Hello everyone,

I have managed to read trough the comments in the forum and from what i have read i understood that the calculation that indicates the amount of water to be managed on site should be taken from the LEED V2009 SSc6.1 Credit. 

Meaning even if a project is setting out to achieve LEED V4.0 we use LEED v2009 calculation method : V.=P*Rv*A/12 

My question is, do we then also need to prove that the tanks are going to be emptied after each storm , using storm interval of 3 days as LEED v2009 used?

There is not a single line in LEED v4.0 guide about Drawdown rate, about emptying tanks before another storm event, ensuring full capacity after 72 hours or anything like that. Is it really okay just to calculate the amount of rain (volume) for the site and size the tanks, not caring about whether the soil can infiltrate fast enough? 

Best regards