Coastal protection in Hörnum on Sylt; a causal chain?

The North Sea coast of the municipality of Hörnum in the south of Sylt has been subject to coastal erosion and retreat for centuries. After the construction of a holiday home development in the early 1960s, the need for coastal protection became acute. This case study describes the comprehensive protective measures implemented along the North Sea coast of Hörnum since 1962. It further discusses their respective functionality and morphological impacts, including the question of whether the measures constitute a causal chain.

This study concludes that the coastal protection measures in Hörnum were only in part sequentially and interdependently in their respective causes and therefore do not form a complete causal chain. Furthermore, measures to protect the Hörnum area from coastal erosion and flooding from the west would have become necessary even without the construction of the holiday home development. The implemented coastal protection measures have fulfilled their purpose. From today's perspective, the implemented measures represent the most efficient coastal protection solution. However, this goal could also have been achieved with other measures that interfere less with natural processes and development, but would have been significantly more expensive and would have resulted in an increasingly larger carbon footprint over time compared to the chosen solution.