Input database for the Bretschneider wave calculations for narrow river areas : in preparation for the WTI-2017 production runs

In this report the method of the determination of hydraulic boundary conditions for WTI-2017 for narrow river areas in the Netherlands has been described. The following regions were studied: - Meuse (in Dutch: Maas) - Rhine Branches (in Dutch: Rijntakken) - Vecht-Ussel delta - Mouth of the Rhine-Meuse (in Dutch: Rijn-Maas-monding, or simply RMM) In the narrow parts of these river areas, the hydraulic boundary conditions for WTI-2017 will be determined with the empirical Bretschneider wave growth curves. The Bretschneider curves need various inputs: - Wind velocity; - Effective fetch; - Representative water depth. These inputs have to be determined for a large number of locations in the regions of interest and for 16 wind directions. Use is made of two tools and Baseline schematizations of the regions to calculate the effective fetch and representative water depth. The fetches are calculated from the river contours, following the crest height (in Dutch: buiten kruinlijn) of the primary water defence of a dike ring. As a starting point dry areas and obstacles were not taken into account in the fetch determination. Various checks on the input for the Bretschneider production runs and the results of the Bretschneider calculations were performed to make sure that correct results are delivered for the WTI-2017 production runs. The results of the Bretschneider runs have been stored in a structured matlab format and a *.kmz file to be used in the determination of HR2017 and for further processing in follow-up studies.