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Derwent Reservoir Case Study

Investigating possible accuracies of aerial survey in areas of shallow surface water

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When surveying open landscapes it is not unusual to encounter areas of surface water. The question we asked ouselves was "is it possible to obtain ground levels under shallow water, within an acceptable level of error?"

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In order to investigate this question we carried out a test flight at Derwent Reservoir. This site was chosen partly because of its known slope underwater and partly because its challenging flight environment provided a good training flight. The flight was planned for a day when there was little wind in order to minimise rippling of the water surface.


From the resulting point cloud, sections were taken and compared against original design drawings to quantify the accuracy of the computed data. It was found that depths of water could be reasonably estimated down to around 1.5 metres.

The full article can be read online on the Geomatics World website here