“WENDOVER, a market town and borough of England, in the county of Buckingham. It is but an inconsiderable place, consisting chiefly of mean brick houses, and possesses no trade or manufacture of any consequence, except lace making, from which the inhabitants derive their chief support. A branch of the Grand Junction Canal, called the Navigable Feeder, has been brought into the town, which may be of some importance to its trade.”

The Edinburgh Gazetteer, or, Geographical Dictionary (1822)

Navigating the Wendover Arm at Little Tring.

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WATER FOR THE SUMMIT

IN addition to the many construction problems facing James Barnes and William Jessop [1], the Grand Junction Canal’s (GJC) civil engineers, was that of locating sufficient water to flood the Tring summit (the Canal’s other summit at Braunston posed less of a problem).

During the canal carrying era, water shortages, when they occurred, adversely affected the flow of trade and the canal company’s revenue.  But keeping a canal flooded was often no easy task, particularly at high points along its route where obtaining sufficient water could prove challenging.  Here, the canal engineer had to resort to various strategies: seeking a route that avoided high ground so far as possible (which might involve excavating tunnels, as at Braunston and Blisworth); diverting into the canal what rivers, streams and drainage channels existed in the locality (which often gave rise to conflict with local water millers); and using steam-powered pumps to raise water from low-level sources, such as reservoirs, bore holes and lower sections of the canal itself.  Maintaining a sufficient supply at the GJC’s summit at Tring has proved a particular problem, for despite all the usual strategies having been employed, reports of low water levels adversely affecting trade during prolonged periods of dry weather arose throughout the Canal’s commercial life and continue to the present day. [2]

The Chiltern Hills, a 47 mile-long chalk escarpment, lie across the path that the Marquis of Buckingham commissioned Barnes to survey in 1792.  Confronted with this unavoidable barrier, Barnes routed the canal through the ‘Tring Gap’, a lowering in the ridge of the Chilterns that has been used as a crossing point since ancient times. [3]  Taking account of the likely traffic levels across the summit and the water requirement for lockage, it must have appeared that the springs that rose in the Tring Gap together with local drainage were unlikely to be sufficient and it was therefore necessary to import supplies from further afield.  As shall be seen, this task was to present its own challenge over many years.

The Chiltern Hills are composed of chalk, some 90 million years old.  Because chalk is porous, it absorbs and stores rainwater, in effect forming a massive underground reservoir (aquifer), which is maintained by a stratum of impervious clay (gault) beneath it.  Natural springs appear wherever the base layers of chalk come close to the surface.  At Wendover, some 6½-miles to the west of the Canal‘s summit pound, such a spring emerges at Wellhead, near to St. Mary’s Church, where water from a point at which the Coombe and Boddington hills meet wells up to the surface.  This abundant supply formed the Wendover Stream, which flowed northwards through the valley driving numerous water mills on its way to join the River Thame.  In the absence of a sufficient supply closer to hand, Barnes planned to divert the Wendover Stream into a channel, which was to follow the contour  eastwards along the northern face of the Chilterns intercepting other spring-fed streams en route [4] to join the main line at Bulbourne [thus ― unlike its near neighbour, the Aylesbury Arm ― the Wendover Arm is an example of a ‘contour canal’, one that by following the contour avoids the need for locks and (for the most part) other engineering work, such as cuttings and embankments].
 

Having received authority under the 1793 GJC Act to construct whatever feeders were necessary to obtain canal water, the Grand Junction Canal Company (GJCC) entered into purchase negotiations with local landowners and the inevitable water-millers to construct what at the time was to be no more than a feeder ditch.  To placate the millers, whose livelihoods would inevitably be damaged by the diversion of the Wendover Stream, the GJCC bought the water mills at Weston Turville and Wendover, and the water rights to the mill at Halton, [5] only then to find that other millers further downstream at Aylesbury were also affected.  To address this, a new reservoir was built at Weston Turville.  Eventually, the GJCC bought the Aylesbury mills, thus avoiding the need to supply them with ‘compensation water’.

Weston Turville reservoir lies about a mile to the north of Wendover town centre and adjacent to the Arm.  It accumulates water mainly from two streams below the level of the canal and from any overflow from the canal itself.  Built in 1797-8, it is the earliest and most westerly of the five reservoirs that lie along the foot of the Chiltern escarpment.  Although not intended to supply the canal, in 1814, following several years of poor water flow, a temporary Newcomen-type pumping engine was installed to raise water from the reservoir as and when required.  No clear information remains as to the capacity of this pumping station, but it is known that its outflow pipe into the canal was four inches in diameter.  Weston Turville pumping station remained in use until about 1838, and was eventually scrapped in April 1841.  Since then water has occasionally been taken for the canal during periods of drought, but today the reservoir is used for recreation.

Further to the east lie the four Tring Reservoirs.   They comprise Wilstone (1802, heightened in 1811 and 1827, and extended in 1836 and 1839), Marsworth (1806), Tringford (1816) and Startops End (1817).   Of these, Wilstone is by far the largest.

The opening of the GJC in 1800 [6] resulted in more traffic than had been anticipated, added to which the Aylesbury Arm (opened c. 1815) imposed a significant drain on the main line.   Consequently, the demand for water at the summit increased.  To address this, the Tring reservoirs were built in stages to provide further supplies, which they accumulated from local streams and any surplus from the canal itself.

The visible remains of Whitehouses pumping station.

 
Originally, the reservoirs were worked by three pumping stations located above them on the Wendover Arm; Whitehouses pumping station (between Drayton Beauchamp and Little Tring, capacity believed to have been 30 locks per day) worked Wilstone Reservoir, a pumping station near Bulbourne Junction worked Marsworth Reservoir, and Tringford pumping station (sited by Thomas Telford) worked the Startops End and Tringford reservoirs.  Each pumping station lifted water into the Arm to flow into the main line at Bulbourne Junction.  In his Encyclopædia of Civil Engineering (1847), Edward Cresy states that:

“. . . the principal engine at Tring is estimated as a 70 horse-power; its consumption of coals is about 1½ cwt. per hour, with a 40 feet lift; this engine works at a pressure of 24 pounds, makes ten strokes per minute, and pumps up sufficient for eighty locks in 24 hours.”

Writing some years ago, Tring local historian Bob Grace stated that:

“. . . the great reservoirs at Tring were not constructed in their present form in the first instance.  First of all they were just ‘heads’ - the Ashwell Head at Wilstone and the Bulbourne Head at Marsworth, which were dammed up and small pumping engines put in to pump direct into the Wendover navigable feeder, one pump being halfway between the main arm and New Mill and the other pump being at the White House, above Wilstone reservoir.  These were the first engines of the neighbourhood and the men who came to work them were, of course, engineers, the first to come into this part of the world.

The engines were vacuum engines, which meant that they worked on very little steam pressure (about 5 p.s.i., I think), from very simple boilers.  The engine was activated by the weight of the pump bucket drawing up the piston and the piston cylinder being filled with steam from this boiler, then a jet of water was squirted in condensing the steam.  The vacuum then formed drew up the bucket and brought up the water to the canal level.  These two engines were extremely inefficient, even by the standards of those days, and they were soon replaced by engines put in at the Tringford station.  These were two great beam engines.”

When Tringford pumping station was built in 1817, it was equipped with a Boulton and Watt beam engine of 80 locks per day capacity, so it is probably this engine that Cresy refers to.  However, in the period 1836-38, the Tring reservoirs were interconnected by a system of tunnels to enable all pumping to be centred on Tringford.  A second (second-hand) steam pump (capacity unknown) — named the ‘York’ — was then installed to handle the increased load, and this engine remained in operation until 1911 when it was replaced by diesel-electric plant.

Following the centralisation of pumping on Tringford, the pumping stations at Weston Turville and Whitehouses were demolished ― Marsworth pumping station had been dismantled in 1819, as this reservoir could then be pumped from Tringford through the new Startopsend reservoir.  Nothing remains of the pumping stations at Weston Turville and Marsworth, but some brick foundations and culverts on the canal bank mark the site of Whitehouses. [7]  In 1927, Tringford pumping station became wholly electrically-driven.  The original Bolton and Watt engine was then removed – it was offered for preservation, but in the absence of any takers it was sold for scrap – and the building greatly altered (and much for the worse!) including the removal of its prominent chimney.

Above: Tringford pumping station and stop lock, c. 1910.
Below: the beam of one of the station's steam pumping engines.

In 1870, the GJCC came into legal conflict with the Tring Local Board of Health over contamination of Tringford Reservoir and the spread of disease:

“Part of the drainage of this town [Tring] is carried away by a sewer which empties itself into the canal-reservoir to the north.  Before this sewer was made the reservoir received only spring-water, a matter of some importance, as some neighbouring villages drew their water from the stream that flows from the reservoir.  After the turning in of the sewer, in summer, when the water in the reservoir was low, it stank abominably; and worse, diphtheria, typhoid fever, and other such diseases, were frequent in the villages.”

The water supply of Buckinghamshire and of Hertfordshire by W. Whitaker (1921)

The GJCC sued for damages.  They complained of the pollution and of the additional expense incurred in pumping water up from Tringford reservoir that would otherwise have flowed directly into the Wendover Arm along Tring Brook.  However, the Master of the Rolls dismissed the case (with costs) on the grounds that the Board of Health were acting in the lawful exercise of their powers.  The following year, the GJCC mounted an appeal.  The Master of the Rolls had apparently misdirected himself, for according to The Times the GJCC were granted an injunction against the board of Health (with costs), the Lord Chancellor ruling that “the right of enjoyment of surface water in a flowing stream must not be interfered with” ― public health issues did not appear to enter into the argument!  Standards of public health have of course improved out of all measure since 1870, and today the summit pound obtains a useful supply of cleaned water from Tring sewage works, which is pumped into the Wendover Arm just to the east of Gamnel Bridge.

And where does the Wendover water released from the Tring Summit finish up?  That which flows southwards along the canal eventually reaches the Thames at Brentford.  That which flows down the sixteen locks of the Aylesbury Arm eventually enters the River Thame, discharging into the Thames in the vicinity of Dorchester (Oxfordshire).  Water that flows northward along the canal discharges over weirs into the Rivers Ouzel and Nene until at Cosgrove, where the canal commences its ascent towards Braunston Summit, it discharges into the Great Ouse, this flow eventually reaching the Wash.

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An outing to Wendover by members of the Akeman Street (Tring) Baptist Church in 1897.
Top:  approaching Little Tring. Bottom: at Hare Lane bridge (No. 8).


 
THE COMMERCIAL CANAL

IN addition to its role as a feeder for the Tring Summit, the Wendover Arm enjoyed a century of commercial life; indeed, on its eastern section, shipments of grain to Tring Flour Mill continued until the end of WWII, when road transport took over, while the adjacent Tring Dockyard survived until 1952.

Plan of the Feeder ditch as originally conceived.
The route that was to be followed at New Mill differs considerably from that eventually constructed.
Plan (jpeg, 3.3MB - back arrow to return)

Although originally planned as a feeder channel, at some stage during the land purchase negotiations the GJCC decided ― believed to have been in response to local lobbying ― to make the feeder navigable and thus revenue-earning.  Enlarging the feeder involved little extra cost, but its change of use did require a further Act of Parliament.  Thus, the following statutory notice appeared in the newspapers published along the line of the GJC, giving notice of the Company’s intention to apply to Parliament for an Act which, among other things, would authorise them:

 
“. . . . to make navigable, the cut or feeder now making, and intended to be made, by the company of Proprietors of the Grand Junction Canal, from the town of WENDOVER, in the said county of Buckinghamshire, to the summit-level of the Grand Junction Canal, at Bulbourne, in the parish of Tring, which is to pass in, to, or through the several parishes of Wendover, Halton, Weston-Turville, Aston-Clinton, Buckland, and Drayton-Beauchamp, in the said county of Buckingham; and the parish of Tring; till it joins the said summit-level at Bulbourne aforesaid.  Dated this 5th day of September, 1793.”

E. O. Gray, Aston Chaplin, Clerks to the Company

Reference to the “feeder now making” illustrates that construction of the Arm commenced at an early date, well before the main line reached Tring Summit (probably) early in 1799.  The new Act (34 Geo, III. C. 24) was obtained on 24th March, 1794, together with statutory authority to build branches to Buckingham, Aylesbury and Saint Albans (the latter not proceeded with).

Although the exact date of the Wendover Arm’s completion is unknown, it was probably during 1794, for in his progress report of May of that year, Jessop states that “About seven-eights of the Wendover Canal is cut”, and in a GJCC circular of November, 1797, reference is made to “The Wendover collateral line, now finished for the sake of the water”.  However, as the main line, which opened to Berkhamsted late in 1798, probably reached Tring Summit early in 1799, trade on the Arm would not have commenced until then.  The first clear intimation that the Arm was fully in business appears in Jackson’s Oxford Journal, which reported that the section of the GJC from Tring to Fenny Stratford was officially opened on 28th May, 1800.

For most of its working life the western section of the Arm avoided railway competition, and until the opening of the Aylesbury Arm (c. 1815), also carried traffic destined for Aylesbury:

“The Oxford canal, constructed under the superintendence of Brindley, was finished in 1790, and was opened with great rejoicings; it materially affected Aylesbury; coals and heavy goods were brought by it to within 25 miles of the town, the intervening distance being accomplished by road-waggons.  The main supply of coals for Aylesbury was then obtained from Oxford.  In the year 1799 the Wendover Branch of the Grand Junction Canal was completed, which was a great advantage to this district.  The traffic in coals and heavy goods was transferred from Oxford to Wendover Wharf, within five miles of Aylesbury.”

Buckinghamshire: A History of Aylesbury, Robert Gibbs (1885)

‘Wendover Band of Hope’ outing at Wendover Wharf, 1889.
The narrow boat owner is Alfred Payne of Wendover.

Wendover Wharf lies a short distance to the north of the town centre, [8] the original access being from the end of Clay Lane across grazing land belonging to Manor Farm.  In 1796, Wharf Road was built (at that time ending at Wendover Wharf) to give proper access to the Arm from Aylesbury Road.  Wharf Cottage, which still stands, was the wharfinger’s residence and warehouses (long gone) were built at the wharf opposite the tow path.  It is known that grain was landed there for milling at the great octagonal brick-built tower mill (now converted into a beautiful private dwelling) that stands on the opposite side of Aylesbury Road, perhaps including that referred to in the following report:

“Philip Goodenough was indicted for stealing four bushels of wheat, the property of Joseph Hoare.  The prisoner was the master of a barge . . . . in which a quantity of wheat was sent from London to Wendover, consigned to Mr. Hoare . . . when this wheat arrived at Wendover, four bushels of it were found missing.  The only evidence against the prisoner was that of a lad, named Merchant, who had acted as his servant in the barge. He said, that after the barge had passed Chelsea bridge, the prisoner took a spare sack and filled it, by taking a small quantity from each of the other sacks that were full; when the barge arrived at a place called Harwood, on the Grand Junction Canal, a man came up and took this sack so filled from the prisoner.”

The Times, 15th January, 1801.

Shrinkage of the sort described must have been common ― it certainly was with coal.  Hay and straw were also brought to the wharf from the surrounding fields and shipped to London, and manure was received in return.  Slater’s Directory for 1852 lists several coal merchants at the wharf; indeed, a correspondent writing in the Bucks Herald in 1906 had this to say about the Wharf’s coal trade: “Fifty or 60 years ago [c. 1850] waggons from places as far off as Lewknor and Aston Rowant were to be seen en route through Bledlow all the way to Wendover Wharf, for coal brought there by canal”.  The wharfinger at that time was John Bell, who offered water conveyance “To London and forward, goods to most parts of the kingdom”.
 

There were a number of other wharfs on the Arm (App. I.), the main ones being at Gamnel (also known as Tring Wharf) and at Buckland to the south of Aston Clinton.  A trade directory listing of 1854 suggests that Buckland wharf was managed by the landlord of the adjacent New Inn, whose other listed activities were “coal merchant and collector of taxes”.
 

A pair of Alfred Payne (Wendover) narrow boats at Buckland.
The New Inn is in the background, Buckland Gas Works was opposite the narrow boats.

The site of Gamnel Wharf had previously been occupied by a water mill that had been bought for its supply of water and dismantled by the GJCC. The first reference to the Wharf itself occurs in the GJCC Minutes. On 14th October 1800, a wharf at Tring (presumably Gamnel Wharf) was auctioned for three years from 29th September. It was taken by James Tate, a coal merchant, for £15 per annum (the Company Minutes for this period also record that the fishing rights for most of the Wendover Arm were let in June 1800 to Acton Chaplain, the GJCC’s Clerk, for twenty one years, at £2 10s a mile).  A deed of transfer records that on 5th July, 1810, the GJCC sold to William Grover, for £400, “all that wharf land and buildings thereon containing one acre and three roods more or less situate next Gamnel Bridge in the Parish of Tring.”  Grover must have seen a business opportunity to continue the milling previously done on the site, but by wind power; the tower mill that he erected at Gamnel became the seed from which eventually grew Heygates Mill, the large flour-milling complex that occupies the site today.
 

Gamnel Wharf windmill ( built c. 1812, pulled down in 1911) and steam mill (built 1875) ― note the lightening boat in the foreground.

Mr. & Mrs. Ward, daughter Phoebe and her family from Startops End,
discharging Manitoba wheat at Tring Flour Mills c. 1930s.

The 50th birthday celebration for William Mead (owner of Tring Flour Mills - background) in 1918, during which
he entertained wounded soldiers and airmen from RAF Halton Camp hospital, near Wendover.
The narrow boat Victoria is registered to Frederick Mead of Paddington.

Grover was also active as a canal carrier, his listing in Pigot’s trade directory for 1839 advertising “To London and all places on the line of the Grand Junction Canal, and goods forwarded to all other parts of the Kingdom, by Grover and Son, from Gamnel wharf, and Thomas Landon, from Cow Roast wharf, daily”.  Nothing then is known of Gamnel Wharf until the business changed hands in January 1843, when the following notice appeared in the Bucks Advertiser:

“William Grover, in the town of Tring in the County of Hertfordshire, having on the 28th day of January last disposed of the business of wharfinger, coal and coke merchant and mealman, and dealer in hay, straw, ashes, and other things, lately carried on by him in partnership with Thomas Grover, at Tring Wharf, and at Paddington in the County of Middlesex, under the firm of ‘WILLIAM GROVER & SON’ to his sons-in-law, William Mead and Richard Bailey.

Messrs. Mead and Bailey beg to announce that they will continue to carry on the same business, upon the said premises, in partnership under the name of ‘MEAD & BAILEY’. All debts due to and owing from the said William Grover, will be received and paid by Mead & Bailey.”

Bucks Advertiser, January 1843.

The notice gives a good indication of the nature of the business carried out, not just at Gamnel Wharf, but at Wendover and at many wharfs in rural locations at that time.
 

Mead and Bailey continued to offer a diverse range of services, later advertising themselves as millers, coal merchants, wharfingers, and water carriers. [9]  A few years later the partners advertised London horse manure (mountains of it were generated in the horse-powered Metropolis of that age), which they shipped by canal from their wharfs at Paddington.  Paddington Basin was also the scene of another William Mead & Co. activity, that of transporting by canal London’s rubbish for disposal in worked-out gravel and sand pits, and at nearby brick-yards (which recycled the cinders) ― a magazine article (App. II.) written in 1879 describes both the early use of electric light for illuminating the refuse wharfs and the unsavoury nature of Mead’s rubbish disposal business.  Shipments of imported grain were also delivered to Mead’s flour mill at Tring by canal from the London docks via Brentford, where the grain was transhipped from lighters to narrow boats for its journey up the GJC.  Grain shipments to the mill continued until the end of World War II, when road haulage took over.

In addition to the commercial wharfs on the Arm, there were two small canal-side gas works, which supplied town gas to the Rothschild mansions at Aston Clinton and at Halton.  Wendover Gas, Coke & Light Company was also located near the Wendover canal wharf.  The close proximity of these plants to the Arm suggests that they received supplies of coal by narrow boat and might also have exported the by-products of the town gas manufacturing process (coke, coal tar, sulphur and ammonia) by this means.
 
The last business to use the Arm was Bushell Brothers, a firm that over the years built and repaired a wide range of craft including canal barges of various types, pleasure boats, maintenance flats, tugs and a pair of fire floats for John Dickinson’s paper mills.  The firm ceased trading when the brothers retired in 1952, although by then the boat trade had diminished and the firm were building bodies for a range of commercial motor vehicles.
 

Bushell Bros. boatyard (Tring Dockyard) ― Tring Flour Mill to the rear.
Reproduced by kind permission of Miss Catherine Bushell.



Tug ‘Bess’ under construction at Tring Dockyard, 1921.
At 75ft x 14ft 6ins x 5ft 6ins draught, her size was such she could only just pass along the Canal to London.
Reproduced by kind permission of Miss Catherine Bushell.



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Sunday school outing about to depart from Gamnel Wharf, 1931.
Reproduced by kind permission of Miss Catherine Bushell.

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LEAKAGE AND PARTIAL CLOSURE

CONSTRUCTION of the Wendover Arm started soon after the 1793 Act had been obtained, for in a report submitted in May 1794, Jessop informs the Board that the Arm was almost complete, but not yet flooded.  From the outset it appears that he knew that the chalk terrain over which part of the Arm was to pass would prove difficult and that leakage might be a problem:

“About seven-eights of the Wendover Canal is cut, — the remainder having corn on the ground, will rest till after harvest; in the mean time what is done will be gradually tried with Water, for much of the ground in this line is very leaky, and must be lined with Earth, and be saturated with muddy Water: the rule that has been generally observed — of avoiding plain cutting until necessity calls for it, has a reasonable exception in this case, for by exposing it to the changes of Weather, and particularly to Frost, the Chalk will dissolve into a pulpy substance, and facilitate the operation of Puddling.”

William Jessop, London, 27th May 1794.

The first reported leakage was in 1802, and in the following year the Arm was closed for some months for remedial work.  This was carried out under the supervision of the canal engineer Benjamin Bevan, who during the project procured more water for the Arm at Wendover (App. III.) and submitted his proposal for what was to become Marsworth Reservoir.  When the civil engineer Thomas Telford inspected the GJC in 1805, his report picked up on Jessop’s concern, expressed a decade earlier, about leakage on the Arm:

“A great proportion of the Wendover Branch is cut through loose chalk; and Mr. Bevan appears to have laboured with much activity and zeal to render the whole watertight: in this he has partly succeeded; but much perseverance is requisite to make this important part of the canal perfectly secure; the lining with clay must be continued, and the banks must, in several instance, be made stronger and higher.  As much depends upon the perfection of this summit I cannot help strongly recommending that every attention be paid to it.”

Report on the General State of the Grand Junction Canal, Thomas Telford, May 1805.

Further problems with leakage occurred for the remainder of the Arm’s working life, the costs of significant repairs being announced periodically in newspaper reports of the Company’s Annual General Meetings.  In 1855, the Arm was closed due to leakage, but on this occasion repair was effected using a new form of lining, asphalt, in place of the traditional puddle clay.  This was applied to the section of the Canal between Little Tring and Aston Clinton and although it stemmed the leakage to some extent, it became damaged by a combination of earth movement, by canal boats brushing against it and through the use of poles. (App. IV.)  By 1897, the leakage had reached such an extent that the Arm was drawing water from the main line.  This led to the Canal being dammed at Little Tring, where much of the stop lock (built c. 1901) remains.

A number of schemes were then considered for restoring navigation or, as an alternative, reverting the Arm to its original role as a feeder.  With the arrival of the Metropolitan Railway at Wendover in September, 1892, the commercial future of the Arm must have looked bleak, added to which the numerous attempts to stop leakage over the years had proved expensive and unsuccessful.  These factors probably influenced the GJCC’s decision to abandon the Arm as a navigable waterway west of Little Tring.  However, the closure was contested in the High Court, where their Lordships, sitting as the Railway and Canal Commission, ruled unanimously in favour of the GJCC, the gist of their argument being that the Company was under no legal obligation to maintain the Arm as a navigable waterway, and at any rate the economics of so doing would have been prohibitive (the legal costs of the case would probably have paid for the Arm to be repaired!).

The report of the case (brought by Lord Rothschild, Lady de Rothschild and Mr Alfred de Rothschild) in The Times also provides some interesting information on the level of traffic on the Arm during its final years of commercial operation:

“The earning, which at one period yielded a good profit, had been on the decline for some time before 1898.  In 1883, the number of tons carried was 12,800, but the tonnage fell to 4,800 tons in 1893, 2,600 in 1894, and to less than 2,000 in 1896-7; and the decrease in the receipts from tolls was from £1,100 in 1883 to £423 in 1893, and to about £200 between 1893 and 1898.  One reason of the traffic falling off was in 1894 the Metropolitan Railway was opened to Wendover [reported elsewhere as Sept., 1892], and from that time the Wendover traffic in coals was transferred from the canal to the railway.  On the other hand it is estimated that the sum, that would have been expended on the part of the canal at present closed, before it could again be used as a navigable cut, would not be less than £22,000.  The ground on which the canal is constructed is chalk, and the necessity of preventing the loss of water from the porousness of the chalk accounts for a large part of the £22,000.”

Rothschild and others vs. the GJCC, The Times, 9th May, 1904.

The Arm was finally abandoned as a navigable waterway west of Little Tring in 1904, although for some years before (probably since at least 1897) it had only been in intermittent use.  However, as late as 1906, an appeal (typical of those that were to arise during the branch-line closures of the Beeching era) was made to the newly-convened Royal Commission on Canals to bring pressure on the GJCC to reopen the Arm to navigation:

“. . . . With capable handling, however, the Canal could be made to hold water effectively, and at no unreasonable cost.  The following figures represent part of the traffic in the year 1897, immediately before the canal was closed:

Manure ― 500 tons were sent to Wendover, and 120 tons to Buckland Wharf;
Hay and straw ― 350 tons were sent from Wendover, and 150 tons from Buckland Wharf.

This represents part of the traffic when the Canal was only half full of water, and boats had a difficulty in getting along partially laden . . . . In many ways those living in the parts of the counties served by the two branches are injuriously affected.  By increased cost of carriage of goods, equal to 2s. per ton to the nearest railway Station.  By inability to obtain manure for farmers at a reasonable cost.  By wear and tear of roads through having to cart goods and coal which ought to come by water.  By having to cart hay, straw and cereals to the Railway Stations, which represents 2s. in the ton extra cost to the farmers, and a reduced rental to the landowners, besides extra rates to the general public to cover wear and tear on the roads . . . .”

Bucks Herald, 2nd November, 1906.

It is interesting to note the Arm’s importance to its local farming community.  Reference to it being “half full of water” refers to the use of stop planks to block off the Arm prior to construction of the Little Tring stop lock (c. 1901).  It appears that, as early as 1891, boats navigating the Arm to the west of Little Tring had first to be lightened to reduce their draft on account of its shallow water:

“The Clerk [to the Council] had also received a letter from Mr Thomas Mead, of the [Tring] Flour Mills, complaining that boats bearing dung [were] lightening their loads (for the purpose of entering the shallow water of the Wendover Arm) near their mills, and he wished the practice, if the matter came under the jurisdiction of the Board, to be stopped. ― Mr Clarke corroborated the facts of the complaint. ― Mr Baines [the Council’s surveyor] said that he had been to the spot, and told the boatmen that the practice must be stopped, and that they must lighten elsewhere.  They asked him to allow them to lighten in the middle of the night, and he gave permission for this to be done.”

Bucks Herald, 4th July, 1891.

Following closure, the section between Wendover and Drayton Beauchamp was relined, the water level lowered and the flow from Wendover diverted into Wilstone Reservoir.  This scheme was later changed, the water being channelled from Drayton Beauchamp direct to Tringford pumping station through a pipeline laid along the canal bed.

The much disfigured Tringford pumping station in the late 1960s ― the Arm was then being used as a
dump for redundant narrow boats.  Note the condition of the tow path!

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RESTORATION

THE formidable project of restoring the Wendover Arm to a navigable waterway beyond Little Tring is being undertaken by members of the Wendover Arm Trust.  The Trust is a charitable body formed in 1989 with the aim of restoring and promoting the Canal.  Its membership ranges from organisations with a specific interest (such as the environment) to individuals who support the aims of restoration in general.  The Trust does not own the Canal; it is owned by The Waterways Trust, who work closely with the Trust on planning and undertaking its restoration, and are represented on the Trust’s Board.

The engineering problems in restoring the Arm are believed to be relatively straightforward, although the solutions are expected to be expensive, with funding being a major obstacle.  At the time of writing, progress has been slow but significant.

Although some work had been completed earlier, the first phase of the planned restoration was completed in March 2005.  It comprised the refurbishment of the stop lock at Little Tring; the replacement of a road embankment across the canal bed at Little Tring with a concrete road bridge, built to a traditional design and faced with bricks to provide an authentic appearance; construction of a winding basin at the terminus to allow boats to turn; and the reinstatement of about ¼ mile of canal.

The second phase (expected completion in 2016) involves restoring to navigation the section between Little Tring and an isolated section of restored and re-watered canal to the west of Drayton Beauchamp.  The latter was constructed during the building of the Aston Clinton Bypass in 2003, [10] and involved a slight realignment of the Arm to provide navigable headroom under the new bypass road bridge.  Restoring the phase 2 section includes re-profiling the Canal to its original shape and lining its sloping sides with concrete blocks on top of waterproof Bentomat© lining [11].  Two new timber footbridges have already been erected to enable the Canal to be crossed safely, and reinforced concrete covers are being laid over the 100-year old buried pipeline to prevent any subsidence should it collapse.
 

Relining the Wendover Arm - the upper part of the Bentomat liner, visible above the protective blocks,
is about to be covered with turf.
At the canal bed, the liner is covered with 300mm of earth.

The main obstructions to be met during Phase 3 concern bridge restrictions, these being the accommodation bridge at Buckland Wharf, the ex-A41 road bridge and the lowered Halton Village Bridge.  The restoration of this section is technically feasible but expensive.

――――♦――――

 
RECREATION, SPORT ― AND ALGAE

ANY large expanse of water holds a certain fascination and from their early days the Tring Reservoirs have been sites of recreation.  Walking and fishing provide much enjoyment, but at the head of the list must come interest in wildlife.  In recognition of this, the reservoirs were designated a National Nature Reserve in 1955; in 1987, they were redesignated a Site of Special Scientific Interest on account of their wealth of wildlife, particularly birdlife.  Because there are few natural lakes in Southern England, the reservoirs provide an important haven for wintering water birds.

Weston Turville Reservoir is outside this group.  Although it continues to be owned by The Waterways Trust, it is no longer used to supply canal water.  Managed by the Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust, it too is recognised as an important nature reserve while at the same time providing an expanse of water for the enjoyment of members of the Aylesbury Sailing Club, a nice mix of uses.
 

Lord Rothschild and party duck shooting on one of the canal reservoirs, 1921.

Somewhat at odds with the above, for 130 years the sporting rights to the reservoirs were retained by the landowners of the Tring Park Estate, who arranged shooting parties for their distinguished guests, which included on one notable occasion King Edward VII.  Until recent times the owners were entitled to shoot on up to six days per year, their quarry being captive-bred mallards reared on Marsworth reservoir and the smallest of the reservoirs at Wilstone.  A gamekeeper employed by the Estate also managed the three reservoirs stocked with coarse fish and the fourth with trout.  From April 2008 British Waterways acquired both the fishing and shooting rights, of which the latter has now been discontinued.

As for swimming, during the first decades of the 20thC this was a popular pastime and organised swimming galas were a regular fixture.  They were probably supervised and safe enough, but the general practice was eventually banned due to several fatalities caused by swimmers becoming entangled in water weed.
 

Swimming lessons, Wilstone Reservoir in the 1930s.

Prolonged dry spells, when the water levels fall drastically, cause deep cracks in the reservoir beds and the growth of a toxic phenomenon, Blue-green Algae (Cyanobacteria).  These algae grow so rapidly they are difficult to control and can produce toxins that are dangerous to humans as well as to animals and marine life in general.  Although susceptible to herbicides, the problem can also be addressed with the use of barley straw, which, in a complex chemical action, inhibits their spread.  Each of the reservoirs except Tringford, which is not affected, is now strung with lines to which barley-straw mattresses are attached.

――――♦――――

 
APPENDIX I.

THE WHARVES.

TODAY it is difficult to imagine that during the canal carrying era ― and particularly before the onslaught of the railways (c. 1840s) wiped out many of our canals (vide, for example, the fates of the Kennet & Avon and the Thames & Severn canals) ― these waterways were the trunk roads, even the motorways of their day.  Communities who were lucky enough to live near a canal route saw the prices of coal, timber, building materials and even food fall dramatically when the canal came to town.  Those in rural areas especially found a cheaper and quicker route to market for their farm produce; there is much evidence, for example, that the Wendover Arm was used to export hay and straw to the horse-powered Metropolis, where it was converted into horse dung (manure) and shipped back by canal for use as an agricultural fertiliser.  Although it was never particularly common, even humans travelled by canal:

Passengers by canal on the Paddington branch of the GJC.

It is recorded that the poor left Aylesbury by barge on the first stage of their journey in search of a better life in the colonies or the New World, while newspaper reports of troop movements by canal were quite common before the railway age:

The Morning Post, 5th December, 1821

Indeed,  the military even constructed a large barracks and arsenal adjacent to the GJC at Weedon, and into which Barnes built a short branch canal that entered the walled site through a portcullis.

Much cargo-handling on the Wendover Arm was probably carried out by boatmen drawing up their craft adjacent to a farmer’s field, and loading/discharging over planks between the boat and the bank. Where an accommodation bridge was conveniently placed, it would probably have been easier to moor under the bridge and transfer goods over the parapet.  But there is archaeological evidence of other wharfs on the Arm in addition to those generally known about.  Research carried out by Barry Martin suggests there were wharfs of some type at the following locations (moving upstream from Bulbourne Junction):

•      on the right (non-towpath side), a few hundred yards above the overspill weir, was the wharf edging for the Marsworth Engine/Pump;

•     on the left bank just before Gamnel Bridge (bridge 2) there is evidence of a wharf;

•     above Gamnel Bridge wharves associated with the various mills and the boatyard;

•     further upstream, beyond the Tring Feeder, there was a small wharf on the off-side, its edging being visible during wintertime when the foliage recedes. Local recollection is that it was a coal wharf;

•     the wharf edging associated with bringing coal supplies to the Tringford pumping station remains in place;

•     the next definite wharf edging was for the Wilstone (Whitehouses) pumping station;

•     just before Drayton Bridge (bridge 5) there was a brick wharf, on the off-side, adjoining Bridge Farm. This was certainly very evident when the first undergrowth clearance was done in about 1977, but when BW restored this section of canal the wharf was demolished;

•     next upstream was the wharf behind the New Inn, then beyond bridge 6 (the old A41) there was the wharfage for the Buckland Gas Works;

•     upstream of the Stable Lane (Wellonhead) Bridge (bridge 7) there was a further slewing bridge which provided access from the Aston Clinton House to the towpath side; although this is the site of the “concreted narrows”, a brick-fronted wharf was visible a few years ago;

•     if there were wharves at Halton, in the area of the now lowered road bridge, they would have disappeared during the construction of that bridge;

•     on the off-side, about 200 yards further on, there is another small brick-fronted wharf which may have been associated with the Dashwood estate. An old map (see fig. ‘5’ at Halton) of the area shows that the Canal was widened locally and there was a boathouse;

•     just before Perch Bridge, the Halton Gasworks would have had a wharf on the off-side.  Working boats were also known to have moored upstream of Perch Bridge (out of site of Sir John’s residence) and their crews visited the nearby Perch Inn, but there  probably wasn’t a wharf at this location.

•     the final wharf was probably that at Wendover, of which very little remains today other than the name, Wharf Road, and the wharfinger’s house.

――――♦――――

 
APPENDIX II.

FILTHY LUCRE

From GOOD WORDS
(Volume 20, 1879)
by
CHARLES CAMDEN.

I HAVE chosen my title with reference to the nature of the materials from which the gain of which I have to speak is extracted — very fertile “farms of two acres,” some of our dingy dust yards prove — not with the slightest to the character of the extractors. Through the courtesy of Messrs. W. Mead and Co, I have been allowed to pay a visit or two to a “contractor’s yard,” which claims to be the largest, at any rate to do the largest business, in London.  It is one of several bordering the Paddington Basin, which from that circumstance might be called, by a trade pun, a “slop” basin.

Most of the London dust-yards are at the water-side, for the sake of the water carriage which the canal or river gives them for their dust and cinders to the country brick makers.

In Messrs. Mead and Co.’s yard, the electric light is used after dusk in winter, to enable the men to go on with the loading of the barges.  Wandering along the muddy North Wharf Road, with its dozens of empty tumbrils resting with their shafts up in the air, or crossing the canal and railway bridges in Bishop’s Road, you catch sight of an aurora in the sky, and on entering the yard you see a big meteor star, pulsing white and bluish white, suspended in solitary brightness over the black heaps from which the weary sifters have gone home to rest, weirdly lighting up the men plying pick and shovel down by the canal, and making part of the sluggish water seem to be phosphorescently afire.  As far at the influence of the light extends, the separate stones can be distinguished on the gravel wharf, and within that circle the lamp-posts and the buildings of the yard stand out clear as by daylight, or rather clearer, since the mysterious brilliance seems to purge them of their grime.  But all gas-jets are turned into mere faint bilious blotches and outside the magic circle the darkness, both on land and water, is intensified into ebon gloom.

And now for the daylight aspect of the yard, or rather yards.  An apology for untidiness on a contractor’s premises has a somewhat droll sound, but one is made for the “muddle” in which the “slop-yard” is found.  The slop is just thawing after long frost.  A wide mass of dark, very unappetising batter-pudding is pent up on the wharf, waiting for a barge to come alongside; when a trap will be opened and the unsavoury mess cascade in a mudfall.  This accumulation of scavenging is indiscriminately called slop, but formerly street dirt dirt used to be divided into mud and “mac,” the latter being the product of traffic friction on macadamised roads, and the more valuable for builders purposes because freer from manure than mud.  When I asked my obliging guide at what rate the yard sold its slop, I was astonished to hear, “We get nothing, give it away to brick-makers fifteen or sixteen miles down the canal.  Yes, the cost of the carriage falls on us too.  We own twenty barges, with two men and a horse apiece, and we hire as well.  The brick-makers know that we must get rid of the slop, and so they won’t give us anything for it.  If” he added, “the yard were close to a country district, so that farmers could come with their carts, they would be glad enough to pay us for it, it makes excellent manure.”

Separate from the slop wharf by the gravel wharf, which, from its contrast to its neighbours on both sides looks strangely clean and almost goldenly bright, is the dust-yard.  Outside the gates empty dust and mud carts, so thickly furred with mud and dust that the owners’ names are often almost illegible, are congregated in the manner I have described.  Other carts are rolling out empty and rolling in full.  One of them unfortunately goes over a poor follow, who is taken up tenderly by two brother dusties and lifted with care into a cab, backed into the yard to receive him, and in this he is carried off to hospital in charge of a clerk.

The firm owns a hundred and twenty horses, manifestly well fed, and they are well housed also.  In their stables under the granary which contains their hay, straw, chaff, and crushed oats, hot as well as cold water is laid on for use at night.  Their drivers look as if they would be all the better for similar accommodation.  The dust that thickly covers the tracks in the yard is much like that one flounders through in iron-works.  Here the foot sinks over the ankle in dry, black powder, and there sticks fast in viscous, blacking-like mud.  Even on a winter afternoon, with the mercury dropping to freezing point, the perfumes floating, or, rather brooding in the atmosphere are not those of Araby the Blest.  On a sweltering summer day, after a shower, what must be the odours steaming up from such a conglomeration of ashes, egg-shells, oyster-shells, herring-heads, greasy rags and bones, old boots and shoes, and miscellaneous rubbish!  And yet the people employed in the yard, both men and women — so far as their flesh can be made out through the dirt with which they have peppered and besmeared it — look healthy, some quite plump and ruddy; and the same may be said of the men who go out with the dust carts and the scavengers.
 

Paddington Basin today.

――――♦――――

 
APPENDIX III.

OBTAINING A WATER SUPPLY FROM WENDOVER

(From “On the Utility, Structure and Management of Canals” by Joseph Townsend: published in
The Universal Magazine of Knowledge and Pleasure, Vol. XX, July-Dec 1813.)

MOST canals are distressed for want of water, because either they are above the springs, or they are not permitted to derive a supply from mill streams.  A knowledge of geology will, in most situations, relieve the engineer from distress, and teach him distinctly to what distance he must drive a level, or to what depth he must sink his shaft, that he may find ample supplies of water, such as no one can claim, because they nowhere break out in springs, till they issue either into the narrow seas, at the bottom of the ocean, or in the great abyss. . . .

It was this knowledge, derived from Wm. Smith, which enabled Mr. Bevan to direct his shaft into the chalk hills at Tring, by which he secured a supply of water for the Grand Junction Canal. . . .

In Dr. Rees’s New Cyclopedia we have a very interesting account of the manner in which Mr. Bevan supplied a part of the Grand Junction Canal with water.  This ingenious artist discovered, that on the north side of the chalk summit between Tring and Wendover, different water-tight beds in the lower chalk held up springs a considerable height above the canal, and, in order to avail himself of these, he began a tunnel in the upper bank of the canal near Wendover, which he drove half a mile southward to intercept the springs in their descent.  But observing that the principal of this water was in the winter and spring months, when the other sources were more than sufficient for the supply of the canal, he placed a strong water-tight valve in the most favourable part of his tunnel, which as soon in the autumn as the canal is amply supplied from its other feeds, he keeps shut until these begin to slacken in their supply.

The water in the immense planes of these beds of chalk accumulate, as in a vast subterranean reservoir, the springs rise to the level to which they originally rose, before this tunnel was begun, that is, twenty feet above the canal, and for many weeks after the opening of the valve in the beginning of summer they pour forth a most surprising stream of water into the canal, which otherwise would have found a vent miles off in the chalk vallies, or have slowly made its way down through the joints and fissures in the strata, to springs which issue at the bottom of the chalk below the level of the canal.

Had the Grand Junction, like the Kennet and Avon canal, been cut to the south-east of the chalk hills instead of being on the north side, as it is near Wendover, and had this canal been formed in a bed consisting of chalk rubble and of flinty gravel, Mr. Bevan would have had no need of penning up his chalk feeders in the autumn, in the winter, and in the spring.  Of this we can have no doubt, when we take a view of that immense quantity of water, which flows in the thick bed of gravel, far beneath the surface, all the way down the valley from Crofton, Bedwin, and Hungerford, to Kintbury, Newbury, and Reading.

――――♦――――

 
APPENDIX IV.

 THE CAUSES OF LEAKAGE AND THE ASPHALT LINING

The following text draws on research undertaken by Barry Martin and Professor Timothy Peters
 

THE Wendover Arm and the Llangollen Canal were the only significant canals built with the primary purpose of supplying water, in the case of the latter, to the central section of the Ellesmere Canal.  It is coincidental that they are also the only known canals where asphalt lining was used, although in the case of the Llangollen Canal it was only to effect a small repair.

From the outset if was realised that the ground over which the Wendover Arm was built would prove troublesome and, as outlined above, leakage soon became a problem that was to prove intractable in the long term.  There were probably two reasons for it:

• the porous nature of the ground through which the Arm was cut meant that it had to be lined, and there is evidence to suggest that this was not done properly.  The original puddle clay was sub-standard, having been excavated during the construction of Tring Cutting and used because it was cheap and readily available.  Commercial pressure to keep the Arm open left insufficient time for relining to be completed properly, while recent analysis of the asphalt lining put down in 1856-7 revealed it was poorly laid and not to the specified thickness;

• probably a more important reason is that the canal bed was roughly on the level of several ‘seasonal springs’, which from time to time punctured its lining.  With the low rainfall experienced in recent years it is now believed that the water table has fallen considerably and that this problem ought not affect the restoration work now being carried out.

In 1856, the Wendover Arm was again losing water and John Lake, the GJCC’s Engineer, visited some reservoirs (locations unknown) to inspect their use of asphalt as a liner.  His conclusion – supported by Sir William Cubitt, the Company’s consulting civil engineer – was that it would be far cheaper to repair the Arm using asphalt (£4,470) as against puddle clay (£12,500).  On this basis it was decided initially to apply a two inch thick lining of asphalt to the section of the Arm between Little Tring Bridge and the Wilstone Swing Bridge (¾mile ― the swing bridge has long since gone).

The asphalt mix that was used comprised one part of coal tar, one part of crushed limestone, one part of sand and some coal oil.  The sand was readily available from Leighton Buzzard, the limestone from local sources and John Bethell, owner of the Greenwich Gas Works (now the site of the Millennium Dome), was to supply 2,000 tons of coal tar at 10 shillings and 6 pence per ton, and 6,000 gallons of coal oil at 4 pence per gallon (records indicate that he was unable to supply more than 1,500 tons of coal tar, while other records show that considerable less actually arrived at Little Tring).

In June 1857, the Committee reported that the trial length of lining was satisfactory and that it should be extended further up-stream.  By the time the asphalting had reached Drayton Beauchamp, the mix had changed; the limestone had been replaced by crushed chalk and no coal oil was being used, while a recent analysis of a sample taken near Drayton Beauchamp revealed the presence of crushed coke (coke is a by-product in the production of town gas, and might have come from the nearby Buckland Gas Works).  On March 21st 1857, Sir William Cubitt tested and reported favourably on the quality of the asphalt.

In application, the asphalt was prepared in situ by crushing and mixing the ingredients, which were then heated in flat pans over braziers and poured and spread while still workable.  However, recent excavations have revealed that, in general, the applied thickness of the asphalt lining was one inch as opposed to the two inches specified, while it did not extend above normal water level on the canal banks!  Only a few small examples of asphalt lining have been discovered whose thickness exceed one inch – notably a nine inch thick section on the tow-path side of the canal bed near bridge No.4, which is thought might be a repair.  The GJCC Minutes record a quantity of surplus coal tar being sold off.

On May 13th 1858, Lake tested for leakage over a 3,828 yards section and recorded a rate of 1½ locks per day compared to 15 locks per day before relining.  GJCC records indicate that the asphalt repairs were initially considered successful, but after 12 years the Arm was again experiencing leakage, the integrity of the lining probably have being affected by several causes including an excessively rich lining mixture, poor construction practice, and damage from boats, ice breaking and earth movements.  Recent excavations have also revealed that the existing clay puddle was removed prior to the asphalt being laid, and that it received no protection afterwards (the current restoration practice includes putting down a considerable layer of earth ― 300 mm ― on top the Bentomat liner in the bed, concrete blocks over the lining on the banks up to water level, and turf above).
 

The former Whitehouses swing bridge c. 1896.
Reproduced by kind permission of Mike Bass.
Below, the same bridge after the Arm had been abandoned -
Marsworth Reservoir in the background.

――――♦――――

 
FOOTNOTES

James Barnes (c. 1739-1819); Civil Engineer.
Resident Engineer and Surveyor of the route of the GJC
and most of its branches.  He supervised the GJC’s construction.

William Jessop (1745-1814), a leading Civil Engineer of the era.
Chief Engineer and consultant to the GJC project.
 

2.

One example ― there were many others ― of drought bringing trade to a halt was reported in The Bucks Herald during October 1902.

In the Tring locality, water shortage has at times resulted in closure of the Aylesbury Arm, which places a drain on the main line.  When constructed, there was no need to line Tring Cutting, which was then below the water table, but the low rainfall in recent years has caused the water table to fall with the result that the Cutting now leaks, exacerbating the water shortage caused by drought.

3.

. . . . as did Robert Stephenson with the London & Birmingham Railway.  Other gaps in the Chilterns exist at Wendover and at Princes Risborough.

4.

Principally the Tring Feeder and the Tring Drainage, but there are other springs along the route, notably the Wendover Wides.  At Tring, outflows from the Miswell and Frogmore springs were merged to form the Feeder,  which, as an embanked brook, flows into the Wendover Arm at Gamnel.  The outflow from Dundale Spring flows beneath the Wendover Arm at Gamnel and into Tringford Reservoir, from where water is pumped back into the Arm at Tringford pumping station.

5.

At the First Committee Meeting of the GJCC (Wednesday, 5th June 1793), the Marquis of Buckingham agreed to sell his mill at Weston Turville for £400 and a second mill in Wendover for £1,750.  He also agreed to persuade his friend and local landowner, Sir John Dashwood King, (3rd Bt.), to sell the water rights for his mill at Halton and to consent for the feeder (as it then was) to pass through Halton Village.  Sir John’s mill was demolished.  Its millpond, situated upstream of Perch Bridge, became what is now referred to as the ‘larger wide’, the mill stream being diverted to flow as a feeder stream eastward towards Buckland.

6.

In 1800, the Blisworth Tunnel had still to be built.  Until this was completed in 1805, and the canal opened throughout, a temporary horse tramway was built to convey goods across the gap between Blisworth and Stoke Bruerne.

7.

At the time of writing, the Whitehouses site is being excavated by industrial archaeologists.

8.

During its construction, the townspeople petitioned to have the Arm extended into the town centre, but as the GJCC had what they required (i.e. a water supply) and would not have benefitted from the additional cost, this was declined.

9.

By the 1850s competition from rail transport was probably being felt, for the carrier service from Gamnel is shown as operating only three days a week.

10.

Building the new bypass had posed the risk of permanently severing the Arm.

11.

A synthetic impervious liner.  It is also self-sealing.  In the event that it is punctured locally by a sharp object, the bentonite it contains swells to plug the gaps, reinstating the impermeable liner.