VESSEL REVIEW | Dutch operator's new electric dredger built for inland waters
Netherlands-based engineering specialist the Dekker Group has taken delivery of a new electric cutter suction dredger (CSD) built by local company De Klop.
The CSD is equipped with a submersible pump and pole truck as standard and is built under Bureau Veritas class for coastal waters. De Klop said the CSD was built entirely in the Netherlands and was already in an advanced stage of completion at the time of the sale to Dekker.
“It is a fully electric, standardised, and demountable CSD, designed to be built on stock rather than for a specific end user,” André Kik, Naval Architect and Co-Owner of De Klop, told Baird Maritime. “This approach enables short delivery times while maintaining high technical standards and flexibility for final configuration.
Adaptable to various soil types and depths
The first CSD in the Dekker fleet has been engineered for emission-free dredging of a wide range of soil types including silt, sand, and gravel.
”Its power supply concept is highly flexible and can be sourced from the electrical grid or from external energy systems such as fuel cell generators or generator sets running on methanol, LNG, or diesel,” added De Klop Co-Owner and Dredging Specialist Marcel Boor. “This makes the CSD easily adaptable to local energy availability and future fuel transitions.”
Dekker had requested for a robust and flexible production asset that could operate reliably across multiple projects under increasingly stringent environmental and regulatory conditions.
“First and foremost, the vessel had to be fully electric and emission-free in operation,” said Boor. “This was a fundamental requirement, driven by Dekker’s ambition to work in environmentally sensitive river systems and urban areas, and to remain compliant with both current and future emission legislation. From a builder’s perspective, this meant designing a dredger that could operate entirely without onboard combustion engines or hydraulics, while still delivering predictable and high production rates.”
The energy concept had to allow power supply from shore but also be compatible with alternative external power sources such as generator sets or future energy technologies. This requirement translated into a vessel architecture that is fuel-flexible and prepared for technological developments over its operational lifetime.
“Another key element of the brief was performance across a wide operating window,” said Kik. “The dredger had to be capable of handling varying soil types—from fine sediments to sand and gravel—while maintaining stable production.
“In addition, Dekker explicitly required the vessel to be adaptable for greater dredging depths, without the need for fundamental redesign. This placed strong emphasis on pump selection, cutter power, structural margins, and the scalability of the overall system.”
Can be upgraded with greater capacities without extensive rebuilding
The design allows straightforward upgrading to greater dredging depths without compromising efficiency or reliability. The new Dekker dredger itself will be modified to operate at significantly increased dredging depths.
“Dekker required a dredger that functions as a true process machine, where cutter power, pump characteristics, pipeline diameter, and swing and step behaviour are carefully balanced. For us, this meant focusing not only on individual components, but on system integration and process optimisation to ensure consistent performance under real project conditions.”
Modular assembly for each of servicing and deployment
Practical operability was another important requirement. The vessel had to be demountable and logistically efficient, allowing transport and mobilisation to inland project locations with minimal disruption.
Assembly also had to be safe and straightforward, preferably without underwater connections, reducing risk during installation and maintenance. This requirement directly influenced the modular design philosophy and interface engineering.
“Finally, Dekker placed strong emphasis on maintainability and lifecycle costs,” Boor told Baird Maritime. “The dredger had to be accessible, service-friendly, and designed with long-term ownership in mind. This required close involvement of service and maintenance expertise during the engineering phase, ensuring that maintenance is designed in rather than added later.
“In summary, the brief called for a dredger that combines zero-emission operation, scalable performance, modular construction, and long-term adaptability. The CSD was therefore not conceived as a project-specific solution, but as a platform that enables Dekker to deliver complex river and area development projects reliably, sustainably, and efficiently.”
Earmarked for waterways maintenance under Dutch Government supervision
The fully electric CSD will be used for the accelerated construction of a flowing side channel (nevengeul) in the Willemspolder along the Waal, a project commissioned by Rijkswaterstaat as part of the national effort to meet the European Water Framework Directive objectives.
Originally planned for completion in 2032, the nevengeul will now be fully operational by the end of 2027. This acceleration is critical for improving water quality and ecological conditions in the Waal river system, while simultaneously contributing to long-term river resilience.
“From a technical perspective, the CSD is particularly well suited to this project,” added Kik. “Starting in the spring of 2026, the dredger will be used to excavate approximately 1.6 million cubic metres (57 million cubic feet) of sand under controlled and emission-free conditions. Its fully electric drive, powered from shore or external power sources, eliminates local emissions and significantly reduces noise, making it ideal for use in ecologically sensitive floodplain environments.”
As the dredging process itself demands a high degree of control and reliability, the CSD is designed as an integrated process machine, in which cutter power, submerged pump performance, pipeline configuration, and swing and step behaviour are balanced. This would allow Dekker to shape the side channel with high accuracy, ensuring hydraulic functionality while preserving surrounding natural structures.
The dredger’s ability to handle varying soil types – ranging from fine sediments to sand – will meanwhile ensure stable production throughout the project.
“A key technical advantage for this project is the scalability of the dredger,” said Kik. “It has been adapted for increased dredging depths, enabling efficient excavation across the full profile of the new side channel without compromising performance or operational safety. This adaptability reduces the need for additional equipment and contributes to a streamlined execution strategy.”
Novel solution for river dredging
For De Klop, the challenge in the work on the CSD was related to the fact that the company was introducing a new standard dredger to the market.
“As De Klop is a relatively small company operating in a market dominated by several well-established manufacturers, it was clear that a direct, head-on competition strategy would not be effective,” Boor told Baird Maritime. “Instead, we deliberately set out to develop something different—an innovative concept that would clearly distinguish itself from existing solutions.
Standard platform with custom features
Kik said that because De Klop was not constrained by legacy technologies or existing standards, this allowed the company to fully rethink the concept from the ground up.
“The most difficult decision was determining the target market for the dredger. Ultimately, we chose to focus on the high-end segment. At the same time, we made a conscious decision to develop a sustainable concept, with no combustion engines or hydraulic systems on board. Safety and low operating costs were also central design principles.
“We were fully aware that this approach would position us in a niche market, but this was a deliberate choice. Moreover, we strongly believe that this segment will continue to grow in the future.”
De Klop’s plan was to incorporate the latest state-of-the-art technology. Kik remarked that the company therefore began work on the dredger by identifying the most advanced components available, all the while being mindful that a CSD is a process machine where overall performance depends on the interaction between all systems.
“One of the main challenges was finding the right balance between developing a standardised product—offering significant cost advantages, shorter delivery times through stock building, and faster spare-parts availability—while still achieving excellent performance under a wide range of operating conditions.
“Scalability was another key requirement. We deliberately selected a submerged pump configuration, enabling dredging at greater depths while ensuring more stable and efficient performance in all conditions.
In addition, the builder opted for a relatively higher cutter power. For every design decision, the additional investment was carefully weighed against the performance benefits.
“Another critical challenge was achieving the optimal balance between cutter power, pump characteristics, pipeline diameter, and swing and step behaviour. Thanks to our team of dredging technologists with extensive practical knowledge, we were able to determine an optimal configuration.”
“From a regulatory perspective, we chose to build the vessel under the class of Bureau Veritas, the classification society with the most extensive experience in dredging vessels,” said Boor. “Given the high level of innovation incorporated into the design, this involved many in-depth discussions with Bureau Veritas to arrive at robust and compliant solutions that would allow the vessel to be successfully classed.”
Flexibility allowing for construction both onshore and in the water
Partly because this is the first vessel of its kind, multiple risks also became evident during its construction, as Boor explained.
“An important aspect of this project was that the vessel was built in stock, without a specific end customer at the time of construction. This required us to focus on optimisation rather than speed, allowing design choices, construction details, and system integration to be refined where necessary to achieve the best possible overall result.
The vessel was designed with clearly defined tolerances, though in practice, it always remains to be seen how closely the tolerances of supplied components match the assumptions made during engineering.
“At several points, minor adjustments proved necessary. Because the critical interfaces had been identified early in the design phase, we were able to anticipate this by using modular and independent components that could be adjusted easily without compromising the overall concept or schedule.”
The dredger was built entirely in the Netherlands. Most components and systems were sourced locally, primarily from suppliers in the Sliedrecht region, while larger hull sections such as the pontoons were fabricated in the northern part of the country. In the build team’s view, this local supply chain contributed to short communication lines, fast problem-solving, and consistent quality control throughout the build process.
“During the engineering phase, extensive attention was given to manufacturability and maintainability,” Kik remarked. “The design team worked closely with the construction team, ensuring that practical experience directly influenced engineering decisions. Because the people involved in building the vessel were also closely engaged in its development, potential problems were addressed at an early stage.”
The assembly of the demountable dredger was carried out on the quay. However, the vessel was deliberately designed in such a way that full assembly can also take place afloat.
“A unique aspect of this design is that there are no structural or system connections below the waterline. This allows assembly to be carried out safely, while eliminating the risk of leakage caused by poorly accessible or improperly sealed underwater connections.”
Identifying and resolving issues as they arise
The development and construction of the CSD provided valuable insights to De Klop, particularly because it was the first standard CSD of its kind.
“The main challenges were not found in the technical complexity itself, but in translating a new design into a reproducible and reliable build,” Kik told Baird Maritime, “From the outset, standardisation proved to be a crucial design principle. By defining interfaces, layouts, and system boundaries early in the engineering phase, changes during construction could be absorbed without undermining the overall concept, confirming the long-term value of a well-defined standard platform.”
Kik added that although the vessel was engineered with clearly specified tolerances, practical experience showed that variations in supplied components are inevitable, which reinforced the importance of identifying critical interfaces early and designing adjustability into those areas. By deliberately applying modular and independent components where tolerances were most critical, minor deviations could be corrected efficiently, preventing knock-on effects elsewhere in the system.
The close integration between engineering and construction also contributed to the smooth execution of the project.
“Because the people responsible for building the vessel were also involved in its development, practical considerations such as manufacturability, accessibility, and maintenance were embedded in the design from the beginning,” said Kik. “This significantly reduced start-up issues and ensured that potential problems were identified and resolved at an early stage.”
The De Klop build team said that, as with any first standard vessel, the CSD required additional engineering effort and conservative design margins in certain areas.
In practice, this proved to be a sensible approach, providing the flexibility needed during construction and commissioning. These experiences now form a foundation for work on the company’s future vessels, where proven behaviour will allow further optimisation and refinement.
“Finally, the project confirmed that standardisation does not imply rigidity,” Boor remarked. “While the CSD was developed as a standard dredger, the design retains a high degree of adaptability. Upgrades such as increased dredging depth or alternative power supply concepts can be implemented without fundamental redesign.
Boor added that this balance between a robust standard and built-in flexibility has proven to be essential in developing a future-proof dredging platform.
