Hydrographic Surveying – Methods, Applications and Uses | The survey of physical characteristics present underwater is hydrographic surveying or bathymetric surveying. It is the technique of measuring all underwater variables that affect all marine activities, such as dredging, marine infrastructure, offshore drilling, etc.
Hydrographic Surveying – Methods, Applications and Uses
Hydrographic surveying is the science of measuring and describing the physical features of bodies of water and the land areas adjacent to those bodies of water. It is used to create nautical charts, which are used by mariners to navigate safely. Hydrographic surveying also has a wide range of other applications, such as:
- Port and harbor planning and construction: Hydrographic surveys are used to determine the depth of water, the shape of the seabed, and the location of obstructions in a port or harbor. This information is used to plan and construct new facilities, such as docks and piers.
- Offshore oil and gas exploration and development: Hydrographic surveys are used to identify potential oil and gas deposits, and to map the seabed in areas where drilling is planned.
- Coastal engineering: Hydrographic surveys are used to study the effects of waves, tides, and currents on coastal areas. This information is used to design coastal defenses, such as seawalls and breakwaters.
- Fisheries management: Hydrographic surveys are used to study the distribution of fish and other marine life. This information is used to manage fisheries and to protect endangered species.
There are a variety of methods used in hydrographic surveying, including:
- Echo sounding: This is the most common method of hydrographic surveying. A sound wave is emitted from a ship or other platform, and the time it takes for the sound wave to travel to the seabed and back is measured. This information is used to calculate the depth of water.
- Multibeam echo sounding: This is a more advanced method of echo sounding that uses a multibeam transducer to emit a fan-shaped beam of sound waves. This allows for the creation of detailed bathymetric maps of the seabed.
- Side-scan sonar: This method uses a sonar transducer that is towed behind a ship to create images of the seabed. This information can be used to identify obstructions, such as wrecks and pipelines.
- LiDAR: This method uses a laser to create a 3D image of the seabed. This information can be used to create detailed bathymetric maps and to identify features that are not visible with other methods.
Hydrographic surveying is a complex and challenging field, but it is essential for the safe and efficient navigation of ships and for the management of our coastal resources.
The information gathered from hydrographic surveying is required to create nautical charts that include,
- Available depths
- Improved Channels
- The aids to navigation harbor facility
These surveys also take part in the required collection of data concerning the design and creation of port facilities, such as the construction of piers. This helps to detect the loss of energy because of silt and many uncertainties.
Applications Of Hydrographic Surveying
- Planning of underwater cables and pipelines: Hydrographic surveys are used to identify the best route for underwater cables and pipelines. This information is used to minimize the risk of damage to the cables and pipelines during construction and operation.
- Mapping of underwater features: Hydrographic surveys are used to map underwater features, such as coral reefs, shipwrecks, and underwater pipelines. This information is used for a variety of purposes, such as environmental monitoring, marine archaeology, and navigation.
- Supporting disaster relief operations: Hydrographic surveys can be used to assess the damage caused by a disaster, such as a hurricane or tsunami. This information can be used to plan and execute relief operations.
The applications of Hydrographic surveying include:
- Dock and Harbour Engineering
- River Works
- Land Reclamation
- Water Power
- Flood Control
- Sewage Disposal
Hydrographic Surveying Uses
For nautical charting, dredging, and navigation protection, accurate hydrographic data is important. Single-beam hydrographic surveying has been the main tool used for mapping the seafloor for most of the last 50 years.
Uses of hydrographic surveying are given below:
- Depth of the bed can be determined
- Locate sewer fall by measuring direct currents
- Locating mean sea level
- Massive structures like bridges, dams harbors are planned
- Navigation Chart Preparation
- River and stream discharge measurement
- Scouring, silting and irregularities of the bed can be identified
- Shore lines can be determined
- Tide measurement
For the collection of seafloor topography data, it is an accurate and relatively simple technique.
Importance of Hydrographic Surveying
Here are some of the reasons why hydrographic surveying is important:
- Safety: Hydrographic surveys help to ensure the safe navigation of ships by providing information about the depth of water, the shape of the seabed, and the location of obstructions.
- Efficiency: Hydrographic surveys help to improve the efficiency of shipping by providing information about the best routes to take and the areas to avoid.
- Environmental protection: Hydrographic surveys can be used to monitor the effects of pollution on marine ecosystems and to identify areas that need to be protected.
- Economic development: Hydrographic surveys can be used to identify potential oil and gas deposits, to plan new ports and harbors, and to develop coastal tourism.
Hydrographic surveying is a valuable tool that is used to ensure the safety, efficiency, and environmental protection of our oceans and waterways. It is an essential part of our maritime infrastructure and it plays a vital role in the global economy.
Hydrographic Surveying Video in English
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