Hydrographic surveys encompass the science to measure and map depth and bottom configuration of water bodies (rivers, lakes and the ocean).  Typically, hydrographic information is published as nautical charts and sailing directions which in a navigational context is fundamental to mariners in order to navigate ships safely and efficiently.  High resolution digital terrain models of the seabed / lakebed / riverbed inform engineering designs of submerged infrastructure.

Given the fact that not all submerged surfaces are easily accessible for survey measurements, sonar technology (SBES and MBES) is employed to accurately “map” the bed under the water body and create a georeferenced digital terrain model.

Trail Surveys, through strategic partnerships with local and international Hydrographic Survey Service Providers, has built a reputation delivering innovative geomatics solutions throughout the African Continent.  Our experience and ability to combine and integrate hydrographic surveys with remote sensing, engineering and cadastral survey products enables us to deliver an unsurpassed geomatics solution to our Clients, whilst discounting both time and cost on their projects.  Both conventional certified water vessels and unmanned vessels are employed.


Typical applications will comprise the following (but not limited to):

  • Hydrographic surveys to derive accurate georeferenced digital terrain models of the submerged area using single beam and/or multi-beam echo-sounding technology

  • River profiling surveys using conventional survey methodology for hydrological studies, flood line calculations, engineering design and environmental applications

  • As-built surveys of submerged structures (MBES);

  • Pollution control and mine tailing dam surveys

  • Locality Maps for Prospecting Rights Applications;

  • Locality Maps for Mining Permit Applications

  • Sedimentation surveys of dams

  • Capacity surveys of Dams

  • Determination of outlet levels on dams / reservoirs


We understand that every project, site and client is different – as are their expectations of the required survey deliverables.  In order to “sharpen the pencil” and offer you the most cost and time effective geomatics solution, fit for the purpose you require the survey, we would need to acquire the following information from you:

  • Location of the survey – ideally a “Google Earth Placemark” send to us in kml/kmz format

  • The purpose of the survey and details on the Construction Project;

  • Details on the presentation of the survey data

    • Hardcopy / Softcopy
    • CAD Specifications / Drawing Layout
    • Digital data formats required for integration into your design / cad software
  • Specific logistic constraints getting access to the specific area of interest including access to launch the water vessels (conventional / unmanned) and details of permits required.

  • SHEQ Requirements (Medicals / inductions / onboarding / PPE / Mine-ready vehicles etc)

  • Schedule / Program – Should a staggered delivery be required we can work with you to provide critical data at key dates throughout your project.