I know little about the runoff subject but the local area here has long
been under the sort of rules you are referring to. One main reason for
this is due to a major river drying up that is mainly dependent on its
water being from vadose and/or alluvial zones.
Three friendly local cities that possibly could send you mature
information, building codes, inspection criteria and experience are:
Boulder, Colorado, USA
Louisville, Colorado, USA
Lafayette, Colorado, USA
Longmont, CO, USA