Reports from our Talks Programme
by Peter Keen

The River Weaver and the Salt Trade — a Talk by Colin Edmundson

The speaker for the Society's October meeting was Colin Edmundson, an author and authority on the River Weaver and the Salt Industry in Cheshire. Initially he had no interest in either topic but following a few sessions piloting a friend's boat on the river, he became more involved and ended up delving deep into historical archives to discover more. SCARS was able to reap the benefit of his research through his presentation.

The Weaver was a major transport route, with access to the port of Frodsham for vessels of up to 30 tons. By 1720 the port was despatching 7000 tons of Cheshire Cheese annually to London and it housed corn mills, salt works and boat building yards. The following year an act was passed authorising the making navigable of the River Weaver, in the face of much opposition from local people. This was rather strange since there was an increasing demand for coal from the salt industry and the need to distribute the refined salt to markets so a better transport route would surely have been advantageous. The driving force was in fact the demand from London. Accordingly timber locks were built at appropriate places with weirs alongside each, separated by an island or 'feather'. Cargoes could then reach Northwich where they could be transhipped to pack horse trains to travel south or stored in warehouses until transport became available.

In 1750 Liverpool merchants took over the navigation, intending to improve its facilities and make more money. The Sankey's Henry Berry was responsible for the building of one of the locks but unfortunately he built on quicksand, the lock sides moved, the water blew under the structure and the whole thing collapsed. Needless to say Berry was not invited to carry out any further work for the navigation owners. By 1781 some locks had deteriorated so new ones were built alongside, both sets being used whenever possible until the older ones became inoperable.

In 1777 the Trent and Mersey Canal was opened which drew some traffic away from the navigation. Boats could be loaded at Frodsham then travel along the canal to the Midlands without any transhipment being needed, thus reducing costs and curtailing the business of both Northwich and Winsford which had become a port serving the Potteries. However there was for many years sufficient business for both waterways, the river becoming quite congested by vessels waiting to lock out onto tidal waters. To eliminate this delay, new locks were constructed nearer the sea in 1781.

When steam power was introduced to the navigation in the early 1860s it became clear that a powered craft could tow a number of other vessels very efficiently. The problem was that the locks caused hold-ups as the boats were taken through one at a time. To combat this a programme of lock rebuilding commenced so that a 'steamer and its three flats could all pass through the lock at the same time. These new locks were quite unique in that their gates were operated by turbines built into the side walls of the chambers using the power of the river.

For many years salt and other cargoes had to be transhipped at Anderton where the Trent and Mersey Canal came within a few hundred yards of the Weaver. To eliminate these costs, the Anderton Lift was opened in 1875, joining the two waterways. Now the whole boat could be raised or lowered from one to the other.

Other improvement followed over the years. Deeper locks were built, reducing the number to be negotiated thus speeding up the journey time along the navigation, the course of the river was altered many times reducing the actual length to be travelled, massive sluices were built so that the water levels could be efficiently controlled and when the Manchester Ship Canal was built across the seaward end of the navigation it provided non tidal waters of constant levels instead of the previous variables. All these improvements allowed larger sea-going vessels to access as far inland as Winsford, but it never developed as a port.

Other unique features of the navigation were/are the bridges in Northwich. The very reality of subsidence meant that building a traditional bridge would have been impractical since the river banks could have moved and the bridges collapsed. Instead bridges were built on circular floating pontoons which allowed the bridge to be operated independently of the banks, with adjustment available where the bridge roadways met up with the actual roads. (Left)

During WW1 there was a shortage of timber so that maintenance of the bridges across the various side streams which entered the river could be a problem. One of these needed complete renewal but large timber was not available. Instead, thin layers or laminates were glued together to form the required beams which could then be assembled into the finished bridge, still functioning today.

Colin then turned to the early rock salt mines, mainly situated to the north of Northwich in the Witton Brook area. Here, between thick layers of marl lay two main beds of rock salt which could be mined via narrow shafts opening out into underground galleries. Most were small scale concerns, covering 3 to 4 acres, but other large concerns used narrow gauge tramways underground, the trams hauled by horses. Somewhat unpleasantly, it was learned that the narrow access shafts meant that horses were lowered down to the galleries whilst still foals, and never saw daylight again. When their working life was over they were slaughtered below ground and brought up to the surface in pieces.

The upper rock salt bed at a depth of around 100 feet was exploited first, miners digging long galleries through the salt, leaving salt pillars intact to support the roof, right. Unfortunately, all too often, insufficient support was provided and the mine would collapse, together with the rock strata above, leaving a hollow in the surface. Other extractors pumped brine up from the top surface of the salt deposits which resulted in further subsidence. As the brine pumpers had no control over what was happening below, land could subside long distances away from the actual mine sites.

The lower deposit at 300 feet was also mined, the salt being taken to nearby salt works for refining. Again water could enter the workings and dissolve the salt to form brine which could be pumped up to the surface. Collapses of the lowed salt beds caused massive subsidence at the surface forming huge craters which filled with water to cause further problems. The tale was told of the two youngsters sailing a boat on a lake in one of these flooded hollows. They noticed a disturbance on the water and swiftly landed on the bank. Shortly afterwards the bottom fell out of the lake creating a massive hole into which went many tons of earth and some of the local streams. They were very fortunate to escape an horrific fate.

Photographs were shown of the damage caused in the towns by subsidence. Roads could be broken apart just as they are during earthquakes in other areas. Brick buildings were torn apart as support was suddenly removed from one part of a wall. (Left) Whole buildings were shown to have subsided, albeit maintaining their horizontal position, so that anyone entering them had to step downwards onto what was the ground floor and was now more like a cellar.

Successful buildings were timber framed, on a massive timber base. In the event of any subsidence these buildings would retain their integrity even if they sank unevenly. It was then a simple matter of levelling up the building with jacks, usually borrowed from the nearby boat building yard. As Colin commented, it gave a whole new meaning to the term 'shop lifting'.

Some of the mines have been filled in during recent years in an attempt to reduce the risk of subsidence but many of the flooded hollows remain. Some have been filled in with dredgings from the river, chemical waste and even old canal boats. Local people with long memories can name some of the boats which survive now only as timbers emerging from the water.

Mention was made of the salt refineries such as the Lion Salt Works, where rock salt or brine would be boiled to form crystalline salt. They needed large amounts of coal and this came from two sources, the Staffordshire coalfields via pack horse trains and later the Trent and Mersey Canal and also from the South Lancashire coalfield via the Sankey Canal. The salt pans needed slow burning coal to maintain a steady temperature so were able to use low grade coal or even slack , a welcome demand for the coal owners of St. Helens. The Slave Trade Triangle is well known but less well remembered is the salt/ coal triangle of trade from Liverpool to St. Helens and over to the salt fields, carrying millions of tons of coal and salt over the years, bringing employment and prosperity to many.

Colin squeezed a mass of information into his presentation and it is hoped that he will be able to visit again to speak on other related topics.

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