Abstract: A stormwater management system including: a plurality of adjacent modules with each module comprising alternating domed cell units and interconnector units and wherein each domed cell unit of a module includes a pair of spaced apart vertical sidewalls that curve outwards with respect to a centerline extending lengthwise through the module; and each interconnector unit of a module includes a pair of spaced apart vertical sidewalls 52 that curve inwards with respect to the same centerline, wherein the outwardly curved vertical sidewalls of the domed cell units of any module are thus nested with the inwardly curved vertical sidewalls of the interconnector units of the next adjacent module.