The Grand Union (formerly the Grand Junction) canal, as its name implies, was designed to be part of a system of canals linking with each other rather than a single canal. Indeed, many waterways make up the integrated Grand Union Canal as it is today, forming a main artery to link the prime routes from London and the south to Birmingham and the Potteries.
The main line runs effectively from the River Thames at Brentford westward to Cowley Junction (access to the Slough Arm) then north and north west to the midlands.
With a wide variety of landscapes and numerous towns and historic canalside halts, the GU offers various options as the many arms which make up this wonderful waterway come and go at junctions like Bulls Bridge (Paddington Arm leading to the very heart of London), Marsworth (Aylesbury Arm), Gayton (Northampton Arm), Norton (Leicester Section), Braunston (Oxford Canal), Napton (Oxford Canal), Kingswood (Stratford on Avon Canal), and Bordesley where the Grand Union enters the Digbeth Branch and the Birmingham & Fazeley canal.
The Grand Union Canal ascends some 380 feet from its junction with the River Thames until, after a climb of 56 locks in over 36 miles, it reaches the two and a half mile long Tring Summit. Here the descent northwards towards Braunston commences.
The Tring Summit was completed in 1797, in advance of the main line to north and south. As this stretch of water was to supply the needs of the canal on both sides of the summit it became imperative to find sufficient water; the first Act of Parliament for the canal stated the need for a feeder from the north side of the Chiltern Hills behind Wendover to the summit level. The Wendover Arm became the first of several feeders to the summit level.
Work started on the construction of the Wendover Arm in the summer of 1793 and followed the 390 ft. contour line to join the summit of the Grand Junction Canal at Bulbourne Junction on the Tring summit level. After construction of the Arm had started, it was soon realised that little extra expense would be incurred in making the feeder navigable and authority to carry out this work, costing £13,000, was obtained in 1794. Although the Wendover Arm was primarily built to supply water for the locks at Marsworth and Cowroast it was served by many wharves along its length sending local produce to the London markets and also receiving coal, timber and manure for use on the land.
Commercial traffic on the Grand Junction Canal increased very rapidly - the canal was the "M1" of its day - so much so that a great number of reservoirs were built in the Tring area to collect water for canal use.
But the life of the Arm was short. By 1802 there was a considerable loss of water through the banks and the canal was closed for repairs to be carried out. By 1841, 20 locks of water were being lost per day through leakage, and extensive repuddling over a length of four and a half miles was carried out. To no avail, however, as by 1855 some 25 locks of water were escaping. Further repairs saw the lining of the leaking parts of the canal with a layer of asphalt two and a half inches thick, in preference to repuddling with clay, a task which was completed by 1858. In spite of this, by 1870 the loss was 30 locks of water per day. Repair work continued in 1895-96. In 1897 the leakage was so large that the Arm was actually taking water from the main line.
Trade was lost to the nearby Aylesbury Arm which did not suffer from the same problems. - this of course meant that the Wendover Arm became less commercially viable. Stop-planks were put in at Little Tring with the result that, although the Wendover Arm was severed, the level of water in the summit pound immediately improved. A stop-lock (which can still be seen above the Pumping Station) was constructed at Little Tring to permit the Arm to be used for traffic should the water situation improve. Eventually, despite massive protests from local people, the Royal Commission for Canals and Waterways, and the County Councils of Herts. and Bucks., the Grand Junction Canal Company blocked the canal above the stop lock and Little Tring, de-watered the next 1¼ miles and lowered the water level on the remaining 3¾ miles. The Arm was closed in 1904.
So that some of the water could still be carried an 18 inch pipe was built for 1¾ miles near Tring. The present situation is that the leaks are worse and the pipe is in urgent need of replacement. Because British Waterways must spend money to do those repairs the Trust is trying to get added funds from the Millenium Commission and other sources so they can take advantage of this one-off chance to restore the navigation. The work would be phased over several years so that wild life could migrate around the work in progress. Also the water flow would be maintained. British Waterways' Chris Mitchell said the repair work would soon become urgent as the pipe was in danger of collapse and the shallow, silted up canal prevented flood control measures with the result that the canal's neighbours in the nearby village of Drayton Beauchamp suffer flooding in the winter.
Despite the strenuous efforts of many organisations, trying to prevent further deterioration of the infrastructure, bridges were lowered, culverted or demolished.Finally at a meeting in October 1985, instigated by the Grand Union Canal Society, a steering committee was formed which became the Wendover Arm Trust.