What is Delta21?

Delta21 is an innovative project in the South Holland Delta that combines three major challenges into one smart system. The challenges are energy security, water safety, and nature restoration. At the heart of the plan is a reservoir of approximately 20 square kilometers that functions as a natural battery. This allows sustainable energy to be temporarily stored and returned when needed. At the same time, it protects against extremely high water levels by pumping excess river water into the sea. By permanently opening the Haringvliet locks, the salt tide will also return, creating a unique brackish water area that provides space for nature restoration and fish migration.

Collaboration

The cooperative brings together parties that would not normally sit down at the same table, such as large companies and energy cooperatives. Together, we are working on solutions for the three major social challenges. Ballast Nedam contributes its expertise in complex infrastructure and hydraulic engineering to make this unique solution possible. Together with partners such as Van Oord, Boskalis, BAM Infra, and various energy cooperatives, we are working on a project that is at least as ambitious as the Delta Works—but for today's challenges.

Look ahead

The Ministry of Climate and Green Growth is preparing a social cost-benefit analysis. Regional parties such as the Province of South Holland, water boards, and municipalities are also involved in this. This analysis will provide insight into what Delta21 will deliver for society as a whole. If everything goes according to plan, Delta21 will be running at full capacity by the mid-2030s.