Hydrographic Surveying

Conducting Hydrographic Surveys

There are a few different ways to conduct a hydrographic survey. Traditionally, ships would use echo sounding to measure the water depth. Today, there are more sophisticated methods that use things like multibeam echo sounders and even airplanes. The data collected in a hydrographic survey is used to create maps and charts that show important features of the underwater world.

Hydrographic surveys rely on advanced sonar technology to map the underwater world, revealing details about the composition and shape of the seabed.

Hydrographic surveys are conducted in a wide range of water bodies, including rivers, lakes, winding channels, sheltered areas, and coastlines.

These surveys encompass both shallow and deep waters, extending from the tidal zone where land and water meet to the depths of the ocean floor.

By providing detailed underwater maps, hydrographic surveys play a vital role in protecting our coastal ecosystems and ensuring safe navigation in these areas.

Hydrographic surveyors act as the underwater cartographers, supplying crucial information for coastal health, safe navigation, disaster response, efficient dredging, and seabed development.

Underwater Mapping Services

1. RealMapInfo boasts a comprehensive fleet for diverse surveying projects. This includes trailerable vessels ranging from 10 to 27 feet, a compact and maneuverable 6-foot remotely operated Z-boat, and dedicated support vessels.
2. Our team is comprised of top-tier professionals, including ACSM-certified hydrographers, USCG-licensed boat captains, and experienced hydrographic technicians.
3. Leveraging our advanced equipment, these highly skilled specialists deliver efficient, accurate, and safe solutions for all your hydrographic surveying requirements.

Don't hesitate to reach out to RealMapInfo LLC for these innovative hydrographic services.

Available Hydrographic Surveys

We perform the following types of surveys: single beam sonar, multibeam sonar, side scan sonar, magnetometer and sub-bottom profiling:

• Single Beam Sonar, also known as single-beam acoustic depth sounding, is a popular method for measuring water depth. It works by emitting a sound pulse from a transducer mounted on a vessel and then recording the time it takes for the echo to return. This allows for calculating the distance to the seabed. RealMapInfo leverage a special type of single-beam sonar – dual-frequency echosounders. These emit sound waves at both high and low frequencies. This proves advantageous in areas with heavy silt deposits (fluff layer) because unlike conventional single-beam sonars that use high frequencies and only measure the top of the silt, dual-frequency models can penetrate deeper and provide a more accurate reading of the actual seabed depth. An additional benefit of single-beam sonar is faster data processing compared to multibeam sonar. This makes it a suitable choice for various applications, including beach nourishment projects, shallow water environments (less than 12 feet deep), and situations where obtaining complete bottom coverage is not necessary.
• Multibeam Sonar, also known as acoustic multibeam survey systems, comes into play for projects requiring comprehensive underwater mapping, particularly in deeper waters (usually exceeding 12 feet). Unlike single-beam sonar that focuses on a single point directly below the vessel, multibeam systems emit a fan-shaped sound wave, enabling the collection of data across a wide swathe of the seabed in one go. This technology excels in various applications, including: Project condition surveys: Gaining a detailed picture of a project's underwater structures and their condition. Dredging measurements: Precise measurement of dredged material volume for efficient project management. Channel clearance assessments: Ensuring channels are clear and meet navigational depth requirements. Construction payment surveys: Providing accurate data for calculating payments based on completed underwater work. Additionally, multibeam systems can be configured for incredibly wide coverage, exceeding 180 degrees. This allows for "side-looking" capabilities, enabling the creation of comprehensive underwater topographic maps of confined spaces like channels, lock chambers, dams, and other underwater structures.
• Side Scan Sonar, is a powerful underwater imaging tool that creates detailed, wide-range pictures of the seabed on either side of a survey vessel. Unlike single-beam sonar that provides depth readings from a single point, side-scan sonar works like an underwater camera, offering a visual representation of the seafloor. This method provides valuable information, including: The relative height of objects: By analyzing the position of objects in the side-scan image, surveyors can estimate their height in relation to the surrounding seafloor. Identification of potential hazards: Shipwrecks, pipelines, and other underwater structures can be located and mapped using side-scan sonar data. While side-scan sonar estimates object height, it doesn't provide exact depth measurements. However, it can be effectively combined with multibeam sonar technology. Multibeam sonar precisely measures the depth of objects identified in side-scan images, creating a complete underwater picture.
• Magnetometer are instruments that act like metal detectors for the ocean floor. They measure variations in Earth's magnetic field, which can be caused by objects made of iron or steel. This makes them uniquely suited to finding things that might be invisible to other underwater imaging techniques like side-scan or multibeam sonar. Magnetometer surveys are a valuable tool in various applications, particularly for: Locating ferrous objects: Anchors, cables, pipelines, lost dredging equipment, shipwreck debris, and even underwater munitions can all be detected by magnetometers due to their ferrous (iron-containing) nature. Identifying aircraft and engine remains: Magnetometers can help pinpoint submerged aircraft and engines due to the presence of ferrous metals in their construction. Overall, magnetometers offer a complementary approach to underwater surveys, uncovering objects that might be missed by other sonar technologies.
• Sub-bottom profiling utilizes low-frequency sound waves to act like an underwater X-ray. It penetrates beneath the seabed, revealing the layers of sediment or rock that lie hidden below. This powerful technology offers valuable insights for various applications, including: Bridge and shoreline scour surveys: By mapping the composition of the seabed near bridges and shorelines, engineers can assess the risk of erosion or scouring, which is crucial for ensuring structural integrity. Buried object location: Sub-bottom profiling can help locate pipelines, cables, or even shipwrecks that are buried beneath the seabed. Geohazard surveys: This technology plays a vital role in identifying potential underwater hazards like landslides or buried pockets of gas. Geological studies: By analyzing the layers revealed by sub-bottom profiling, geologists can gain a deeper understanding of the history and composition of the seabed. Mining and dredging surveys: This method allows for the mapping of valuable resources or the identification of potential challenges during dredging projects.

Experience the RealMapInfo LLC difference today. We're ready to assist you. Call today for more information.