Case study by SPH Engineering · Bathymetry · Mining
Drone bathymetry for a tailings pond at Oyu Tolgoi mine
Since 2025, survey company Best Survey has monitored a water pond inside the tailings storage facility (TSF) at the Oyu Tolgoi mine in Mongolia with a drone-mounted echo sounder from SPH Engineering. No boat goes on the water.
The challenge
Water bodies inside a tailings storage facility need regular surveys. Mine teams use them to monitor water levels, see how depth is distributed, track change over time and spot risks such as uneven deposition or sediment build-up.
At this pond, a crewed boat or an uncrewed surface vessel was not an option: there was no safe place to launch a vessel of any size. A boat survey would also have meant:
- people working on the water, exposed to site risks;
- parts of the pond that are hard to reach because of shallow zones, shape or site restrictions;
- extra logistics every time, which makes frequent repeat surveys slow.
The solution
Best Survey switched to a drone-based bathymetric workflow. A DJI M350 RTK carried an SPH Engineering bathymetry kit with an EchoLogger ECT D052S echo sounder and the SkyHub onboard computer. The survey lines were planned in UgCS flight planning software, so every flight follows the same structured pattern across the pond.
The drone is flown remotely, so the survey team stays outside the survey area for the whole mission.
The result
- Georeferenced bathymetric maps showing depth across the pond.
- Safe data collection without anyone going on the water.
- A repeatable workflow that fits the mine's ongoing monitoring schedule.
SPH Engineering notes that the same non-contact workflow is used on industrial ponds and on produced-water ponds in oil and gas, where operators track remaining capacity and sediment build-up.
Where this applies in India
Indian mines, power plants and process industries manage many ponds that are unsafe or impractical to survey by boat. The same approach suits:
- tailings ponds and water reservoirs at mining sites;
- ash ponds, effluent ponds and industrial water storage;
- quarry lakes and pits where launching a boat is difficult;
- any pond that needs frequent, repeatable depth and volume checks.
Tell us the site and how often you need to survey it, and we will specify the kit. SPH Engineering's bathymetry training is also available through HobiTech.
The equipment, available from HobiTech
| Drone | DJI Matrice 350 RTK |
| Echo sounder | EchoLogger ECT D052S |
| Onboard computer | SkyHub by SPH Engineering with the SkyHub echo sounder software |
| Flight planning | UgCS - Drone Flight Planning Software |
Case study by SPH Engineering, published April 2026. This page summarises it in our own words; the project was carried out by Best Survey, not by HobiTech. Read the original case study on SPH Engineering ↗
Need to survey a pond without a boat?
Send us the pond size, depth range and how often you survey. We will specify the drone, echo sounder, SkyHub and UgCS setup, quoted in rupees with a GST invoice.