RIEGL UK’s Topo-Bathymetric Sensor Enables Step Change in Plymouth Underwater Mapping Project
- jrobinson
- Apr 8
- 3 min read
RIEGL UK’s VQ-840-GL Topo-Bathymetric LiDAR sensor has been chosen to help Plymouth Marine Laboratory (PML) and its partners revolutionise how underwater environments are mapped, particularly shallow waters like river sections and coastal areas with low turbidity.
The PML-led project has been funded through the Natural Environment Research Council Net Zero Aerial Capability (NZArC) programme.
Titled ‘A remotely piloted aerial Green LiDAR for mapping bathymetry of shallow waters and elevation of boundary land’, the project involves collaborations with British Geological Survey, National Oceanography Centre, Scottish Association For Marine Science and the UK Centre for Ecology & Hydrology (UKCEH).
Going where boats can’t go
The innovative scanning project will use RIEGL UK’s state-of-the-art aerial equipment to provide underwater mapping – bathymetry - data where other sensors struggle or simply fail to provide solutions.
Aser Mata Torollo, Project Leader and Earth Observation Scientist at PML, said: “Mapping of shallow waters is especially vital for studying blue carbon habitats such as mangroves, seagrasses, and tidal marshes as these are some of the most efficient natural carbon sinks on Earth.
“Mapping their underwater terrain and estimating carbon storage has been a major challenge.”
While bathymetry of the seabed or rivers can be obtained using other boat and instruments such as multibeam echosounders, these sensors cannot be deployed in very shallow waters.
To help deliver this important mapping, the project purchased the innovative VQ-840-GL sensor along with a dedicated third-party drone platform.
This aerial sensor will enable the research to have a reduced carbon footprint compared to the more traditional monitoring solutions that rely on aircrafts or ships, resulting in faster data collection with less environmental impact.
Jonathan Robinson, Manager – Technical Sales at RIEGL UK said: “The RIEGL sensor allows the research survey engineers to access a wide array of primary system variables such as laser pulse repetition rate (measurement rate), scanner mirror speed, laser beam divergence and receiver field of view, as well as full waveform recording and subsequent processing options.
“The harmony of hardware settings versus project specification versus external environmental factors will form part of PML benchmark testing and subsequently developed code of practices.”
ULS Technology
The high-tech sensor uses unmanned laser scanning, a remote sensing process used to create 3D models of structures and areas.
The lightweight, versatile laser scanner offers:
Estimated penetration depth of nominally 2 Secchi disks
40 degrees scan angle range
High-pulse repetition rate of up to 200 kHz
High-resolution data capture in hazardous or hard-to-reach areas
Aser added: “The system will provide the data needed to advance a myriad of scientific challenges that we are currently facing in marine ecosystems.
“It will allow more precise quantification of coastal erosion and the mapping of blue carbon ecosystems, such as kelp and seagrass, to better understand their lifecycle, improve modelling and estimate how much carbon they store, in turn paving the way to promote the restoration of these habitats for carbon sequestration.
“It will also help improve models for river flow and river discharge in support of flood prevention.”
As part of this project, the sensor will be tested and benchmarked against different bathymetric and terrestrial sensors in different environments. The results will be published and made freely available to establish a code of good practices for other projects.
Furthermore, the ultimate goal of the project is to make this capability accessible to any researcher in UK that wish to take advantage of this novel sensor via collaboration with PML.