Bathymetry Surveys: Uncovering the Underwater Landscape

When we think of mapping, we often picture a road atlas or a GPS display showing city streets, mountain ranges, and valleys. However, mapping isn't just limited to the land; it extends beneath the water's surface as well. Bathymetric surveys are specialised surveys that map underwater landscapes, helping us understand the hidden terrains beneath oceans, rivers, and lakes. 

So what is Bathymetry?

Bathymetry is the study of underwater depths of ocean floors, lake beds, canals, ports and other water bodies. It is akin to topography, which is concerned with mapping land elevation. Underwater mapping surveys involve the measurement of the depth and shape of underwater terrain to produce detailed maps that reveal the topography of seabeds, riverbeds, and other underwater features.

Why Are Bathymetric Surveys Important?

Understanding the underwater landscape is crucial for several reasons:

• Navigation and Safety: For maritime navigation, understanding the depth and shape of the seabed is essential to avoid hazards. Bathymetric charts are vital for ship routing, avoiding underwater obstacles, and ensuring safe passage.
• Environmental Protection: Bathymetric data helps environmentalists and researchers monitor underwater habitats, assess the health of marine ecosystems, and plan for conservation efforts. It is also essential for studying the impacts of climate change, such as sea-level rise and coastal erosion.
• Engineering and Construction: Bathymetric surveys are crucial for planning and executing marine and civil engineering projects, such as constructing bridges, piers, offshore wind farms, and underwater pipelines. Accurate underwater mapping ensures that structures are built on solid foundations and helps avoid costly mistakes.
• Resource Management: Bathymetric data is used in the exploration and management of underwater resources, such as minerals, oil, and gas. It helps in the strategic placement of drilling platforms and underwater mining equipment.
• Recreation and Tourism: Bathymetry is useful for activities like scuba diving, fishing, and tourism. Detailed underwater maps allow enthusiasts to explore underwater landscapes safely and enjoyably.

How Are Bathymetric Surveys Conducted?

We use a multitude of data collection methods to produce the best possible results. Our bathymetric surveys leverage a range of technologies, including:

• Total Stations and GPS: These tools provide accurate positional data for watercourse structures and nearby topographic details.
• LIDAR (Light Detection and Ranging): In shallow waters, LIDAR technology can be used by aircraft to measure the depth of water bodies. It is efficient for coastal mapping and shallow-water bathymetric surveys.
• USV (Unmanned Surface Vehicles): These remote-controlled or autonomous vessels equipped with echo sounders and sonar are perfect for surveying difficult-to-reach areas and collecting high-precision data.
• Multi-Beam Echo Sounders: These systems use multiple beams of sound to cover a wide swath of the seafloor in a single pass, providing high-resolution maps ideal for detailed exploration of underwater terrain.

Using these specialised surveying equipment, we can accurately plot the positions of watercourses, watercourse structures, and nearby topographic details.

 

This allows for precise mapping and assessment, which is critical for planning, design work, maintenance, flood risk assessment, ecology management, and hydraulic modelling.

How Bathymetric Surveys Benefit Your Business

Bathymetric surveys offer valuable insights and data for a wide range of businesses and project types. They are commonly used in the following applications:

• Dock and Harbour Engineering: Ensuring safe and efficient harbour and dock operations by mapping the underwater landscape to prevent potential hazards and improve construction projects.
• Flood Management and Prevention: Providing essential data for assessing flood risks, planning flood defences, and developing strategies to minimise flood impact on communities and infrastructures.
• River Maintenance: Supporting the maintenance and management of river channels to ensure smooth water flow and prevent silting, erosion, or other issues that can arise from changing underwater topography.
• Irrigation: Assisting in the planning and management of irrigation systems by offering precise data on watercourse depths and flow patterns.
• Waterpower: Enabling the effective placement and operation of hydroelectric plants by providing detailed underwater topography and water flow information.
• Sewage Disposal: Ensuring the safe and environmentally sound disposal of sewage by mapping underwater paths and depths, which helps in the proper planning and implementation of sewage systems.

Our surveys are referenced back to OSGB36 & ODN height, ensuring that all data is consistent with the UK's national geodetic and height systems. The outputs of our bathymetric surveys can include but are not limited to, cross sections, elevations of structures (such as weirs, sluices, culverts, and bridges), topographic surveys, and bed levels. 

To see some of our recent work and understand how our surveys are applied in real-world scenarios, check out our latest projects here.

Discover Precise Bathymetric Surveys with Southwest Surveys

If you’re a business in the Southwest seeking reliable bathymetric surveys, Southwest Surveys offers expert solutions to explore and manage underwater landscapes. With a commitment to accuracy and comprehensive data, we support industries in safe navigation, environmental protection, and sustainable development. Contact us today to learn how our services can benefit your next project.