One problem with both of these arms was the climb/fall of 135feet.

Starting at Dundas Aqueduct, on the Kennet & Avon at Limpley Stoke, the main arm would pass to the west through Monkton Combe, Midford, Combe Hay, Dunkerton and Camerton to the basins at Paulton and Timsbury. At Midford the other arm would head towards Radstock via Wellow and Writhlington. The Paulton arm (or sometimes called the Dunkerton line) was constructed at two levels, the upper level from Paulton to Combe Hay, and the lower level from Combe Hay to Limpley Stoke. In later years, at the top of the Combe Hay part was a steam pumping engine (see later). However, at first, to "bridge" the daunting difference in altitude between these two parts, there were to be the three
Caisson Locks (pic) at Combe Hay.
(Picture from The Daily Telegraph... "How the lock worked 362 kb file"; permission appied for).

These were experimental locks consisting of a large masonry chamber or 'cistern' in which a watertight box - the Caisson - was suspended. This box was large enough to take a full length boat, which was floated into it and then, with the doors closed, was raised or lowered to the desired level.
Adrian of the SCC has now completed an excellent series of diagrams to show how it works.
Adrian's Caisson "how it works"


Although the maker - one R. Weldon was able to demonstrate the whole mechanism in working order, it was not a success. It is thought that this was because of the Fullers' earth rock stratum in this area. It, (like Cat Litter) swells when in contact with water; the masonary walls must have buckled and trapped the caisson. History & further details. It was replaced by an inclined plane (Nov.1801).
This appears to have been the normal double acting type where coal was craned from the barges in wooden containers capable of transporting about 1 ton of coal each. Three of these were placed in each wagon. This wagon descended by gravity, the 300 yards in 5 mins, pulling up empty waggons from below by means of a continuous pulley system with the heavy chains passing around two equal sized wheels at the top and bottom.

Excvation of a possible site for the caisson is now taking place. This lock was one of the "wonders of the waterway world"; its exact construction and mechanism is unknown.
No matter how excited you may feel over its potential discovery please note that the site is on private land!

The inclined plane at Combe Hay was also unsuccessful, mainly due to the time consuming and inefficient trans-shipment of goods, and was eventually replaced, in April 1805, by a flight of twenty two locks, ( 3 had already been built near the bottom of the inclined plain).
One part of this new and costly venture was shaped like a bull's nose - still to be seen today. (See map). The large loss of water necessitated the building of a Boulton & Watt
Steam Pumping Station capable of lifting 5 000 tons of water in 12 hours. It needed a water supply -probably from lock 19. From here it is proposed that an underground adit (with a fall of 1:40) took the water up the 'middle' of the bullnose to the engine.


This pump was later dismantled and moved to Dunnkerton to join a near-identical partner. If you click on Dunkerton pump you will see it (to the left). (Len Bampfylde collection)
Nearby was
Dunkerton Wharf c1900. The cut from the coal filed to here was the first part to be opened and within 6 months 2 wagons per day were hauling coal from the wharf inro Bath at a cost of 2 shillings per ton, much less than previously.

We believe we have found the route of the adit! See:Adit map
Adrian writes:

"You will now find it is drawn straight and with two intermediate shafts - This is because Richard Hignett came up just before Christmas and found the spoil heaps from what appear to be the intermediate shafts. It all adds up to a straight adit. A very exciting find because it was made from a prediction based on engineering calculations, we didn't just blunder about and trip over the shafts. Richard actually reasoned where they should be and went straight to them. We are kicking ourselves for not spotting them before, one of them was only yards from where we were moving wood; but, of course, we didn't have his knowledge".

As you can see, this area at Combe Hay, is a very interesting one to say the least.
Please see:

Click here for a detailed look at the history of Rowley Bottom and how the Caisson worked.

For some time we thought there was (good) evidence that the engine was built on the site of the old caisson,

(You may wish to compare this with a B&W blow-up of part of a redrawn 1810 map. If so, press this link:redrawn 1810 map around Caisson House

If only the SCC had waited until late 1800 they might have been very impressed by a "balance lock" invented by James Fussell IV (of Fussell's Ironworks fame) and built at Barrow Hill near to Mells on the
Dorset & Somerset Canal . This was similar to the il l-fated Weldon design but had two caissons, in counterbalance, separated by a masonry wall.The inclined plane and extra locks might never have been! One site at BarrowHill has been excavated (July 2004)

(Caissons were also built on the not-too-distant
Great Western Canal)

However, another, untapped (?) source has been found. This suggests that the first caisson was soon modified and that it and the "second lock" were much more like the design of Rowland and Pickering! Hard to believe I know! For more detail see:
History & further details.

Why are there no pictures from this era? Because the world's first photograph by the Frenchman Niepce was not taken until 1827. Even then long-term fixing of the image was impossible. This had to wait until Daguerre's work in Paris 1839. Sorry!

The Society has actively conserved most of these locks. Although all wooden structures have long since gone, all the walls etc are intact. Regular working parties are held at the site. See later for details.

As to the other "arm", there are conflicting records as to its (economic) success. Engineering features include the tunnel near to St Julian's Church, recently excavated, and the sharp turn near to
St Julian's Well. During this time (1805), the length of canal from Radstock to Twinhoe was built and to avoid the expense of further locks to take the canal downhill to Midford, a tramway was built.
Again, because of the trans-shipment of goods at Twinhoe and the low level of traffic on this branch, it was eventually decided to extend the tramway all the way into Radstock, using the towpath as the bed of the track.
Pics of Twinhoe basin ...now (&then?)This was 7 1/4 miles long, single track, with passing loops every 600yards. Teams of 3 horses would haul 8 or 9 wagons of about 11cwt each.

This would leave the only trans-shipment point at
Midford Basin where this Radstock tramway and the Paulton canal arm met, converging over an aqueduct. (See the following pair of pictures)...and how it looks now after restoration!


Midford Aqueduct...






The canal was one of the most successful in the country, and in the 1820's was carrying over 100,000 tons of coal per year. However this prosperity was soon to be halted by the coming of the railways.
The opening of the railway line between Radstock and Frome started the decline in the canal's fortunes, by taking away the tramway's coal trade and eventually, in 1871, the tramway was sold to the Somerset and Dorset Railway who built their Bath to Evercreech line over much of its course.
(Picture to show. The tramway was to the right of the S&D rails. Twinhoe. The Bristol and North Somerset Railway's Hallatrow to Camerton branch of 1881 further eroded the canal's trade on the Paulton arm.
With trade increasingly being taken by the railways and, the working out of the coal seams, combined with fall in trade from the Kennet & Avon (itself suffering from railway competition), it was not surprising when the canal company decided to close the canal. The official liquidator tried to sell the canal as a going concern in 1894 but to no avail, and the canal eventually closed in 1898. In 1904 the abandoned canal was sold to the Great Western Railway, who in 1907-10 built the Camerton to Limpley Stoke Railway over much of the northern, Paulton, course. The tunnel at Combe Hay was drained and used as a railway tunnel instead.

By 1951 the GWR branch line had closed and in 1966 the S & D closed too (both losing out to road transport).

Today, there are few canal bridges that survive and of the twenty two locks at Combe Hay, eighteen are still there (although only seven are accessible to the public). The Midford aqueduct that used to lead to the trans-shipment basin is still there (and has been renovated, or see above), and the outline of the Paulton basin is still recognisable. above


Above - the packhorse bridge at Midford

One of the pairs of lock gates at Combe Hay(Waterways World Picture)

At Dunkerton, this tunnel (above) took the canal beneath the Bath to Radstock road. (See next- to the right)

..soon followed by this, an aqueduct.


500 yard section of the former SCC at Dundas Aqueduct has been restored for use as private moorings for the Kennet & Avon Canal.

At the junction of the K&A and the SCC the accommodation bridge has gone (replaced with a metal swing bridge), and the SCC decreased the width of the lock from Broad Guage to Narrow. We don't understand why this was done!

A museum, restaurant,and boat hire, at nearby Limpley Stoke has recently opened. (At the bottom of Brassknocker Hill).

See picture to the left.

(Pictures of the lock gates, Midford Aqueduct and the Brassknocker Centre have been taken from the Oct. 1998 "Waterways World". I have been assured that 'this is OK'. However if there are any objections please let me know)


The Wellow tunnel near to St Julian's church has now been excavated; both entrances are now clear and part of the basin has been exposed. However both entrances are on private property. A well-preserved part of the bed is nearby - at the back of the local school.

Picture to the right is of the Southern entrance. St Julian's Church is in the background

Many villagers have remnants of the old tramway rails. One even turned up during the restoration of the S&D Wellow station in 2000.


Wellow tunnel (sth end)