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Shore nourishments have been carried out worldwide for several decades and are nowadays seen as an almost routine coastal protection measure. However, the recent paradigm shift to an Integrated Coastal Zone Management (ICZM) and to an Ecosystem Approach to Management (EAM) requires new concepts, models and tools for the implementation of more sustainable and environmentally friendly shore nourishments. The interdisciplinary research project STENCIL aimed at making a first step towards the long-term goal of es- tablishing an EAM for shore nourishments. Joining the expertise of coastal engineers, ge- ologists and ecologists, the project has provided improved tools and methods for the pre- diction of coastal hydro- and morphodynamics and related ecological impacts. A combination of field measurements, laboratory experiments and analytical as well as nu- merical models has resulted in valuable new data sets. This paper summarizes the most important scientific outcomes of the project, like the use of Artificial Neural Networks (ANN) to overcome weaknesses of current hydrodynamic numerical modelling tools; the analysis and interpretation of long-term beach profile data using a newly developed data- driven methodology, allowing for a better assessment of the morphological development of beach and foreshore nourishments; the improvement of a sediment transport model for mixed sand based on a unique large-scale experiment in the Large Wave Flume (GWK) carried out within the project; an impact assessment of dredging activities around Sylt, based on six extensive survey cruises at the sand extraction sites “Westerland II & III”; and the application of the hydrotoxicology method for the same study site to determine the influence of sand extraction on chemical-physical water quality parameters and the ecotox- icological potential. These interdisciplinary project results were combined with a compre- hensive state of the art review in a SWOT analysis for shore nourishments, which

Shore nourishments have been carried out worldwide for several decades and are nowadays seen as an almost routine coastal protection measure. However, the recent paradigm shift to an Integrated Coastal Zone Management (ICZM) and to an Ecosystem Approach to Management (EAM) requires new concepts, models and tools for the implementation of more sustainable and environmentally friendly shore nourishments. The interdisciplinary research project STENCIL aimed at making a first step towards the long-term goal of es- tablishing an EAM for shore nourishments. Joining the expertise of coastal engineers, ge- ologists and ecologists, the project has provided improved tools and methods for the pre- diction of coastal hydro- and morphodynamics and related ecological impacts. A combination of field measurements, laboratory experiments and analytical as well as nu- merical models has resulted in valuable new data sets. This paper summarizes the most important scientific outcomes of the project, like the use of Artificial Neural Networks (ANN) to overcome weaknesses of current hydrodynamic numerical modelling tools; the analysis and interpretation of long-term beach profile data using a newly developed data- driven methodology, allowing for a better assessment of the morphological development of beach and foreshore nourishments; the improvement of a sediment transport model for mixed sand based on a unique large-scale experiment in the Large Wave Flume (GWK) carried out within the project; an impact assessment of dredging activities around Sylt, based on six extensive survey cruises at the sand extraction sites “Westerland II & III”; and the application of the hydrotoxicology method for the same study site to determine the influence of sand extraction on chemical-physical water quality parameters and the ecotox- icological potential. These interdisciplinary project results were combined with a compre- hensive state of the art review in a SWOT analysis for shore nourishments, which

Die SWOT-Analyse zeigt, dass jedes Verfahren für die Materialentnahme und die Aufspülung eine Reihe von Vor- und Nachteilen mit sich bringt, die der Anwender gegeneinander abwägen muss. Mit weiteren Forschungsergebnissen, v.a. hinsichtlich der langfristigen ökologischen und morphologischen Auswirkungen der Verfahren, könnten einige der potenziellen Chancen und Risiken zu bekannten und absehbaren Stärken bzw. Schwächen werden. Bis dahin muss der Anwender unter Berücksichtigung aller Faktoren ein Verfahren auswählen, das für den geplanten Anwendungsfall geeignet ist und bei dem die Risiken für die Region vertretbar sind. Dabei muss jedoch beachtet werden, dass viele bisher unbekannte biologische Prozesse möglicherweise weitere Auswirkungen auf das Küstenökosystem haben könnten. Daher sind Eingriffe in die Küstenumwelt immer mit gewissen Risiken für das Ökosystem und den Menschen verbunden und sollten nur dann erfolgen, wenn sie unter Abwägung der wesentlich beeinflussten marinen und terrestrischen Kompartimente und nach Diskussion und Priorisierung der primären Schutzziele (Lebens-, Natur- und Wirtschaftsraum) unbedingt erforderlich sind.

Die SWOT-Analyse zeigt, dass jedes Verfahren für die Materialentnahme und die Aufspülung eine Reihe von Vor- und Nachteilen mit sich bringt, die der Anwender gegeneinander abwägen muss. Mit weiteren Forschungsergebnissen, v.a. hinsichtlich der langfristigen ökologischen und morphologischen Auswirkungen der Verfahren, könnten einige der potenziellen Chancen und Risiken zu bekannten und absehbaren Stärken bzw. Schwächen werden. Bis dahin muss der Anwender unter Berücksichtigung aller Faktoren ein Verfahren auswählen, das für den geplanten Anwendungsfall geeignet ist und bei dem die Risiken für die Region vertretbar sind. Dabei muss jedoch beachtet werden, dass viele bisher unbekannte biologische Prozesse möglicherweise weitere Auswirkungen auf das Küstenökosystem haben könnten. Daher sind Eingriffe in die Küstenumwelt immer mit gewissen Risiken für das Ökosystem und den Menschen verbunden und sollten nur dann erfolgen, wenn sie unter Abwägung der wesentlich beeinflussten marinen und terrestrischen Kompartimente und nach Diskussion und Priorisierung der primären Schutzziele (Lebens-, Natur- und Wirtschaftsraum) unbedingt erforderlich sind.

Dieses Dokument wurde im Rahmen des Forschungsvorhabens STENCIL erstellt, das unter dem Förderkennzeichen 03F0761A-D vom Bundesministerium für Bildung und Forschung gefördert wurde.

Shore nourishments are regarded as an almost routine coastal protection measure and have been carried out worldwide for several decades. Recent studies generally conclude that “soft” coastal protection measures are an effective option for a sustainable coastal management. However, more research on economic sustainability, species-specific habitat demands and availability of sand deposits is required. Nowadays, the recent paradigm shifts to concepts like the Integrated Coastal Zone Management (ICZM) and the Ecosystem Approach to Management (EAM). For the German Wadden Sea these management objectives are an important issue of the “Wattenmeerstrategie 2100” , a political strategy report that demands an adaption against the global change and the expected sea-level rise up to the year 2100. Hence, also new concepts and tools for the implementation of more sustainable, effective and environment-friendly shore nourishments are needed. The research project STENCIL joins the expertise of coastal engineers, geologists, biologists and toxicologists in order to make a first step towards the long-term goal of establishing an ICZM and EAM for shore nourishments in the German Wadden Sea. The project focuses on providing improved tools, models and methods for the prediction of coastal hydro- and morphodynamics. Furthermore, the impact of dredging and dumping activities on benthic habitats and their natural regeneration potentials will be evaluated. Since these impacts are still widely uninvestigated, monitoring of dredging areas and the surrounding sites using hydroacoustic devices, aerial photos and sediment samples for grain-size and benthos analysis remains of high importance. In order to develop standardized operative observation methods, analysis and decision-supporting tools, an implementation of field measurements, laboratory experiments as well as conceptual and numerical models is planned. These combined approaches will result in valuable data sets for habitat evaluation

Shore nourishments are regarded as an almost routine coastal protection measure and have been carried out worldwide for several decades. Recent studies generally conclude that “soft” coastal protection measures are an effective option for a sustainable coastal management. However, more research on economic sustainability, species-specific habitat demands and availability of sand deposits is required. Nowadays, the recent paradigm shifts to concepts like the Integrated Coastal Zone Management (ICZM) and the Ecosystem Approach to Management (EAM). For the German Wadden Sea these management objectives are an important issue of the “Wattenmeerstrategie 2100” , a political strategy report that demands an adaption against the global change and the expected sea-level rise up to the year 2100. Hence, also new concepts and tools for the implementation of more sustainable, effective and environment-friendly shore nourishments are needed. The research project STENCIL joins the expertise of coastal engineers, geologists, biologists and toxicologists in order to make a first step towards the long-term goal of establishing an ICZM and EAM for shore nourishments in the German Wadden Sea. The project focuses on providing improved tools, models and methods for the prediction of coastal hydro- and morphodynamics. Furthermore, the impact of dredging and dumping activities on benthic habitats and their natural regeneration potentials will be evaluated. Since these impacts are still widely uninvestigated, monitoring of dredging areas and the surrounding sites using hydroacoustic devices, aerial photos and sediment samples for grain-size and benthos analysis remains of high importance. In order to develop standardized operative observation methods, analysis and decision-supporting tools, an implementation of field measurements, laboratory experiments as well as conceptual and numerical models is planned. These combined approaches will result in valuable data sets for habitat evaluation