Our future building owner is considering to install stormwater collection tank. Therefore we're trying to recommend the owner to comply with the LEED requirement.
As this site's previous imperviousness is greater than 50%, the option 2 would be selected.
According to my calculation, 25% of volume to be reduced is around 600 m3/day.
Is there a calculation method of storm water tank capacity to meet this credit?
In addition, I have another quick question regarding 2 year-24 hour design storm.
I understand that this number is from regional statistical data.
I got the following number from the Meteorological Administration Office;
"In 2007 and 2008, the greatest precipitation of this region during 24 hour was 1355 mm in June."
Therefore I used 1355 mm/day as a 2 year-24 hour design storm to calculate the runoff volume and 25% stormwater volume to be reduced.
Is this correct?
Amy Rider
Sustainability ManagerKEMA Services
161 thumbs up
January 21, 2011 - 2:45 pm
First of all, please double check your math. 600 cubic meters per day is an awful lot of water to have to store, divert for an alternative use and/or infiltrate.
Sizing your storage facility will depend on several factors including how you intend to use the water and the frequency of your rain events. Once you know your daily usage demands I recommend talking with a civil engineer and/or storage tank vendor for sizing assistance.
Your approach to determining the 24 hour design storm looks correct, but please note that if this value is higher than the 10 year annual average (i.e. unusually high) you should use the 10 year annual average instead (per page 5 of the 2009 ID&C Reference Guide).