The roadway and parking areas were built with the base approximately 200 mm (8 in) below the natural surface to form a surface that was flush with the existing terrain. A geotextile was first placed over the muck soil as a separation and filtration layer. Next, 150 mm (6 in) depth Geoweb sections were placed over the geotextile fabric and secured with stakes. The sections were stapled together, and the cells infilled with #57 stone. Another 50 mm (2 in) of stone was placed on top of the Geoweb system for maximum water retention, drainage, and as a surface wear course.
Carlton memorial reserve roadway and parking, Sarasota County, Florida
Engineers Bishop and Associates required that the roadway and parking lot at T. Mabry Carlton, Jr. Memorial Reserve serve a dual function. The system was required to support loads over poor soils and also function as a stormwater retention system, storing the first one inch of rainfall. The retention system consisted of 150 mm (6 in) depth Geoweb sections and #57 stone infill. Seven inches of #57 stone with 40% voids yielded a capacity of 71 mm (2.8 in) of water storage, a 2.8 safety factor. The permeability rate of the underlying soil was 75 mm (3 in)/hour, which resulted in the system being available for the next storm within 2.3 hours, a safety factor of 31.3.