Gloucester and Sharpness Canal

thumb|right|1933 map: the canal is the thin blue line from Gloucester (upper right) to Sharpness (lower left)

The Gloucester and Sharpness Canal (also known as the Gloucester and Berkeley Canal) is a ship canal in the west of England, between Gloucester and Sharpness, completed in 1827. For much of its length the canal runs close to the tidal River Severn, but it cuts off a long loop in the river at a once-dangerous bend near Arlingham. It was once the broadest and deepest canal in the world. The canal is long.

Canal planning and construction

thumb|right|alt=Founder's share of the Glocester and Berkeley Canal Company, issued 29 September 1794, printed on vellum. The proprietors of this canal were authorised to raise the sum of £140,000 to be divided into shares of £100 each. If the former sum be insufficient, then they raise a further sum of £60,000.|Founder's share of the Glocester and Berkeley Canal Company, issued 29 September 1794, printed on vellum. The proprietors of this canal were authorised to raise the sum of £140,000 to be divided into shares of £100 each. If the former sum be insufficient, they could raise a further sum of £60,000.

Conceived in the canal mania period of the late 18th century, the Gloucester and Berkeley Ship Canal scheme (as it was originally named) was started by architect and civil engineer Robert Mylne. An act of Parliament, the (33 Geo. 3. c. 97) was obtained, authorising the raising of a total of £200,000. The project rapidly encountered financial difficulties, to such an extent that Mylne left the project in 1798.

By mid-1799 costs had reached £112,000 but only of the canal had been completed. Mylne's role was taken over by James Dadford, who had originally been engaged as resident engineer on the project in 1795. Lack of funds resulted in the company ceasing to employ Dadford in 1800.

Eventual completion

Following the Public Works Loans Act 1817 (57 Geo. 3. c. 34), it was possible for the company to borrow money from the Exchequer Bill Loan Commission. This, along with further share issues, provided enough money to bring the scheme to completion. After these significant delays, the canal opened in April 1827. In the course of its construction the canal had cost £440,000 ().

Tracking

In the early years of the Canal, with the use of sails being prohibited or significantly limited, tracking (towing) of vessels was undertaken using horses provided by a succession of tracking agents appointed by the Canal Company. During May 1858, the Canal Company permitted the carrying company of Danks, Venn and Sanders to use their Stothert built screw tug Pioneer for tracking on the Canal. By November 1859 the Canal Company were undertaking their own trials using a rented tug (Reindeer, owned by J.M. Hyde of Bristol). This was successful, and shortly thereafter they ordered their tracking agent Timothy Hadley to place an order for two steam tugs; these were Moss Rose (1860) and Mayflower (1861) with a third (Violet, 1862) following on shortly after. The use of horses was significantly reduced as a result, and other tugs followed.

Eventual dividends

By the middle of the 19th century it proved possible to pay a small dividend, the debt to the Exchequer Bill Loan Commission having been repaid with the help of a loan of £60,000 from the Pelican Life Assurance Company.

Sharpness New Docks

A new, larger entrance and tidal basin at Sharpness was completed in 1874; during this year the Gloucester and Berkeley Canal Company acquired the Worcester and Birmingham Canal Company by the (37 & 38 Vict. c. clxxxi), and the tugs from Timothy Hadley. At this point, the canal company was renamed the Sharpness New Docks and Gloucester and Birmingham Navigation Company.

Where the Severn Railway Bridge (completed in 1879) passed over the canal, a swing section was constructed Barges, trows and schooners were "hulked" at high tide, and have since filled with silt. More boats have been added, including the schooner Katherine Ellen which was impounded in 1921 for running guns to the IRA, the Kennet barge Harriett, and ferrocement barges built in World War II.

In 1999, Paul Barnett started a privately funded research project to record the 81 vessels at the site, recognised as the largest ships' graveyard in mainland Britain. In 2010 British Waterways took control of the site in an attempt to protect it.

Bridge-houses

Eight of the bridges have Neo-classical bridge-men's houses in the near vicinity. These were built in the early 19th century when the volume of traffic on the canal made it important that all the bridges could open at night so that vessels could meet the tides at Sharpness. At that time, the other bridge-men lived in existing houses that were close enough to their bridges.

The classical-style bridge-men's houses were originally symmetrical in plan with gables on each elevation. Each had a living room, one bedroom, a scullery at the back and a porch with Doric columns at the front. In later years, the houses have been extended to provide more accommodation and modern facilities. Today, the houses are in private ownership, and most of them are Grade II listed.

File:Rea Bridge Bridgehouse.jpg|Rea Bridge Bridge-house

File:Sellars Bridge Bridgehouse.jpg|Sellars Bridge Bridge-house

File:Hardwicke Bridge Bridgehouse.jpg|Hardwicke Bridge (now removed) Bridge-house

File:Parkend Bridge Bridgehouse.jpg|Parkend Bridge Bridge-house

File:Fretherne Bridge Bridgehouse.jpg|Fretherne Bridge Bridge-house

File:Splatt Bridge Bridgehouse.jpg|Splatt Bridge Bridge-house

File:Cambridge_Arms_Bridge_Bridgehouse.jpg| Cambridge Arms Bridge Bridge-house

File:Purton Upper Bridge Bridgehouse.jpg| Purton Upper Bridge Bridge-house

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Modern times

In 1905 traffic exceeded one million tons for the first time. Oil was added to the list of cargoes carried by the canal, with bulk oil carriers taking fuel to storage tanks sited to the south of Gloucester. The canal was nationalized in 1948. At the same time the Sharpness Dock Police, which had policed the dock since 1874, were absorbed into the British Transport Police.

In 1955 the Board of Survey of Canals and Inland Waterways released a report that, among other things, described the Gloucester and Sharpness Canal as carrying substantial traffic and offering scope for commercial development.

The River Cam, which is subject to accretion due to industrial and agricultural runoff, is an important feeder for the Gloucester and Sharpness Canal. It was formerly navigable as the Cambridge Arm with one entrance lock leading to a basin and wharf at Cambridge, the limit of navigation due to mill weirs and low bridges on the Bristol to Gloucester road. The lock was missing and the basin abandoned by 1901. Most of the straightened channel has survived as flood defence measures and is potentially still navigable, but the entrance is now blocked by a low bridge at the site of the former lock.

By the mid-1980s commercial traffic had largely come to a halt, the canal being given over to pleasure cruisers with the exception of a few passages by grain barges. The oil trade ceased in 1985 with the closure of the petroleum depot at Quedgeley. To allow the A430 Gloucester southwestern bypass to be built, the canal had to be diverted. This new cut eliminated a major problem which had plagued commercial traffic since opening: the sharp double bend in the canal. The new section of channel was opened on 6 May 2006. In January 2009 a project began to replace the Patch Bridge swing bridge with a motor-powered design instead of the former hand-cranked system.

Today, the canal can be used by boats up to in length, in beam and in height. The maximum draft is .

File:Dutch Barge passing a swing bridge, on the Gloucester & Sharpness Canal.jpg|A motorised Dutch barge passing a swing bridge on the Gloucester & Sharpness Canal

File:Gloucester and Sharpness Canal at Patch Bridge.jpg|The canal at Patch Bridge, near the Wildfowl Reserve at Slimbridge

File:Berkeley.and.sharpness.canal.ts.jerwood.arp.jpg|The Sea Cadet training ship TS John Jerwood passes through Patch Bridge, on its way to the River Severn

File:Gloucester and Sharpness.JPG|The canal at Saul Junction

File:G&SCanal.JPG|The canal at the entrance to Gloucester docks