Sustainability approach

The sustainability approach shown in the figure on page 24 has been used since the tender phase to visualise Boskalis’ sustainability approach. It outlines five steps – A to G – that organise the sustainability approach across the life cycle of the project. In the upper half, steps A, B and C belong to the design phase, during which the client and Boskalis focus on reducing carbon emissions through design choices and material strategy. In the lower half, steps D and E belong to the execution phase, where the team turns these choices into action through smarter logistics and the deployment of electric equipment. These choices regarding equipment were already made during the design phase. The figure makes a key principle very clear: sustainable execution begins long before construction starts.

Design phase (optimising design and preparing sustainable execution)

During the design phase, the client and Boskalis worked together to reduce emissions at the source. Step A focused on limiting the scope of both the river interventions related to the Water Framework Directive – the EU’s main law for protecting and improving the quality of surface water and groundwater – and the dyke design wherever possible. Step B focused on the local reuse of excavated materials, especially clay. Step C favours ground- and clay-based solutions over sheet piles wherever feasible, while ensuring that any required sheet piles are produced using scrap steel. These practical design decisions significantly influence the project’s environmental performance long before the first major transport movement takes place.

These early choices matter because Meandering Meuse is, to a large extent, an earthworks project. In total, approximately 5 million m³ of earthworks will be carried out, of which 1 million m3 will be used locally in the dyke reinforcement. At this scale, emissions are closely tied to material volumes, transport movements and equipment deployment. By addressing material use and technical solutions during the design phase, the client and Boskalis create the conditions for lower-impact execution later on.

Based on current project figures, the combined effect of design optimisations, more sustainable material choices, the deployment of electric equipment and compensation through nature development and energy generation (steps F and G) is expected to reduce emissions by more than 90% compared with the preferred alternative in the early design.

For the project, a material flow database has been developed to closely monitor the use and reuse of clay and soil, thereby supporting the sustainable execution of the project.

By excavating the agricultural land, the floodplains of the river are transformed into naturally occurring floodplain systems that consist of both reed marches and riparian forest. During the execution phase, several measures are conducted to stimulate the growth of these vegetation types, including afforestation practices and even reed transplantations. The future developed floodplain area provides both a climate-adaptive ecosystem with restored ecological value while also creating space for recreational purposes.

Execution phase

The lower half of the figure above shows how this strategy continues into the execution phase. Step D focuses on optimising clay logistics. Excavated clay and soil are transported to local depots or directly reused in other sections of the dyke reinforcement. This keeps material flows within the project area, reduces transport distances and limits the use of primary materials. In this sense, circularity is not treated as a separate ambition but is embedded in the daily production process.

Step E focuses on the use of zero-emission equipment. Excavation and transport are partly carried out using electric machinery, supported by a charging hub at a nearby wastewater treatment facility. Crucially, the project team developed this hub together with and for the client, who will become its owner after project completion. As a result, the facility serves not only the immediate needs of the works but also provides long-term capacity for more sustainable execution of future works.

The equipment deployed in the earthmoving works reflects the sustainable working method approach. Operations include electric excavators, electric trucks, electric loaders and the use of pontoons and barge transport for moving materials across the project area. Rather than waiting for a fully emission-free construction chain to become standard, the team combines currently available technologies into a practical working method. Over the full duration of the project, the deployment of electric equipment will account for around 10% of total equipment use.

Just as important as the measures themselves is the way the team monitors performance. During execution, Boskalis’ digitalisation team has developed a dashboard that tracks the deployment hours of equipment on the project. This gives the project team and the client direct insight into both carbon emissions and the use of electric equipment. By sharing these results with the client, the approach strengthens collaboration on sustainability and gives both parties a common basis for steering progress.

A joint effort

The project is still underway and will continue until 2030, which makes this cooperation all the more significant. The Meandering Meuse project is not presented as a finished success story from the comfort of hindsight, but as an ongoing application of its sustainability strategy within a live project. This gives the approach real value for the sector. It demonstrates not only what is technically possible, but also what it takes organisationally: early alignment, shared ambition, operational follow-through and a willingness to invest in enabling infrastructure together. A truly joint effort.