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26-533: The Stone Jetty is a jetty in Morecambe , Lancashire , England. It was built by the North Western Railway in 1853 as a wharf and rail terminal for both passenger and cargo transport. The former station building with adjoining lighthouse stand on the jetty and are Grade II-listed. The jetty was resurfaced and partly rebuilt in the 1990s as part of coastal defence works, which was combined with

52-402: A concrete foundation was raised 50 feet (15 m). above low water of neap tides . A small tidal rise spreading tidal water over a large expanse of lagoon or inland backwater causes the influx and efflux of the tide to maintain a deep channel through a narrows no longer confined by a bank on each side, becomes dispersed, and owing to the reduction of its scouring force, is no longer able at

78-621: A definite channel and protecting the mouth from being blocked up by littoral drift. This system was long ago applied to the shifting outlet of the river Yare to the south of Yarmouth , and has also been successfully employed for fixing the wandering mouth of the Adur near Shoreham , and of the Adour flowing into the Bay of Biscay below Bayonne. When a new channel was cut across the Hook of Holland to provide

104-417: A dock may be created by building enclosing harbour walls into an existing natural water space, or by excavation within what would otherwise be dry land. There are specific types of dock structures where the water level is controlled: Where the water level is not controlled berths may be: A dockyard (or shipyard) consists of one or more docks, usually with other structures. In American English , dock

130-411: A little above low water of neap tides , on which open timber-work is erected, provided with a planked platform at the top raised above the highest tides. In other cases, they consist entirely of solid material without timber-work. The channel between the jetties was originally maintained by tidal scour from low-lying areas close to the coast, and subsequently by the current from sluicing basins; but it

156-414: A moderate distance from the shore effectually to resist the action of tending to form a continuous beach in front of the outlet. Hence a bar is produced that diminishes the available depth in the approach channel. By carrying out a solid jetty over the bar, however on each side of the outlet, the tidal currents are concentrated in the channel across the bar, and lower it by scour. Thus the available depth of

182-430: A straighter and deeper outlet channel for the river Meuse , forming the approach channel to Rotterdam , low, broad, parallel jetties, composed of fascine mattresses weighted with stone, were carried across the foreshore into the sea on either side of the new mouth of the river, to protect the jetty channel from littoral drift, and cause the discharge of the river to maintain it out to deep water. The channel, also, beyond

208-408: A weak spot of the beach, which along a low coast may be at some distance off; and this new outlet in its turn may be blocked up, so that the river from time to time shifts the position of its mouth. This inconvenient cycle of changes may be stopped by fixing the outlet of the river at a suitable site, by carrying a jetty on each side of this outlet across the beach, thereby concentrating its discharge in

234-467: Is also commonly used to refer to wooden or metal structures that extend into the ocean from beaches and are used, for the most part, to accommodate fishing in the ocean without using a boat. In American English , the term for the water area between piers is slip . In the cottage country of Canada and the United States , a dock is a wooden platform built over water, with one end secured to

260-446: Is now often considerably deepened by sand-pump dredging . It is protected to some extent by the solid portion of the jetties from the inroad of sand from the adjacent beach, and from the levelling action of the waves; while the upper open portion serves to indicate the channel and to guide the vessels, if necessary (see harbor ). The bottom part of the older jetties, in such long-established jetty ports as Calais , Dunkirk and Ostend ,

286-460: Is technically synonymous with pier or wharf —any human-made structure in the water intended for people to be on. However, in modern use, pier is generally used to refer to structures originally intended for industrial use, such as seafood processing or shipping , and more recently for cruise ships , and dock is used for almost everything else, often with a qualifier, such as ferry dock , swimming dock, ore dock and others. However, pier

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312-466: The Gulf of Khambhat has the highest tidal amplitude and ships can be sluiced through flow tides in the river estuary . The engineers built a trapezoidal structure, with north–south arms of average 21.8 metres (71.5 ft), and east–west arms of 37 metres (121 ft). In British English , a dock is an enclosed area of water used for loading, unloading, building or repairing ships . Such

338-515: The Red Sea coast. Archaeologists also discovered anchors and storage jars near the site. A dock from Lothal in India dates from 2400 BC and was located away from the main current to avoid deposition of silt . Modern oceanographers have observed that the ancient Harappans must have possessed great knowledge relating to tides in order to build such a dock on the ever-shifting course of

364-464: The Sabarmati , as well as exemplary hydrography and maritime engineering . This is the earliest known dock found in the world equipped to berth and service ships. It is speculated that Lothal engineers studied tidal movements and their effects on brick-built structures, since the walls are of kiln -burnt bricks. This knowledge also enabled them to select Lothal's location in the first place, as

390-613: The approach channels to Venice through the Malamocco and Lido outlets from the Venetian Lagoon have been deepened several feet (metres) over their bars by jetties of rubble, carried out across the foreshore into deep water on both sides of the channel. Other examples are provided by the long jetties extended into the sea in front of the entrance to Charleston harbour, formerly constructed of fascines weighed down with stone and logs, but subsequently of rubble stone, and by

416-764: The handling of boats or ships (usually on or near a shore ). In British English , the term is not used the same way as in American English; it is used to mean the area of water that is next to or around a wharf or quay. The exact meaning varies among different variants of the English language . "Dock" may also refer to a dockyard (also known as a shipyard ) where the loading, unloading, building, or repairing of ships occurs. The earliest known docks were those discovered in Wadi al-Jarf , an ancient Egyptian harbor , of Pharaoh Khufu , dating from c.2500 BC located on

442-403: The influence of littoral currents, which, by conveying away some of the sediment, postpone the eventual formation of a fresh bar farther out (see river engineering ). Where a river is narrow near its mouth, has a generally feeble discharge and a small tidal range, the sea is liable on an exposed coast to block up its outlet during severe storms. The river is thus forced to seek another exit at

468-413: The installation of public art and sculptures. This Lancashire location article is a stub . You can help Misplaced Pages by expanding it . Jetty One form of jetties, wing dams , are extended out, opposite one another, from each bank of a river, at intervals, to contract a wide channel , and by concentration of the current to produce a deepening. Jetties have been constructed on each side of

494-465: The line of quays at the side, to enlarge the accommodation; and they also serve, when extended on a large scale from the coast of a tideless sea under shelter of an outlying breakwater, to form the basins in which vessels lie when discharging and taking in cargoes in such a port as Marseille . The approach channel to some ports situated on sandy coasts is guided and protected across the beach by parallel jetties. In some cases, these are made solid up to

520-454: The outlet river of some of the rivers flowing into the Baltic , with the objective of prolonging the scour of the river and protecting the channel from being shoaled by the littoral drift along the shore. Another application of parallel jetties is in lowering the bar in front of one of the mouths of a deltaic river flowing into a tide — a virtual prolongation of its less sea, by extending

546-405: The outlet of the river Nervion into the Bay of Biscay has been regulated by jetties; and by extending the south-west jetty out for nearly 0.5 miles (0.80 km) with a curve concave towards the channel the outlet has not only been protected to some extent from the easterly drift, but the bar in front has been lowered by the scour produced by the discharge of the river following the concave bend of

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572-674: The scour of the river out to the bar by banks. Jetties prolonging the Sulina branch of the Danube into the Black Sea , and the south pass of the Mississippi River into the Gulf of Mexico , formed of rubble stone and concrete blocks, and respectively, have enabled the discharge of these rivers to scour away the bars obstructing the access to them; and they have also carried the sediment-bearing waters sufficiently far out to come under

598-422: The slope for supporting coal-tips. Pilework jetties are also constructed in the water outside the entrances to docks on each side, so as to form an enlarging trumpet-shaped channel between the entrance, lock or tidal basin and the approach channel, in order to guide vessels in entering or leaving the docks. Solid jetties, moreover, lined with quay walls, are sometimes carried out into a wide dock, at right angles to

624-484: The southwest jetty. As the outer portion of this jetty was exposed to westerly storms from the Bay of Biscay before the outer harbour was constructed, it has been given the form and strength of a breakwater situated in shallow water. Where docks are given sloping sides, openwork timber jetties are generally carried across the slope, at the ends of which vessels can lie in deep water or more solid structures are erected over

650-481: The two converging rubble jetties carried out from each shore of Dublin Bay for deepening the approach to Dublin harbour. Jetties have the adverse effect of endangering Surf Culture as a whole with their ability to destroy surf breaks. Dock (maritime) The word dock (from Dutch dok ) in American English refers to one or a group of human-made structures that are involved in

676-438: Was composed of clay or rubble stone, covered on the top by fascine-work or pitching, but the deepening of the jetty channel by dredging and the need that arose for its enlargement led to the reconstruction of the jetties at these ports. The nes jetties at Dunkirk were founded in the sandy beach, by the aid of compressed air, at a depth of 22.75 feet (6.93 m). below low water of spring tides; and their solid masonry portion, on

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