Sediment, policy and partnership: Colombia charts a new course for dredged material

Every year, dredging vessels pull some 3.6 million cubic metres of sediment from the waters around Barranquilla, where Colombia’s Magdalena River meets the Caribbean Sea. Almost all of it is currently discarded. An ambitious collaboration between the Netherlands and Colombia is working to change that.

The project was brought together under the Partners for Water programme and led by Arcadis in consortium with Colombian engineering firm JESyCA, Fundación Herencia Ambiental Caribe and Netics. The goal was straightforward: partner with Colombia to identify the building blocks to construct the legal and procedural foundation needed to put dredged material to beneficial and sustainable use. After a year of intensive work, the project formally closed with an event in Bogotá on 26 March 2026.

A resource hiding in plain sight

In Colombia, dredging is not optional. The country’s rivers carry enormous sediment loads, constantly depositing material in ports and navigational channels. The Magdalena River alone drains a vast Andean watershed. Without regular dredging, trade along these waterways effectively stops.

While dredging is routine, nothing useful is done with what is removed. “Currently, it’s disposed of,” says Pilar Vasquez, a biologist at Fundación Herencia Ambiental Caribe and one of the project’s lead researchers. Disposal follows a defined set of quality assessments and upon completion, the sediment is sent to designated sites.

It’s a significant waste. About half of the material typically dredged is either clean or sufficiently clean to reuse. Once dried, the sediment’s physical and chemical characteristics are similar to extracted raw material and sometimes even better, offering nutrients that can support nature restoration.

In the Netherlands, instead of importing clay, clayey dredging material is being used to reinforce sea dykes and to construct new islands, combining improving water quality and boosting biodiversity (Marker Wadden). In addition, compressed dredging material has been shaped into artificial reef elements that restore underwater habitats (GEOWALL). The shift in thinking is not complicated rather than asking where to dump dredged material, instead you can ask where can it go to do the most good.

Learning from ten countries

The first phase of the project looked closely at the Dutch experience. The Netherlands has spent decades refining its approach to dredging material with one principle standing out as particularly interesting. In the Netherlands, permissible contamination limits are set according to what the material will actually be used for and not just the sediment’s quality in isolation. “This is very important,” Pilar says. “It differs from many other countries, where limits are established, regardless of how you’re going to use the sediment.”

The team reviewed regulatory frameworks from ten jurisdictions, searching for examples that resembled Colombia’s tropical context. Dutch standards, developed for a small, temperate, geologically uniform country cannot always be directly applied. Colombia is something else entirely with enormous diversity in terms of geology, climate, ecology and living organisms. For example, what would apply for the Caribbean coast would not necessarily apply to the Pacific coast or the Amazon basin.

Two regions ultimately emerged as the best references: Florida (USA) and Brazil. Both are tropical regions that have developed their own use-based approaches to sediment. The Colombian Ministry of Environment’s plan is to take these two as a starting point, setting initial thresholds while continuing to gather local data to refine them over time.

A case study in Barranquilla

The next phase looked at what beneficial use could look like in practice in the Colombian context. The team focused on Barranquilla, capital of the Department of Atlántico situated at the mouth of the Magdalena river and one of Colombia’s most important maritime gateways.

The team carried out an assessment of the physical and chemical properties of dredged sediments alongside volumes and frequencies. These findings were fed into workshops with a broad group of stakeholders including: national ministries, local environmental authorities, ports, universities, military marine researchers and scientists from a national park just along the coast.

From this process, six conceptual designs emerged. Four addressed coastal erosion protection a real and urgent problem along the Department of Atlántico, where a combination of natural dynamics and impact of engineering works have disrupted natural sediment processes and left stretches of coastline exposed. The remaining two looked at soil enrichment and the production of construction materials.

Throughout the process, the project team emphasised that feasibility depends on context. “Distance is a key factor,” Pilar observes. “If the application site is too far from the dredging location, it simply isn’t economically viable. You have to look at it integrally incorporating the technical aspects, economic feasibility and community interests.”

A genuinely two-way exchange

The most important outcome of the project was not captured in five of the technical reports produced. It was this: knowledge exchange only works when it goes both ways.

“I want to really emphasise the two-way nature of this,” says Didi Gieling, Policy Officer at the Dutch Embassy in Bogotá. “From the beginning, I was genuinely impressed by the critical questions from all the counterparts, the scrutiny, the thinking-along.”

The collaboration between the Netherlands’ Government, Colombia’s Ministries of Environment and Transport and the National Department of Planning (DNP was formalised in a memorandum of understanding and has been running since 2017. This project, however brought the relationship to a different level.

Five training sessions were held over the course of the year, including two of them in Barranquilla. These brought together national policymakers, local experts, port operators and environmental authorities who deal with the Magdalena River every single day.

“One thing is sending a document,” Didi says. “Quite another is actually sitting down together and discussing it. Seeing what the interests are and which role other institutions need to play. Because you quickly realise it doesn’t stop at the ministries. So many other institutions have to come along for this to actually work.”

What comes next

The legal framework itself is still under development. The Ministry of Environment is preparing a decree that will lay the regulatory groundwork for reuse of dredging material, a process that is gaining traction and informed directly by the work the consortium has done. Full implementation on the ground will take time.

This year the Netherlands and Colombia mark 200 years of bilateral diplomatic relations and the project’s legacy is already taking shape with a new network of connections between Dutch and Colombian water professionals, researchers, ports, environmental institutions and businesses. As Colombia heads into presidential elections this June the network is built to last beyond government changes and will create opportunities for both Dutch expertise and Colombian industry alike.

Meanwhile, the sediment in the Magdalena River continues to move. The question is no longer whether Colombia can find a better use for it, but how quickly the country can build the systems to make that possible.

Please find here the project reports:

Final reports in English:
E1 – Key insights from the Netherlands on dredging (re)use approval [pdf]
E2 – Analysis Netherlands and other countries requirements for beneficial use of dredged sediments [pdf]
E3 – Assessment of the quality of dredged marine sediments in the port area of Barranquilla [pdf]
E4 – Procedural guidelines dredged marine sediments in Colombia [pdf]
E5 – Case study dredged sediments in Barranquilla [pdf]

Informes finales en español:
E1 – Información clave de los Países Bajos sobre (re)uso de sedimentos [pdf]
E2 – Análisis de requisitos de calidad uso sedimentos dragados en Países Bajos y otros países [pdf]
E3 – Evaluación de la calidad física y química de los sedimentos dragados en la zona portuaria de Barranquilla [pdf]
E4 – Directrices de procedimiento sedimentos marinos dragados en Colombia [pdf]
E5 – Estudio de caso aprovechamiento de sedimentos dragados en Barranquilla [pdf]