Detention Pond Design in Metro Atlanta: GSMM Sizing Criteria, Costs, and Approval Timelines
In Metro Atlanta, a detention pond is sized against four separate criteria in the Georgia Stormwater Management Manual, not one. You must treat the water quality volume from the first 1.2 inches of rainfall, provide 24-hour extended detention of the 1-year 24-hour storm for channel protection, hold the post-development 25-year 24-hour peak discharge to the…