Netherlands Journal of Geosciences — Geologie en Mijnbouw |96 – 4 | 293–317 | 2017 doi:10.1017/njg.2017.34 Dynamic preservation of Texel Inlet, the Netherlands: understanding the interaction of an ebb-tidal delta with its adjacent coast Edwin P.L. Elias1,∗ & Ad J.F. van der Spek2 1 Deltares USA, 8601 Georgia Ave., Silver Spring, MD 20910, USA 2 Deltares, P.O. Box 177, 2600 MH Delft, the Netherlands ∗ Corresponding author: Email:
[email protected] Manuscript received: 6 March 2017, accepted: 26 September 2017 Abstract Tidal inlets and the associated ebb-tidal deltas can significantly impact the coastal sediment budget due to their ability to store or release large quantities of sand. Nearly 300 million m3 (mcm) of sediments were eroded from Texel Inlet’s ebb-tidal delta and the adjacent coasts following the closure of the Zuiderzee in 1932. This erosion continues even today as a net loss of 77 mcm was observed between 1986 and 2015. To compensate, over 30 mcm of sand has been placed on the adjacent coastlines since 1990, making maintenance of these beaches the most intensive of the entire Dutch coastal system. Highly frequent and detailed observations of both the hydrodynamics and morphodynamics of Texel Inlet have resulted in a unique dataset of this largest inlet of the Wadden Sea, providing an opportunity to investigate inlet sediment dynamics under the influence of anthropogenic pressure. By linking detailed measurements of bathymetric change to direct observations of processes we were able to unravel the various components that have contributed to the supply of sediment to the basin, and develop a four-stage conceptual model describing the multi-decadal adaptation of the ebb-tidal delta.