Print Email Facebook Twitter Subaqueous and Subaerial Beach Changes after Implementation of a Mega Nourishment in Front of a Sea Dike Title Subaqueous and Subaerial Beach Changes after Implementation of a Mega Nourishment in Front of a Sea Dike Author Kroon, J. (TU Delft Coastal Engineering; Svašek Hydraulics) de Schipper, M.A. (TU Delft Coastal Engineering) de Vries, S. (TU Delft Coastal Engineering) Aarninkhof, S.G.J. (TU Delft Hydraulic Engineering) Department Hydraulic Engineering Date 2022 Abstract Sandy nourishments can provide additional sediment to the coastal system to maintain its recreational or safety function under rising sea levels. These nourishments can be implemented at sandy beach systems, but can also be used to reinforce gray coastal infrastructure (e.g., dams, dikes, seawalls). The Hondsbossche Dunes project is a combined shoreface, beach, and dune nourishment of 35 million m3 sand. The nourishment was built to replace the flood protection function of an old sea-dike while creating additional space for nature and recreation. This paper presents the evolution of this newly created sandy beach system in the first 5 years after implementation based on bathymetric and topographic surveys, acquired every three to six months. A significant coastline curvature is created by the nourishment leading to erosion in the central 7 km bordered by zones with accretion. However, over the five-year period, net volume losses from the project area were less than 5% of the initial nourished sand volume. The man-made cross-shore beach profile rapidly mimics the characteristics of adjacent beaches. The slope of the surfzone is adjusted within two winters to a similar slope. The initially wide beaches (i.e., up to 225 m) are reduced to about 100 m-wide. Simultaneously, the dune volume has increased and the dune foot migrated seaward at the entire nourished site, regardless of whether the subaqueous profile gained or lost sediment. Our results show that the Hondsbossche Dunes nourishment, built with a natural slope and wide beach, created a positive sediment balance in the dune for a prolonged period after placement. As such, natural forces in the years after implementation provided a significant contribution to the growth in dune volume and related safety against flooding. Subject nourishmentsbuilding with naturecoastline evolutiondune growthHondsbossche Dunescoastal morphology To reference this document use: http://resolver.tudelft.nl/uuid:e616b4b8-9588-4c7d-8693-42471bc302db DOI https://doi.org/10.3390/jmse10081152 ISSN 2077-1312 Source Journal of Marine Science and Engineering, 10 (8), 1-25 Part of collection Institutional Repository Document type journal article Rights © 2022 J. Kroon, M.A. de Schipper, S. de Vries, S.G.J. Aarninkhof Files PDF jmse_10_01152_v2.pdf 5.14 MB Close viewer /islandora/object/uuid:e616b4b8-9588-4c7d-8693-42471bc302db/datastream/OBJ/view