Client
Rijkswaterstaat
Location
IJmuiden, The Netherlands
IJmuiden Sea Lock
After almost 100 years in service, the IJmuiden Noordersluis needed replacing with a larger structure for modern shipping demands. The new OpenIJ sea lock - 500 metres long, 70 metres wide and 18 metres deep - is the largest sea lock in the world, securing maritime access for Amsterdam's port and protecting the wider Randstad from flooding for the next 100 years.
Financial Close
October 2015
Construction Period
5 years
Concession Period
26 years
Handback
2047
Client
Rijkswaterstaat
Location
IJmuiden, The Netherlands
Sponsor/Investor
Invesis and VolkerInfra PPP
Consortium
OpenIJ
Engineering Procurement and Construction
BAM Infra and Van Hattum en Blankevoort
Operations and Maintenance
BAM Infra and VolkerWessels Infra EPC
Capital Value
€457m
Partnering with Rijkswaterstaat to replace a century-old sea lock with the largest in the world
The Noordersluis at IJmuiden had served as the gateway between the North Sea and the Port of Amsterdam since 1929. By the early 2010s, it was approaching the end of its technical and economic life - and was no longer large enough to accommodate the growing scale of modern shipping. A new, significantly larger lock was urgently needed to protect the accessibility of Amsterdam's port and the broader North Sea Canal Area.
In 2015, Rijkswaterstaat awarded the DBFM contract to the OpenIJ consortium - comprising Invesis (50%) and VolkerInfra PPP (50%) - with construction delivered by a joint venture of BAM Infra and Van Hattum en Blankevoort. OpenIJ was selected on the basis of the Most Economically Advantageous Tender, achieving the maximum possible score on the DuboCalc sustainability component.
Construction commenced in January 2016 and the Availability Date was reached in August 2021, with the lock formally opened in January 2022. OpenIJ will maintain the lock until handback in 2047.
Engineering the world's largest sea lock with flood-proof gates, fish passages and low-vibration construction
The OpenIJ sea lock is a feat of engineering innovation. At 500 metres long, 70 metres wide and 18 metres deep, it is the largest sea lock in the world - built to withstand water levels up to 8.85 metres above NAP, providing primary flood defence for the Randstad for the next 100 years.
Both lock gates are flood-proof, going beyond the original Rijkswaterstaat specification. The caisson structures used for the lock heads are the size of a football field and 20 metres high, each sunk into the ground within three months. A fish passage through the middle wall enables year-round fish migration between salt and fresh water. Throughout construction, low-vibration methods protected the surrounding environment and shipping traffic on the North Sea Canal was maintained throughout the build.
Protecting the environment, enabling fish migration and creating employment across the IJmond region
- The control building at IJmuiden operates on a net-zero energy basis, powered entirely by solar panels installed as part of the project.
- OpenIJ achieved the maximum possible DuboCalc sustainability score in the tender, driven by environmental gains in concrete production - including an on-site concrete plant and concrete mortars with reduced cement clinker content.
- A fish passage through the middle wall of the sea lock allows fish to migrate freely between salt and fresh water throughout the year, protecting the ecological connectivity of the North Sea Canal.
- OpenIJ's Social Return programme employed 188 individuals from groups with a distance to the labour market, delivering 208 realised working years against a target of 200. 76% of participants progressed to paid employment and are no longer dependent on benefits.
- Low-vibration construction methods minimised noise and ground disturbance for communities along the North Sea Canal throughout the build.
