A new report from the Danish Coastal Directorate shows that in the future, the water level must be higher in half of Denmark to be considered a storm surge. This change may make it more difficult to receive compensation for flooding in certain areas that were previously declared as storm surge areas. According to Thorsten Piontkowitz, head of department at the Danish Coastal Directorate, the increase in requirements is especially significant in the southern part of the country. However, at many measuring stations, the values have only changed by a few centimeters. The report, which is published every five years but this time is delayed, includes data from 69 measuring stations, and at 33 of these stations, there has been an increase in the value for a 20-year event. Examples of places with this increase include Faaborg, Hesnæs on Falster, and Sønderborg.
The southern part of Denmark has experienced the largest increase in water level, which is attributed to the historically violent storm surge in October 2023, referred to as a 100-year event. Piontkowitz notes that even though the event was exceptional, sea levels are expected to continue to rise in general. When the sea exceeds normal water levels due to severe weather and high tides, it is the Nature Damage Council (Naturskaderådet) that assesses whether it is a storm surge. This assessment is based on data from the high water statistics. According to Poul Jensen, head of secretariat at the Nature Damage Council, changes in the statistics will mean that some areas will find it harder to receive compensation, while others will find it easier. He highlights that it will be more difficult to receive compensation in areas where the water level for a 20-year event has risen.
There have been several episodes of storm surges in recent years, including in 2006, 2013, October 2023, and December 2023. The event in October 2023 was particularly notable with extreme water levels in Gedser, Kolding, and Aabenraa. These extreme levels have no effect on future compensation possibilities in these areas, says Jensen. He adds that there are also areas where the level for a 20-year event has decreased, such as Copenhagen, Hornbæk, parts of the Great Belt, and the southern part of the Baltic Sea.
The report from the Danish Coastal Directorate was supposed to be completed at the beginning of the year but was delayed due to the storm surge events in October and December 2023. Piontkowitz emphasizes that it was important to include these events in the new calculations.