To ensure that ships can navigate safely in the harbor, it is crucial to know how deep the water is. To this end, the water depth is regularly measured. However, if there is silt on the bottom, there is sometimes a layer of silt and water at the interface between the seabed and the water, somewhat like thick cocoa. Can ships navigate safely through this? The HPA is investigating this together with its partners from Rotterdam and Antwerp in the “Nautical Depth” project.

One of Germany’s most important infrastructure projects has been completed: the dredging of the Lower and Outer Elbe, also known as the Elbe Deepening. It secures the future of Germany’s largest seaport. Yet the debate continues. Is the dredging project a success, or has it failed economically and environmentally, as is sometimes claimed? A fact check.

The HPA Hydro Portal is a new digital tool for viewing, exploring, and exporting nautical depth data. It makes it easy and safe to plan and manage vessel movements.

The KAISHUU dredger doesn’t usually dock. This large hopper dredger is in operation 24 hours a day, 7 days a week, working to permanently remove excess sediment from the Port of Hamburg. We spent a day with it, accompanied by our film crew.

Every summer, oxygen levels in many parts of Hamburg’s tidal Elbe drop below a level that is critical for fish. This can result in fish kills. Why does this happen? How have fish populations changed? What impact do our dredging operations have? And what can we do about it? We have the answers.

Especially in hard-to-reach or shallow harbor areas, we need to know exactly how much water remains beneath the ships' keels. The echo.1 survey drone is now helping us with this.

Whether it’s Bremen, Antwerp, Rotterdam, or Hamburg—all ports have one thing in common: to ensure that ships can enter and leave unimpeded, excess sediment must be dredged and removed on an ongoing basis. But how do other ports handle this? What’s the same, and what’s different?

When areas of the harbor have become too shallow due to silting, we restore the necessary depth for ship traffic. To do this, the silt is inspected and dredged. Most of it is relocated within the water. A small portion must be processed and disposed of on land.

To ensure that ships have access to the necessary water depths, millions of tons of silt are dredged from the Port of Hamburg every year. But where does this material end up? Our map shows the current disposal sites in the Elbe and the North Sea.

The Elbe is subject to currents flowing from two directions: the upper reaches of the river and the sea. While the upper reaches of the Elbe carry suspended matter toward the harbor, the incoming tide washes sandier material from the North Sea into the city. In the harbor, the particles settle to the bottom as sediment.

The Elbe hasn't always had the best reputation when it comes to water quality—in the past, many pollutants were discharged into the river. In Hamburg, the river's final stop before the North Sea, contaminated sediments accumulated. But times have changed.

The difference in water level between high and low tide in the Port of Hamburg is approximately 3.80 meters. We experience this tidal range on the Elbe several times a day. This process moves large amounts of sand and silt, which settle in the navigation channel and in the port.