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Concrete blocks in the shape of cocoons were installed in the sea of Guamaré in a project that united Petrobras and UFC to support artisanal fishermen and test a little-known underwater solution, with scientific monitoring and structural results that draw attention due to the simplicity of the intervention.
Concrete blocks molded in the shape of “cocoons” were installed in the sea of Guamaré, in Rio Grande do Norte, in a project created to support artisanal fishing and test artificial structures in the Brazilian coastal environment.
In the initiative, Petrobras and Federal University of Ceará combined engineering, scientific monitoring, and traditional use of the sea in an experiment conducted on the Potiguar coast, where the relationship between coastal communities and fishing activity has a strong regional presence.
Known as Project Marambaia, the experiment was described in an article published in the journal Arquivos de Ciências do Mar, of the Federal University of Ceará, which recorded the installation of the concrete structures and the technical monitoring carried out during the analyzed period.
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According to the study, the pieces were placed in the sea as part of an action aimed at supporting artisanal fishing in Guamaré, a Potiguar municipality marked by coastal activities and the strategic presence of Petrobras in Rio Grande do Norte.
Among the points that draw the most attention is the type of material used, as the project did not resort to metal platforms, adapted vessels, or improvised structures, but to concrete pieces called cocoons.
Due to their shape, the cocoons were designed to remain at the bottom of the sea and function as artificial support points for artisanal fishing activity, in an underwater intervention that combined traditional practice and scientific monitoring.
Concrete cocoons in the sea of Guamaré
On the northeastern coast, there was already a tradition of building structures known as marambaias, fishing grounds, or caiçaras, practices used by coastal communities to create references and support points linked to artisanal fishing.
In Guamaré, this logic gained a technical scale, with the participation of a public university, involvement of a state-owned company, and scientific monitoring aimed at observing the behavior of the structures over the years.
According to the UFC article, the Marambaia Project was initiated by Petrobras in partnership with the Federal University of Ceará in 1999, within a proposal aimed at the installation and evaluation of artificial structures.
During four years of monitoring, the research followed the behavior of the casings from their installation in the sea until 2004, observing the permanence of the pieces and their structural conditions in the coastal environment of Guamaré.
For coastal engineering, the most relevant data was the stability of the pieces, as the structures of the casings did not show structural modification during the monitored period, as recorded in the university study.
This result shows that the concrete blocks withstood the conditions of the marine environment without significant alteration in the physical form monitored by the researchers, an essential point for evaluating the feasibility of such submerged interventions.
Coastal Engineering and Scientific Monitoring
Maintaining structures on the seabed requires that the material withstand currents, sediment movement, and prolonged exposure to saltwater, especially in coastal areas used by workers who depend on the predictability of the maritime space.
In the case of Guamaré, the concrete was not treated as waste, debris, or improvisation, but as a planned, installed, and monitored structure within a program associated with the support of artisanal fishing.
This difference separates the project from interventions made without technical monitoring, as the participation of the UFC allowed for data recording, observation of the structures’ conditions, and documentation of the experience in a scientific publication.
Meanwhile, the presence of Petrobras inserted the initiative into a region where the company has a history of activity related to the energy sector, coastal infrastructure, and relations with communities that use the coast as a workspace.
Artisanal Fishing and Traditional Use of the Coast
Guamaré gives weight to history by being in an area marked by the coexistence between coastal communities, economic activities, and continuous use of the sea as a space for movement, work, and organization of artisanal fishing.
In this scenario, the installation of artificial concrete structures has gained value both for applied engineering and for the debate on planned ways to support workers who directly depend on the coastal environment.
Although the image of concrete thrown into the sea may seem strange at first glance, the casings followed a simple logic: creating fixed and recognizable points in the marine environment to support a traditional activity.
The intervention, which could seem risky without technical context, was accompanied by scientific monitoring and described in an academic article, with data on the permanence of the structures during the period analyzed by the university.
The term “marambaia” also helps to understand the cultural dimension of the initiative, as it appears in the Northeast linked to structures used as a reference for artisanal fishing and built from practical knowledge accumulated in coastal communities.
In Guamaré, this traditional concept received a planned version with concrete pieces, organized installation, and university monitoring, bringing together local knowledge, coastal engineering, and scientific evaluation in a single project.
Marambaia Project and Artificial Structures in Brazil
The UFC publication frames the Marambaia Project within a broader movement of implementing artificial reefs and support structures for artisanal fishing in Brazil, focusing on solutions adapted to the coastal environment.
In the case of Rio Grande do Norte, the experience combined local tradition and engineering without relying on large visible works from the surface, as the most important part of the project remained installed on the seabed.
Precisely because it is out of sight for most people, the initiative arouses curiosity and differentiates itself from coastal works seen on beaches, jetties, ports, or containment structures near the sand.
Even so, the installation required planning, material selection, technical participation, and subsequent monitoring, elements that reinforce the structured nature of the project described by the Federal University of Ceará.
In the article, the casings do not appear as an improvised solution but as part of an organized program, using concrete structures and monitoring the behavior of the pieces over four years.
Among the recorded data, the absence of structural modification during the monitored period helps explain why the experience remains relevant for discussions on coastal engineering and submerged interventions in Brazil.
Petrobras, UFC, and Concrete on the Seabed
Little-known Brazilian projects can also involve simple engineering solutions with local impact, especially when they start from common civil construction materials adapted for specific purposes in the marine environment.
In Guamaré, this combination of concrete, sea, and artisanal fishing created a contrast capable of arousing curiosity, as submerged blocks installed by a partnership between Petrobras and the university seem, at first glance, too heavy an intervention for the coast.
Scientific monitoring, however, shows that the project was recorded, monitored, and analyzed based on technical criteria, dispelling the idea of simply dumping material on the seabed.
The experience also reinforces the importance of differentiating planned and monitored projects from irregular disposal, as the case described by the UFC involves structures designed for a specific purpose and evaluated within a program linked to artisanal fishing.
By transforming concrete blocks into pods installed at the bottom of the sea, the Marambaia Project opened up space for a little-known discussion about Brazilian coastal engineering, traditional ocean use, and planned solutions for coastal communities.
Do you think projects with concrete blocks monitored by universities should be used more on the Brazilian coast, or does this type of intervention still need to be approached with caution?
