Monitoring program of the coastal and estuarine waters
In an ongoing monitoring program of the coastal and estuarine waters in the south western part of the Netherlands, new discharge measurements have been carried out for evaluation of the flow patterns and long term flow changes in this important area. The region is historically known for the country’s continuing struggle with the sea, to provide safe living for its inhabitants. Therefore large waterworks have been built for protection of the islands and the remaining open waters are under strict watch. This region of Eastern and Western Scheldt is also both economically and environmentally important, because it links to major ports and has large fishing grounds coinciding with natural preserves. This large measurement campaign aims to support proper management of this complex region. The campaign consists of all 13-hour discharge measurements covering the tidal cycle at 11 key locations throughout the area. Measurements were carried out using our new vessel the Potvis. The huge variations in flow conditions, bottom depths ranging from dry falling plates to channels of over 40 meters deep, the varying natural environment and busy shipping fairways make this an exciting project in which care must be taken at every level of planning and performing these measurements. Discharges in excess of 60000 m3/s have been seen, of mixed tidal and river discharge. To reach some of the sites one has to sail over shallow water less than 2 meters deep at high water. The measurements are still ongoing and will be repeated every 5 years.