Maeslant Barrier

The Maeslant Barrier is a marvel of engineering and a testament to the Netherlands’ commitment to flood protection. No other flood barrier in the world has larger moving parts than the Maeslant Barrier.

It is a vital part of the Delta Works and is designed to withstand a storm surge of 5 m above NAP (the NAP level of zero is about equal to the average sea level in the North Sea).

The Maeslant Barrier is located near Hook of Holland. It was built between 1991 and 1997 and is fully automated. Together with the Hartel Barrier and the extended Rozenburg Dyke, it forms the Europoort Barrier. The Maeslant Barrier is a forward flood surge barrier, which means that it takes the full brunt of the tidal surge from the sea. 

This helps to protect the residents of the province of Zuid-Holland from flooding.

Facts and figures about the Maeslant Barrier

210 m

is the width of each door of the Maeslant storm surge barrier

The Maeslant Barrier:

  • was closed for the first time in 2007
  • has 2 gates, each 210 m wide, 22 m high and 15 m deep. When the barrier closes, the gates fill with water and sink to the bottom within 2 hours
  • operates with ball-and-socket joints, each of which is 10 m in diameter and weighs 680 tonnes

The construction

The Maeslant Barrier was not a part of the original Delta Plan, but its design is just as ingenious and massive as the other structures of the Delta Works. Prior to its construction, an independent committee examined four options for the barrier in close consultation with Rijkswaterstaat, the municipality of Rotterdam and the water authority. 

The committee considered factors such as the cost, the time to build, the impact on the economy and how well the barrier would blend into the landscape.

Rijkswaterstaat’s tasks

Rijkswaterstaat manages and maintains the Maeslant Barrier. We use a specially developed model to calculate the risk of the barrier not closing. Based on these calculations, we test, inspect, repair and replace parts as needed.

The Maeslant Barrier closes fully automatically

Closing the barrier

The Maeslant Barrier closes fully automatically when the water level is predicted to rise to more than three metres above NAP near Rotterdam or more than 2.9 m above NAP near Dordrecht. In principle, no human intervention is required. 

However, if flooding is expected, an operational team from Rijkswaterstaat is always on hand to monitor the automatic process and to intervene manually if necessary.

Plan your visit to the Maeslant Barrier

If you would like to see the Maeslant Barrier in action, visit the Keringhuis Water Management Information Centre. The Watersnoodmuseum at Ouwerkerk is also worth a visit. This museum is dedicated to the North Sea flood of 1953 and the Delta Works.

You can learn more about these events, the strengthening of the dikes and the repair work that had been done.