Showcasing the potential of ocean multi-use
As society moves more of our activities to the sea our European waters are becoming busier with an increase in potential conflicts and threats to ecosystems. With EU targets such as developing 60 GW of offshore wind power by 2030 and 300 GW by 2050, goals ensuring that different industries collaborate and share space to conduct their activities is crucial. Combining several activities in the same marine area can reduce demand on the space needed for different activities, help develop synergies and cost savings for the relevant undertakings, and free more room for protecting biodiversity and keep ocean water pollution free.
In synergy
The EU- and industry-funded UNITED project provides evidence that the development of multi-use platforms or the co-location of different activities in a marine and maritime space is beneficial to all parties involved. “The project aims to provide evidence of the viability of ocean multi-use through the development of five real-life ocean multi-use pilots that combine different marine activities,” says Ghada El Serafy, project coordinator at host company Deltares. In practice, this means that the same area originally designated for an offshore wind farm can be used for other compatible activities, such as seaweed, mussel or oyster farming. The space between wind turbines provides enough space for sustainable farming and also tourism activities such as boat trips. Another example of multi-use is having diving tours explore fish farming at sea, where people can learn about aquaculture, and also collect data for environmental monitoring and farming operations.
Success in the face of challenging circumstances
The five project models have produced promising results. The German pilot cultivated shellfish and macroalgae at different water depths using different materials, growing medium, and designs within a difficult, exposed offshore site with many technical challenges such as waves of 16 m and currents of 1.5 m/sec. “Despite the patchy growth, the success of the seeded areas exceeded expectations,” says El Serafy. “The successful seaweed and mussel harvest serves as a testament to the unwavering dedication and technical, biological and logistical expertise of the German pilot. Their innovation and sustainable and safe offshore practices has earned them well-deserved recognition within the offshore industry.” Two additional pilots explored seaweed and mollusc farming in dynamic offshore wind parks, the Dutch and Belgian pilots. The Belgian partners have simultaneously progressed with restoring oyster beds within wind parks with the ambition to have these natural beds seed oyster farming activities. Oyster reefs provide several ecosystem services, including enhanced water quality through their filtering capacity, improved sediment stability and carbon sequestration. These oyster reefs are dually important as breeding grounds, food sources and resting or refuge places for a wide spectra of biodiversity. A recent harvest of several seaweed nets at the offshore Belgian pilot site represents the first time that seaweed has been successfully cultivated and harvested within an active offshore wind farm in Europe. Seaweed farms, particularly within wind parks, stand to provide a refuge and shelter for various marine species, as an extractive aquaculture method can be a manner through which excess nutrients from onshore activities can be removed and remediated. Combining oyster aquaculture and seaweed farming can therefore offer a sustainable way of performing aquaculture and purifying the surrounding water from excess nutrients.
Benefiting local communities
The pilots showed that multi-use platforms or co-location of different activities in a marine and ocean space is economically, socially and environmentally viable for European maritime industry and that they can operate sustainably in healthy local ecosystems, while supporting, safe, socially accepted sustainable businesses. “The ultimate beneficiary is society at large given the fact that the project, and specifically its pilots, are looking into the socioeconomic benefits of the ocean multi-use concept implementation,” El Serafy sums up. This means that the multi-use of offshore sites is expected to yield economic benefits and stimulate job creation through the integration of activities such as aquaculture and tourism.
Keywords
UNITED, ocean multi-use, offshore wind, marine, tourism, biodiversity, aquaculture, coastal communities
