Why Conduct a Bathymetry Survey and Ways to Do It

Have you asked yourself how engineers build marine constructions? More than 70% of water bodies cover the planet, and humans have been exploring underwater for thousands of years, called bathymetric survey or seafloor mapping. 

Early techniques used heavy cable or rope lowered over a ship’s side until it reached the sea bed, making it time-intensive and inaccurate. As technology progresses, experts now use modern devices, like bathymetric survey equipment, to analyze echo sounders’ data in their vessels. 

What Is a Bathymetric Survey?

Bathymetry is the study of beds or floors of water bodies, including rivers, streams, oceans, and lakes. The term “bathymetric” originally came from two Greek words: “bathys,” which means “deep,” and “metrike,” which means “to measure.” 

A bathymetric survey (fathometric survey) allows experts to study and map the depth and shape of water bodies. It shows an exact representation of the seafloor, including its elevations, any scour around submerged structures, and irregularities. It also examines the surrounding tides, shorelines, currents, and waves to view the overall situation of the area.

For your bathymetric survey equipment needs, make sure to contact reputable suppliers, like R2Sonic. Check their “visit us” page to see their portfolio.

Ways to Conduct a Bathymetric Survey 

  • Single-beam surveying. Single-beam surveying measures the water depth directly under the boat, commonly used for smaller bodies of water.
  • Multi-beam surveying. This method is usually conducted in larger bodies of water, utilizing a multibeam echo sounder attached to a boat. The device maps a swath of the seafloor under the vessel by sending out multiple, simultaneous sound waves at once in a fan-shaped pattern that they can read in real-time on the boat. 
  • Sub-bottom profilers. Sub-bottom profilers are commonly used to view the layers of rocks and sediments under the floor of a water body. Experts use a transducer, which penetrates and sends a sound wave to the seabed of the water body. They then map the returned sound waves to show the layers beneath the floor of the water body.
  • Acoustic Doppler Current Profiler (ADCP). It is an instrument to measure how fast water moves across an entire water column. It is anchored to the seafloor to measure the current speed of the bottom and equal intervals until the surface.
  • Ecomapper Autonomous Underwater Vehicle. This method can collect detailed bathymetric data in places that are hard to reach by boat, using side-scan sonar and a Doppler velocity log. 

Purposes of Bathymetric Surveys

1. Planning and Construction of Dams, Docks, Harbors, and Other Marine Structures

Engineers need to ensure that the depth of the water in and around ports is enough for ships to enter and berth safely. In addition, the sea beds that support floating structures must have a strong foundation. 

On the other hand, when constructing dams or other marine structures, they need enough knowledge of the surrounding terrain to ensure the structure’s strength.

2. Aid in Flood Control Systems

Through underwater surveying, experts can predict potential flooding zones. They will identify how the ocean floor changes around the coastline and find connections to past flooding and tsunamis records. This way, they can recommend safety measures to combat disasters. 

3. Studies and Research

Through surveying, the government can determine the shorelines that extend around a coast. They use these shoreline charts to conduct studies on the effect of water bodies on land and identify the actual maritime border of countries. This data also helps countries in launching space shuttles and rockets.

4. Ship Navigation

Bathymetric survey results are used to help identify the possible paths that a vessel can safely take since some ocean routes may have rocks and coral deposits or low depths that pose a danger to ships. 

5. Dredging

Dredging means the removal of sediments, debris, and rocks at the seabed of lakes, harbors, rivers, and other water bodies. Because sedimentation (gradual filling of channels and ports with sand and silt) naturally occurs, the shipping industry needs to maintain or increase the depth of navigation channels, anchorages, or berthing areas for the safe passage of ships and boats. 

They use the bathymetric survey results as the basis for this process.

6. Pipeline System Installation and Maintenance

When laying seabed pipelines, engineers need to conduct an underwater survey to inspect the pipe, its surface, and the surrounding area of the installation. They use sonar pipeline inspection equipment, and the inspection continues for maintenance and repair.

When looking for suppliers of pipeline inspection products, it’s always best to visit their “about us” page to see who they are and their services.