Water management in urban areas is becoming increasingly complex, especially because of a rapid increase in impervious areas. There will also be a possible increase in extreme precipitation due to climate change. One of the most commonly implemented solutions to control flooding in urban areas is stormwater retention tanks where pluvial water is temporarily stored. Such devices usually serve twofold purpose, that is, ensure pluvial flood protection by storing water during the pick flow and decontaminate stormwater before releasing it into the natural environment during more common events. These two functions imply opposite management strategies; indeed in the decontamination mode, water needs to be stored at the beginning of the event whereas in the flood protection, the storage volume is kept empty for the peak flow. In order to optimise the use of these devices (i.e., increasing the amount of treated water while avoiding flooding), there is a need to improve fine-scale rainfall estimation, which is the most significant input, and to implement urban hydrological models.