Together with the Maeslantkering and the dike widening Rozenburg, the Hartel barrier forms the Europoort barrier. This barrier functions fully automatically.
The Hartel barrier protects against high water by lowering two oval-shaped gates to the bottom. The barrier has slides that, when the barrier is open, hang 14 meters above sea level and can handle a water level of 3 meters above sea level. The Hartel barrier has two passageways of 49 and 98 meters wide and lifting cylinders which, when the barrier was completed, were the largest in Europe.
The Hartel Barrier has the same closing criteria as the Maeslant Barrier and therefore closes in principle at the same time as the Maeslant Barrier . This happens at Rotterdam a water level of more than three meters above sea level is predicted at Dordrecht and a water level of more than 2.9 meters above sea level. The closure – and also the decision on this – is fully automatic. Nevertheless, in case of expected high water, an operational team from Rijkswaterstaat is always present to monitor the automatic process. The Hartel Barrier and the Maeslant Barrier have been closed twice by the automatic decision and support system (BOS) so far, in 2007 and during the New Year’s storm in 2018. Due to climate change, this will probably occur more often in the future, according to calculations 1 to 2 times every 10 years.