ZTIJ3: construction of the world's largest sea lock in IJmuiden

ZTIJ3: construction of the world's largest sea lock in IJmuiden

In order to accommodate the increasingly large sea-going vessels, work has been ongoing since 2016 in IJmuiden to build the largest sea lock in the world. The new lock will be 500 m long, 70 m wide and 18 m deep.

The new sea lock is being built to replace the Noordersluis. This lock is almost at the end of its service life. With this new sea lock, the Port of Amsterdam will remain accessible to the ever larger sea-going vessels. This is of great economic importance. The Port of Amsterdam is the fourth-largest port in Europe in terms of volume, and is linked to no less than 3 corridors.

Stop increasing salinization

Rijkswaterstaat is building a structure in the Binnenspuikanaal (Inner sluiceway) of the lock complex that will stop increasing salinization. An opening at the bottom of this structure will allow water to flow back to the sea via the pumping station/sluice complex. The fresh water is held back and remains in the North Sea Canal.

Studies show that a lock with dimensions of 500 m long, 70 m wide and 18 m deep is feasible, affordable and appropriate to the topography of the area. The studies looked at technical, spatial and nautical feasibility, the costs in terms of investment and maintenance, the expected impact on the environment, social costs and benefits, planning, risk and financial aspects.

The contractors’ consortium OpenIJ is building the new sea lock on behalf of Rijkswaterstaat. It is expected that the lock will be ready to receive shipping in early 2022.

Project period


European programme

Connecting Europe Facility

Project website

BAM PPP IJmuiden Sea Lock