Underground stormwater system is a win for retail development

March 2011, Vol. 66 No. 3

As it often happens in urban areas where land is at a premium, the 4.5-acre site did not have enough space to fit in both a detention pond and parking lot. The engineers took the only possible option — designing an underground stormwater system.

"If the engineers used an above-ground detention system, the site would have lost 22,000 sq. ft., which would have cost the owner about $166,000," said contractor Danny Clements at Danny Clements Builders. "Instead, an underground system is conveniently located under the parking lot, taking up no usable space."

The stormwater system for Looking Good was provided by CULTEC Inc. Clements preferred CULTEC's system because the system's unique internal manifold design eliminated the need for a costly external pipe header and allowed the company to offer a competitive price.

"We had to use a shallow system as the site was very flat, and the elevation of the parking lot was not much higher than the elevation of the drainage swale," said Paul McClendon, a project engineer with Larry Speaks and Associates. "Elevation of the swale is 218.5 feet, and elevation of the parking lot is only 224 feet, 5.5 feet above the swale, and this chamber was a good fit in these conditions."

About 460 units of CULTEC’s Recharger 150 were installed in a 14,580-square-foot bed of crushed limestone, providing 21,175 cubic feet of storage.