Near the city of Nijmegen Skeye carried out photogrammetric measurements at the request of engineering company RPS. A 15-kilometre corridor of a levee next to the river Waal was surveyed as part of the on-going projects to raise the level of river levees by water board Rivierenland.
The aim of the measurements was to map the entire area from the air with a special focus on measuring all terrain heights in the area between the levee and the river. Two main roads are situated in the middle of the project area as well as some congested areas. Their presence made it impossible to carry out the aerial topographic survey using a drone. Dutch regulations forbid commercial drone flights close to major roads and above congested areas. To overcome this challenge, Skeye used the in-house developed PhotoEye system deployed from a manned aircraft.
From all the individual images one seamless 3D terrain model (DTM) was created as well as an orthophoto mosaic to scale.