Can existing BUA be treated in lieu of treating new BUA?
Generally, yes. The BUA size to be treated must be greater than or equal to the area being added and both areas must drain to the same discharge point. Treatment trading is not allowed if the new BUA is vehicle related impervious and the existing BUA is rooftop and in other possible scenarios where it is determined that water quality benefits may be negatively impacted by the trade. Consult the land development engineer prior to submitting plans to ensure that the treatment trading will be allowed.
