Parts of the northern mole in Bremerhaven collapsed on Thursday night.
The water police are currently busy securing the now leaning mole tower, a spokesman said in the morning.
The entrance to the Geeste was therefore blocked.
The Weser ferry service also had to be discontinued.
As the shipping company announced, replacement traffic is planned.
The necessary duration of the blocking initially remained unclear.
The affected area had apparently been dilapidated for years.
The “Nordsee-Zeitung” reported first.