Seabed Mapping in Norway’s Largest Lake
Using the NORBIT WINGHEAD i80S for high-resolution underwater mapping
This autumn, Norwegian University of Science and Technology (NTNU) carried out a pilot project for advanced seabed mapping in Lake Mjøsa, an operation that required high precision, a complex mobilisation setup, and reliable sensor technology. For this pilot, NTNU rented a NORBIT WINGHEAD i80S multibeam sonar, including the integrated INS and all necessary software, from NOR Offshore Rental.
- Lake Mjøsa is Norway’s largest lake, located between the cities of Hamar, Gjøvik and Lillehammer, with an estimated maximum depth of 453 meters.
- NTNU AUR-Lab is among Norway’s foremost research environments for autonomous marine operations.
The pilot phase covered a total of 25 km² of seabed outside Gjøvik and Hamar, using the autonomous surface vessel USV Grethe under the direction of NTNU’s Department of Marine Technology, AUR-Lab.
Why map Lake Mjøsa?
Although Mjøsa is Norway’s largest lake, much of the existing seabed information is old, fragmented or incomplete. The depth data that exists today is largely based on earlier measurement methods and does not provide the level of detail required for modern use.
The lack of modern, high-resolution seabed data makes it challenging to conduct safe and precise marine operations. Without reliable depth information, planning, navigation and risk assessment become difficult. Updated data is also essential for environmental mapping, research and emergency preparedness.
Stable performance in a technically demanding setup
The NORBIT WINGHEAD i80S delivered consistently stable results throughout the operation, despite challenging mobilisation conditions and highly variable depth profiles in the lake.
“In a technically demanding setup onboard USV Grethe, the NORBIT WINGHEAD i80S multibeam echosounder provided stable performance from start to finish, with excellent data across the full depth range. The fully integrated INS and built-in NTRIP client enabled very rapid mobilisation and verification,”
— Christian Malmquist, NTNU AUR-Lab / Kartverket
Image: NTNU
NORBIT WINGHEAD i80S
Key features
- 0.5 x 0.9 degree resolution
- Frequency agile between 200 – 700kHz
- Weight less than 9kg
- Integrated GNSS/INS with roll and pitch stabilization (yaw optional) keeps data stable, even on moving USVs.
- SV probe integrated in the sonar head.
- One cable from topside to sonar head reduces complexity and operational risk.
- Standard delivery includes backscatter (intensity, snippets, sidescan) and water column data.
- Fully supported by all the usual third-party acquisition and post-processing software.
From delivery to field-ready in just a few days
Working closely with Norwegian University of Science and Technology’s engineering and field teams, and with technical support from the Norbit service team, the system was quickly installed and prepared for data collection.
The mobilisation included:
- fast delivery of the NORBIT WINGHEAD i80S and associated software
- mounting, integration, calibration and testing
- a mobile setup that can be transported by trailer
- the ability to mobilise globally and operate remotely from NTNU’s control room in Trondheim
The entire process, from receiving the equipment to becoming fully operational in the field, was completed in just a few days.
NTNU’s field team highlights the quality of the delivery:
“We would like to highlight the good service, fast delivery of equipment and software, and clear agreements provided by NOR Offshore Rental during the mobilisation, data acquisition and demobilisation phases,”
— Martin Bredesen, Field Engineer, NTNU
Image: NTNU
Pilot results: The mission expands
Following the successful pilot, Norwegian University of Science and Technology has now been commissioned to map the entirety of Lake Mjøsa. The work will continue over the next 2–3 years and will include full mapping of the lake’s depth and topography.
Supporting safe and efficient data acquisition
NOR Offshore Rental is honored to support NTNU AUR-Lab and Kartverket in a project of national importance. With reliable equipment, fast response times and solid technical expertise, we help enable safe and efficient operations both in Norway and internationally.