Patent ID: 8491224

Claim:
An apparatus for receiving and dispersing water, the apparatus comprising: a plastic arch-shaped corrugated chamber having a generally open bottom and including a plurality of corrugation crests and a plurality of corrugation valleys distributed along a length of the chamber, the corrugation crests and corrugation valleys extending transverse to a lengthwise axis of the chamber, wherein multiple corrugation valleys include a respective valley sub-corrugation feature thereon, where each corrugation valley is defined by a respective inner surface and a respective outer surface, and the valley sub-corrugation feature offsets both the inner surface and the outer surface in a common raised or recessed orientation in the region of the valley sub-corrugation; each valley sub-corrugation feature (i) is an external raised sub-corrugation located along at least a top portion of its respective corrugation valley, (ii) extends downward toward the bottom of the chamber on opposite sides of the chamber, (iii) has an upper portion with substantially uniform width and (iv) has lower portions on opposite sides of the chamber, each lower portion decreasing in width as it moves downward.