The Goby Reef
- Josine Beets
- Apr 24
- 3 min read
Updated: Apr 25
Last November, we found the perfect location to give our reef units from the CREST project a second life. With over 100 Purpose-Built Reef structures in tow, we headed out to Oostvoornse Lake to install them below the surface, where they collectively became the Goby Reef. What began as an idea has now become a small but meaningful stepping stone for marine life: creating new habitats for gobies, mussels, algae, trout, and eels. Next to this, it is also part of the diving route mapped by the divers of the Rotterdam Diving Association.
What is the Goby Reef?
The Goby Reef, or Grondel Rif in Dutch, is one of our latest Purpose-Built Reef (PBR) deployments. It’s located in the brackish waters of Oostvoornse Lake, where the ecosystem has been shaped by a long history of industrial activity and shifting salinity levels. Challenging for marine life, but also full of potential.
The reef units we used were first tested in the CREST project focused on low-lying islands (see our earlier blog post: Can Our Purpose-Built Reef Protect Vulnerable Coastal Regions?). Now, they have found a permanent home at 4 to 6 meters depth near the longitudinal dam, just east of FieldLab Green Economy Westvoorne, Slag Baardmannetje.
Each PBR module features natural-looking cavities that offer fish places to hide, breed, and live. Its porous, rough surface provides the ideal texture for mussels and algae to attach and grow. A central lifting hole in the design also makes the modules easy to install by divers, adding a practical touch to their ecological function. Some reef modules were placed as standalone units, while others were stacked into pyramids to create larger cavities, ideal for bigger fish species, such as trout.
Collaboration Beneath the Surface
We didn’t do this alone. The beauty of the Goby Reef lies in the network of partners who helped bring it to life.
FieldLab Green Economy Westvoorne played a central role, offering their barge, expertise, and testing location in the lake, making it possible for us to pilot this reef within their innovation zone. Local divers from the Diving Association of Rotterdam joined in to place each structure precisely, one by one. The reef has now officially been added to their dive route, ensuring a steady stream of curious (human) visitors.
The change in biodiversity around the Goby Reef will be closely monitored to see which species are settling in and how the ecosystem responds over time. Our Goby Reef has already been monitored once, three months after installation (see images below).
Challenges, and What They Taught Us
Not everything was smooth sailing. One of the biggest hurdles we faced was not in the lake, it was in the paperwork. There’s currently no clear permitting category for nature-based underwater innovations, which meant navigating a lot of ambiguity.
With support from local water authorities like WSHD, and building on our previous work, including the eco-anchor research for the floating wind turbines of TouchWind (see image below), we moved forward. Still, it is clear that regulations need to evolve to keep up with new solutions that are good for nature, communities, and innovation.
What is Next?
Monitoring is already underway, a first check was done after 3 months. We will check the reef again at 6 and 12 months, and then annually for at least three years, to study how fish, mussels, and algae take to their new home. We are especially excited about the data gathered through eDNA testing. This will help us measure real biodiversity impact, species by species.
What we learn here will ripple outward: to the North Sea, the Mediterranean, and beyond. The Goby Reef is a step toward scaling our technology in different waters, for different species, with one shared goal: restoring life.
Come Dive In!
A big thank you to everyone who made this project possible: with a special shoutout to FieldLab Green Economy Westvoorne and the divers of the Rotterdam Diving Association. Thanks to you, the reef is now part of an official diving route. If you’re in the area, suit up, take a dive, and don’t forget to scan the QR code at the FieldLab. Let us know what you spot!
