New large sea lock

A new large sea lock is being constructed at the entrance of the North Sea Canal at IJmuiden that will provide access to the Amsterdam port region.

The new lock will be 500 metres long, 70 metres wide and 18 metres deep, making it the world’s largest sea lock. Construction began in January 2016 and the new lock will be available for shipping at the end of 2019. From then on, the port of Amsterdam will be accessible 24 hours a day.


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Project updates

The new sea lock - what's happening in April?

The most visible construction work at the new sea lock this month will be at the lock gate chambers of the outer head (number 2 in the picture) and the inner head (number 3 in the picture). For ships, the most noticeable thing in April will be the...
artist impression nieuwe zeesluis

The impact of the financial setbacks on the completion of the new sea lock is still unknown

At the end of last year, BAM and VolkerWessels reported disappointing financial results of the new sea lock project. The impact of this development on the completion date of the project is now being calculated and discussed.
caissonmethode nieuwe zeesluis

Three questions to Henk de Best of OpenIJ

OpenIJ is using the caisson method for installing the lock gate chambers into the new sea lock at IJmuiden. Because of the caisson method, the builders have to work at a depth of up to 24 metres below NAP (Dutch national chart datum in which zero...
sluisdeuren nieuwe zeesluis IJmuiden

Shipment of record-breaking lock gates

The new sea lock in IJmuiden will become the world's largest sea lock. No wonder that also its lock gates are colossal. In terms of length, they will be the largest lock gates in the world, but the gates of the Panama Canal locks are higher. The...

24/7 service technician present during obstruction of the IJmuiden Middle Lock

From 9 April 2018 06.00 LT to 4 May 2018 06.00 LT, the IJmuiden Middle Lock will be obstructed due to modifications carried out to the fendering system and the canal bed protection of the Middenbinnentoeleidingskanaal (the inner approach channel to...
selectieve onttrekking IJmuiden

Counteract salinisation in the North Sea Canal

There will soon be a much larger lock between the North Sea Canal and the North Sea. As a consequence, a much larger volume of seawater, i.e. salt water, will flow into the North Sea Canal each time a ship passes through the new lock....
Luchtfoto bouw nieuwe zeesluis februari 2018

The new sea lock - what's happening in March?

The new control building (no. 1 in the picture) is slowly beginning to take shape by now. The lock gate chambers (no. 2 in the picture) are also gaining in height. Also continuing this month are the concreting and anchoring operations of the lock...

Construction jargon

Reports on the construction of the New Sea Lock often use a number of technical terms, raising questions such as: What exactly is a sheet pile wall and what is a combi wall?
What is meant by the diaphragm method and the caisson method? What do these things look like?
We have listed the most used terms in a glossary with explanations and visual material.


Time to consider new possibilities Port of Amsterdam

These are the facts!

From the end of 2019, Port of Amsterdam will be home to a new, large sea lock. How big is this lock, and who will build it?

Animation about the sea lock

What will be the size of the lock, and what ships can pass through? This will all be clearly explained in this animation!

Now is the time to consider new opportunities!

A new sea lock - the largest in the world. How large, and what ships can pass through? You will find all the information you need right here.

 Dimensions ocean going vessels Port of Amsterdam

Dimensions of ocean-going vessels

The largest sea lock in the world! What ships will it be able to pass through?


Scheduled activities and obstructions

Some activities and obstructions have been scheduled in connection with the construction of the New Sea Lock. There are also scheduled activities and obstructions in connection with regular maintenance work to the North Lock and Middle Lock. An overview of the scheduled activities and obstructions of the North Lock and Middle Lock is given below.


Activities and obstructions in connection with the construction of the New Sea Lock

9 April 2018 06:00 unitl 4 May 2018 06:00
Obstruction Middle Lock IJmuiden
26 August 2016 until further notice Activities
Activities and measures in relation to the construction of the IJmuiden New Sea Lock

Activities and obstructions in connection with regular maintenance work to the North Lock and Middle Lock

18 juni 2018 10:00 until 18:00
Obstruction North Lock IJmuiden


Overview of prevailing Announcements >>


Direct contact with our expert

Andre Mulder

Divisie Havenmeester
Hoofd Operatie
Tel: +31 6 836 37 183

Read more about the new sea lock

Who is carrying out the work?

Commissioned by Rijkswaterstaat (Dutch Directorate-General for Public Works and Water Management), the new sea lock in IJmuiden will be built by the OpenIJ consortium of contractors during the next few years. The project is a collaborative venture of the Ministry of Infrastructure and the Environment, the Province of North Holland, the Municipality of Amsterdam, the Port of Amsterdam, and the Municipality of Velsen. The project is co-financed by the European Union’s TEN-T programme.

Want to stay informed?

The construction of the new sea lock can be followed on Facebook; Facebook you can also subscribe to our newsletter.

Do you have any questions, reports, complaints or comments regarding the construction work? Please contact Rijkswaterstaat, the Dutch Directorate-General for Public Works and Water Management, through the national Information number 0800 - 8002 (available free of charge daily from 6.00 am to 10.30 pm) or send an email to See the project page ‘building a new, large sea lock’ on the website of the Rijkswaterstaat IJmuiden..

When will the new sea lock be completed?

The world’s largest sea lock at IJmuiden provides access to the Amsterdam port area. Construction works will be carried out at the lock complex for the duration of the construction period. The parties involved in the construction of the new sea lock will do everything possible to ensure that shipping traffic can pass smoothly and safely.

1st half of 2016 Preparatory work including removal of the South Lock Island
Mid-2016 Re-routing of the inner approach channel to the Middle Lock & start of the construction of the new sea lock
2017 Contours of the new sea lock will become visible
Mid-2018 The gates of the new sea lock will be manoeuvred into place
End of 2018 Start testing of the new sea lock
2019 The new sea lock will be put into operational service

The completion of the new sea lock for shipping is scheduled for the end of 2019. The first ships may probably start to pass through the new sea lock during the operational test phase.

Why a new sea lock?

  • The North Lock will reach the end of its technical service life in 2029 and has become too small for today’s ever-larger seagoing vessels.
  • The New Sea Lock is tide-independent and can be used 24/7.
  • A new large sea lock allows new-generation larger vessels to pass through the North Sea Canal smoothly and safely.
  • With a larger lock, the port has the possibility to grow from today’s 90 million tons to 125 million tons of goods handled per year.