sicetaitsimple wrote:In any case I am willing to bet that if our friend installs his two tanks of 2000l with an overflow calibrated to 2l / s from 500l, never this one will be a day full!
They are not meant to be full. They are intended to temporarily "collect" a flow rate greater than 2 l / s. So the level can rise during the few minutes of the most violent part of a thunderstorm, then decrease on its own ...
It's like the basins we see now on all highway interchanges ...