Rocks are in demand, at least in Aalborg, Source: Unsplash

Aalborg is asking residents to donate stones, but why?

Aalborg is asking residents to donate stones, but why?

The noble mission of reviving a fjord reef for marine life will need a collective effort to materialize

The Aalborg Municipality has released an official appeal to all the local residents, especially those who have gardens, to donate any excess stones that they don’t need. If you’re puzzled by this sudden demand for the seemingly useless rocks on part of the authorities – rest assured, there’s an explanation.

The local administration is taking part in the restoration of underwater reefs in the Limfjord, the sea inlet upon whose shores the Danish city is located. The grand project, called Stenrev (Stone Reef) includes the installation and creation of several small stone reefs in different spots. The argument goes that setting up the reefs will boost the proliferation of marine life.

What’s more, the authorities have described the appeal as a way to pay back Nature its dues, since over the centuries many rocks have been fished out of the very same fjord and used in the construction of churches and piers. In fact, it is estimated that until 2010, when taking stones from the water was officially banned, some 8 million cubic metres of rock had been fished out of the waters. And now it’s time to return at least some of them back.

Reusing and recycling rocks – a solid idea

Thus, in collaboration with local farmers, contractors and a number of volunteers, Aalborg Municipality plans to get the rock reefs back into the fjord.

The stone reefs are not just a whimsical idea either. The reefs lie firmly on the seabed and are not moved by waves and ocean currents. The rocks form an environment with caves and crevices that attract fish, crabs, lobsters and other small animals. Stony reefs are important for the oxygen conditions in the sea, as seaweed and algae have a place to settle, mature and produce oxygen.

Aalborg Municipality plans to re-establish four reefs during 2023 and for this purpose, it is inviting conscientious residents to deliver any excess stones they find in their gardens to special recycling sites. The city recommends that the rocks delivered should be larger than 10 centimetres as these have more value for the project.



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