Hydro Int. Performs Normandy Hydrographic Survey

In the summer of 2013, several Hydro International and individuals volunteered to conduct a hydrographic survey off the D-Day beaches of Normandy, France.

The first phase of the survey was conducted over the course of 27 days. The purpose of the survey was to collect as much data as possible with multibeam sonar to create a map of both bathymetry and sidescan data. Throughout the survey the survey lines were adapted as the end neared to ensure that the dataset was complete without any gaps. This required assessing the importance of some areas to determine whether they should be eliminated or preserved.

One aspect of the survey was to locate and identify possible targets that could be missing tanks. Of the tanks launched on D-Day at Omaha beach, 27 of the 29 were lost before they reached the beach. The tanks left the landing craft in deeper water with the intention of propelling themselves to the beach, but rough water conditions resulted in many of them sinking before reaching the objective. Many of the planned lines running parallel to the beach were in excess of 40 kilometres long. The line spacing was 140 metres with the sonar set on an 80 metres range scale.