groundwater flow at TAW altitude

This groundwater map shows the position/height of the phreatic groundwater and the predominant flow direction in relation to the Second General Water Passing (TAW), the topographical reference plane in Flanders. This was drawn up on the basis of the existing gauge network of the city of Antwerp. In places where groundwater data were missing, additional monitoring tubes were installed as part of this study. As with the groundwater map (m-mv), additional data from probes from the Flanders Subsurface Database were used for this purpose. In the context of rainwater policy and the principles of optimal separation with the aim of promoting the natural runoff and infiltration of rainwater, it is important to have an insight into the soil condition and infiltration sensitivity of the upper soil layer in Antwerp. In this way, the integration of water management into urban design can be controlled more effectively and efficiently, as well as the localisation of infiltration-prone areas for future construction projects. For example, city authorities regularly receive questions from contractors, architects and design offices about the possibility of infiltration on a particular plot. This information is also important in the design and implementation of public urban renewal works. The layout of geohydrological maps can contribute to a better alignment between spatial planning, public space design, green management and water management. It is quite possible to save costs by combining multiple management aspects with the construction of green-blue structures: tackling flooding, combating soil desiccation, developing more urban nature and biodiversity. Finally, these data are used as substantiation in the preparation of the rainwater plan; a plan indicating at district level how much infiltration and/or buffer capacity is desirable and in which forms (e.g. collective wadi, canal or pond). The contract concerns the preparation of four geohydrological maps, in particular: a soil map, a groundwater map (meter - ground level) with an annual average depth of the phreatic groundwater table below street level, a groundwater map with annual average levels relative to the topographic reference level (meter -/+ TAW) and an infiltration map of the Antwerp region. The study is part of the characterisation of the subsurface of Antwerp with a view to the localisation of infiltration-prone areas for future construction projects. These maps describe the entire regionthe territory of Antwerp (city of Antwerp with its 9 districts and submunicipalities), with the exception of the Antwerp port area. For the right bank of the Antwerp port area, the possibilities of rainwater infiltration and buffering have already been investigated (What about rainwater in the Antwerp port area?, IMDC iov Port of Antwerp and Alfaport, 2013). In function of the calibration and calculation of groundwater and groundwater data, it was important to integrate the port area into the model area. . The study area is bounded to the north, east, south and west respectively by the national border and municipalities of Berendrecht, Deurne, HobokenStabroek, Kapellen, Brasschaat, Schoten Wijnegem, Wommelgem, Borsbeek, Mortsel, Edegem, Aartselaar, Hemiksem and LinkeroeverZwijndrecht.