Dock

A dock is a man-made structure used to handle boats and ships.

These structures are typically located on or near a coastline. They serve many vital roles in maritime activities. People use docks to load or unload cargo from large vessels. They also provide spaces to build or repair ships. The specific meaning of the word can change based on language. In American English, a dock is often a structure for people to stand on.

In British English, the term often refers to the water area near a wharf or quay.

Some docks are designed to control water levels through specific mechanisms. A wet dock, also called an impounded dock, uses gates or a lock to manage water. This setup allows ships to remain afloat even when the tide goes down. The lock functions by maintaining a constant water level despite the rising or falling tide. This stability makes the transfer of cargo much easier for workers. Without these controls, ships might settle on the bottom during low tide. This would make loading and unloading very difficult.

There are several distinct types of docking structures used today. A dry dock is a basin that can be emptied of all its water. This process allows workers to inspect and maintain the underwater parts of a ship.

A floating dry dock is a submersible structure. It can lift a ship out of the water when no land-based facilities are available. In some areas, ships use NAABSA facilities. This stands for "Not Always Afloat But Safely Aground." Ships using these must be specifically designed to settle on the bottom at low tide. Other berths may simply be floating, where there is always enough water to keep the ship afloat.

Humans have been building docks for thousands of years. The earliest known docks were discovered in Wadi al-Jarf. This was an ancient Egyptian harbor used by Pharaoh Khufu around 2500 BC. Archaeologists found anchors and storage jars at this site. Another ancient example is found in Lothal, India, dating from 2400 BC. This dock is the earliest known structure equipped to berth and service ships.

The engineers at Lothal used kiln-burnt bricks to build their structures. This suggests they understood how tidal movements affect brickwork.

The Lothal dock shows incredible maritime engineering for its time. It was built as a trapezoidal structure to handle the water. The north-south arms averaged 21.8 metres in length. The east-west arms measured 37 metres. Engineers likely studied tides to choose this specific location. The Gulf of Khambhat has a very high tidal amplitude. This allowed ships to be sluiced through flow tides in the river estuary. This ancient knowledge helped them avoid the deposition of silt.

History shows how docks became more commercial over time. The Howland Great Dock was built on the River Thames in 1703. It was the first enclosed wet dock to use lock gates. At that time, it was just a haven surrounded by trees. It did not have unloading facilities. Later, the Old Dock at Liverpool was built in 1715. This was the first commercial enclosed wet dock. It included quays and unloading warehouses. It could hold up to 100 ships at once. This improved the throughput of cargo by reducing ship waiting times.

Many different terms describe the various parts of a dockyard. A dockyard, or shipyard, consists of one or more docks and other structures. In the United States, a dock is often synonymous with a pier or a wharf. A pier is a raised walkway supported by pillars. A wharf is a fixed platform, often on pilings, used for loading. The water area between piers is called a slip. In Canada and the US, a dock might be a simple wooden platform at a cottage. These structures connect our land to the vast ocean systems.