Dear all,
We are currently wondering what is th ruling in the case of an underground parking being below a green space area, which we would tend to account for in the pervious area contribution for post-development runoff. Considering the soil layer might be more than 2m thick is it acceptable?
Many thanks,
Aymeric
Michael DeVuono
Regional Stormwater LeaderArcadis North America
LEEDuser Expert
186 thumbs up
November 6, 2015 - 6:22 am
There is no "ruling." You can build whatever your heart desires, but you need to manage the runoff from it.
If your design is such that no rainfall ever touched your parking area, or runs down into it (trench drain control at the entrance), I'd say use the lawn as your cover type for your calcs.