As part of the Texas Facilities Commission (TFC) Capitol Complex master plan, TFC wanted to create a destination for visitors and employees. The redesigned Capitol Complex will have grand civic spaces connected by tree-lined promenades and served by new parking garages. Ensight Haynes Whaley (EHW) served as Master Engineer for the master planning project and Engineer of Record for several of the individual design and construction packages including the Texas Mall and Garage. The Texas Mall is a marquee feature of the new Capitol Complex; it features a grass lawn running the length of what once was Congress Avenue from The Texas Capital to the University of Texas campus that is framed by wide tree-lined walkways. At the south end of the lawn a natural rise in the elevation creates an ideal setting for a new amphitheater. Multiple elevated Portals guide pedestrians down cascading stairs bring daylight into a new 4,000 car, 5-level sub-terranean garage that spans the entire area under the lawn and extends below the two new office buildings at each end. Vehicular access points directly to existing streets will provide high-capacity ingress and egress to all levels of the garage. The garage also supports the utilities that serve the surrounding buildings.

EHW opted to utilize blindside waterproofing for the basement walls due to the limestone subsurface and to maximize the space on the site. This allowed the 50-foot-deep excavation to extend to the property lines while minimizing excavation and reducing the pressure on the basement walls. EHW used a flat-plate conventionally reinforced structural system for the garage. The top level of the garage has additional depth and reinforcing to support the added weight of the planted area of the mall above; soil depth in some areas reaches 6’ to accommodate large trees. EHW had to take into consideration the substantial slope of the site, 10 stories at the apex.