The Hindenburg Dam is the lifeline of the island of Sylt. Its maintenance is complex, because the tides and the challenging weather conditions take their toll on the dam's substructure. The "angels" are out and about on the Hindenburg Dam in all weathers. Hannes Hein's construction team has to repair the lugs in the mud flats, as they protect the dam from excessive waves. Without the silt dredger, this work would not be possible.