Provisionally secured areas for HW relief/retention

Provisionally secured areas for HW relief/retention are areas intended for the construction of flood polders. Flood polders are special containments surrounded by dikes with low damage potentials. In the event of very large flood events, water is systematically discharged into a flood polder, held there and released again after the flood has elapsed. This reduces the tip of the flood drain below the flood pole. In order for the retention areas to be flooded if necessary, they must be close to the river. Often these are former or still existing flooding areas, which were previously flooded even in small flooding events.