b & b plymouth hoe Home Page Your Room Breakfasts Prices Finding Us Plymouth Exploring Booking Links Contact Us accommodation plymouth, plymouth hoe, coastal path holiday, bed & breakfast, guest house vacation, guesthouse, business accomodation, short break acomodation, b&b acommodation, devon hotel Plymouth Breakwater is a 1,560 metres (1,710 yd) stone breakwater protecting Plymouth Sound and the anchorages therein. It is 13 metres (43 ft) wide at the top and the base is 65 metres (213 ft). It lies in about 10 metres (33 ft) of water. Around 4 million tons of rock were used in its construction in 1812 at the then-colossal cost of £1.5 million (equivalent to £74.7 million today). In 1806, as the Napoleonic Wars impended, Lord St. Vincent commissioned John Rennie and Joseph Whidbey to plan a means of making Plymouth Bay a safe anchorage for the Channel Fleet. In 1811 came the order to begin construction; Whidbey was appointed Acting Superintending Engineer. This task required great engineering, organizational and political skills, as the many strictly technical challenges were complicated by the significant resources devoted to the project, from which various parties evidenced a desire for advantage. Nearly 4,000,000 (four million) tons of stone were quarried and transported, using about a dozen ships innovatively designed by the two engineers. A paper to the Royal Society suggests that Whidbey found many fossils as a result of the quarrying necessary to the breakwater. The foundation stone was laid on Shovel Rock August 8, 1812. It followed a line over Panther Rock, Shovel and St. Carlos Rocks, and was sufficiently completed by 1814 to shelter ships of the line. Napoleon was reported as commenting that the breakwater was a grand thing, as he passed by it on the way to exile on St. Helena in 1815. Severe storm damage in 1817 and 1824 prompted a change in the profile and height. Whidbey continued to work on the breakwater and other engineering projects, including the breakwater's lighthouse (designed by Walker & Burgess for Trinity House), until retirement around 1830. It was finished by 1841, the final work being finished by Rennie's son, Sir John Rennie. The lighthouse became operational in 1844, and soon afterwards a horse-drawn omnibus was driven from end to end, with a full compliment of passengers and accompanied by a military band. A beacon was placed at the eastern end, consisting of a 6 foot spherical cage on a 17 foot pole; the cage was designed as a refuge for six shipwrecked sailors In 1860, a Royal Commission established by Lord Palmerston, produced a plan for the defence of Plymouth and other Royal Dockyards. The Breakwater Fort was designed to defend the entrances to Plymouth Sound in conjunction with forts and batteries on either shore. Designed by Captain Siborne, work on the oval masonry sea fort started in 1861 and the main structure was completed in 1865. It has its foundations on Shovel Rock and is 35 yards inside the Breakwater. After several changes in plan, the fort was finally armed in 1879 with fourteen 12.5-inch and four 10-inch rifled muzzle-loading guns in armoured casemates. Although the fort had been disarmed before World War I, it served as a signal station, and from 1937, an anti-aircraft training school. It was finally released by the military in 1976. Offshore breakwaters, also called bulkheads, reduce the intensity of wave action in inshore waters and thereby reduce coastal erosion. They are constructed some distance away from the coast or built with one end linked to the coast. The breakwaters may be small structures, placed one to three hundred feet offshore in relatively shallow water, designed to protect a gently sloping beach. Breakwaters may be either fixed or floating: the choice depends on normal water depth and tidal range. Breakwater construction is usually parallel or perpendicular to the coast to maintain tranquility condition in the port. Most of Breakwater construction depends upon wave approach and considering some other environmental parameters When oncoming waves hit these breakwaters, their erosive power is concentrated on these structures some distance away from the coast. In this way, there is an area of slack water behind the breakwaters. Deposition occurring in these waters and beaches can be built up or extended in these waters. However, nearby unprotected sections of the beaches do not receive fresh supplies of sediments and may gradually shrink due to erosion, namely longshore drift. Breakwaters are subject to damage, and overtopping by big storms can lead to problems of drainage of water that gets behind them. The wall also serves to encourage erosion of beach deposits from the foot of the wall and can increase longshore sediment transport.
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