Backfill material is placed and compacted on the sides of the Rainstore3 chamber. Then, cover material can be placed at Tulane University's
athletic practice fields.
Photo: Courtesy of Roger Tadlock, MKM Sales, 2014

Dealing with the high water table is problematic for Tulane University and all of New Orleans. Designers from Gould Evans Associates and Lee Ledbetter & Associates needed a way to store the site's runoff from stormwater while maximizing the limited area for an athletic practice field.

Invisible Structures Rainstore3 was chosen for the detention system in one chamber with two heights: one section at 5 units high (50cm) and the other area at 7 units high (70cm).

Precautions had to be made in the design of the system as the water table exerts upward force on the chambers at different times. Designer ended up wrapping nearly all of the sides of the chamber (leaving the top for infiltration) with an impermeable membrane. Calculations were made to see how buoyant this made the Rainstore3 system.

Then designers could counteract the upward buoyancy pressure with static pressure from the cover material and athletic field surface turf preventing the system from floating or popping up. Woodward Design Build was the general contractor. Durr Heavy Duty Construction subbed in for the Rainstore3 installation. The chamber is capable of holding 1,428 cubic meters of stormwater.