Storm surge barrier Ramspol is an inflatable dam that closes off the Zwarte Meer of the Ketelmeer during high water and thus guarantees the safety of the hinterland. The barrier was opened in December 2002. The Ramspolkering consists of three bellows, each 80 meters long. The height of the bellows weir when it is filled with air is 10 meters. The barrier has a capacity of 21 million liters and closes at a water level of NAP + 0.50 meters and a strong northwest wind. The Ramspol barrier was last closed on March 12, 2020 and is being tested once a year.