What are Bathymetric Surveys?
Bathymetric Surveys are a type of hydrographic survey which map out the details of underwater terrain, illustrating the depth and land that lies beneath a body of water. Data can be collected for a variety of water bodies, including rivers, lakes and estuaries, which can then be used to inform flood assessments and project developments.
Traditionally, Bathymetric Surveys are conducted using an echo sounder attached to a survey boat. As the boat moves across the water, the echo sounder will generate electrical signals which are then converted into sound waves by an underwater transducer. Sound waves will bounce off underwater features, the echo is then identified by the echo sounder and the distance to the identified feature is calculated.
Bathymetric Survey systems rely on highly accurate Global Navigation Satellite Systems (GNSS), like GPS, to link each measured distance to a particular depth on the surveying map. Then, the data captured from the boat will be transformed into an elevated model.
Bathymetric Surveys Methods
There are multiple methods and tools that can be used to produce a Bathymetric Survey, but some of the more common methods include:
- Multi-beam survey: attached to a boat, an echo sounder sends out beams across the waterbody floor. When the beams bounce back from, the floor, data is collected and processed, so that it can be viewed in real-time during the survey.
- Single-beam surveying: a single beam is sent directly underneath the boat to identify the depth of the waterbody. Typically, this method is used on smaller areas of water.
- Acoustic Doppler Current Profiler (ADCP): this method involved using soundwaves to measure velocity. The sound waves are transmitted into the water and as they reflect off sediment and other materials within the water, data is collected.
- Sub-bottom profilers: sound waves are directed at the waterbody’s floor to identify and the layers of sediment and other rocks that lay beneath the floor.
At Lucion, our preferred method for conducting a bathymetric survey is the use of a remote-control survey boat, combined with the use of echo sounding technology to identify the water depths, with positions being recorded using GPS or total station.
Why are they important?
Bathymetric Surveys can be important for a wide number of reasons, particularly in terms of supporting navigation, dredging activities and land projects:
Navigation: having an accurate survey of a body of water is crucial to enable safe navigation for boats, ships, and vessels. Bathymetric Surveys can help these watercrafts identify whether the water is too shallow for passage, which is particularly useful for rivers and harbours.
Dredging: Bathymetric Surveys are commonly used as part of the data collection process for dredging and maritime infrastructure works, as it establishes the subsea conditions and the contours of the seafloor. This vital information informs decisions regarding dredging tools that will be used and creates a baseline for measuring environmental impact and dredging accuracies.
Land Development Projects: Bathymetric Surveys are useful for land development projects, such as urban planning, bridge building and housing. These surveys identify the features of a body of water, so project plans can be developed around this information, reducing the likelihood of errors and misjudgement.
Which Business Types Would Benefit from Bathymetric Surveys?
Bathymetric Surveys can be used for a range of businesses and project types, most commonly used for the following applications:
- Land development projects, such as bridge building and housing
- Flood assessments and water resource management
- Navigation and maritime safety
- Dredging activities and harbour maintenance
- Environmental monitoring and habitat mapping
- Underwater infrastructure inspections and planning
Lucion offers efficient Bathymetric Surveys for a wide range of applications, and we are here to help you plan and execute your project with no delays or damage throughout. For more information, contact us here.
