Thomas & Hutton performed site design and utility coordination for a 72,000-square foot, 6-story Cay Building located over the City of Savannah’s owned and operated Whitaker Street underground parking garage located in downtown historic Savannah. Thomas & Hutton was originally involved in providing civil engineering services for the infrastructure redevelopment of Ellis Square adjacent to the Cay Building. The lease on a former parking garage expired, and the City seized the opportunity to convert the eyesore back to its original intended use as a public space. During this time, the owners of the Cay Building gave up subterranean rights to the City for an underground Whitaker Street Parking garage with the condition that the engineering structure could support a future building.
When the developer sought to construct the building, structural assessments and utility modifications were needed to ensure the subsurface garage infrastructure was adequate for the proposed office and ground-floor retail space. Thomas & Hutton’s surveyors located structural columns and reconfigured sewer and water lines to address the needed service reach for the proposed kitchens and restrooms throughout the building footprint while accommodating existing and proposed fire suppressing systems, drainage systems, and future elevator access shafts.
Thomas & Hutton was also responsible for as-built drawings for the placement of the building. The new structure rests on 32 columns extending into the subterranean garage, including a large cantilever section of slab supporting the building veneer over the garage foundation for sewer to run through. The columns replaced a secant wall that was temporarily installed and abandoned in place for the construction of the parking garage. Subsurface surveying activities required for the as-built drawings presented a unique challenge as all design and surveying had to account for adjacent systems that would add to the impact limitations above the parking garage including storm drainage, tree wells, and existing ADA accessibility.
Softening the massing of the building and providing a buffer to the adjacent Julian and Bryan Streets was the objective of Thomas & Hutton’s landscape architecture team. Custom raised planters were designed that were waterproofed and compatible with irrigation but did not place an additional burden on the garage. Working with limited space, custom tree vaults were inset into the ground in certain areas with customized grates over the tree well to limit sidewalk accessibility constraints while allowing the trees to thrive in the intense built environment.
The design team managed to maintain vehicular and pedestrian traffic circulation throughout the construction process. The garage remained operable and most of the parking deck was accessible throughout the construction process. Thomas & Hutton oversaw the traffic routing plan for the limited time that Julian Street was closed for construction.
The addition of the Cay Building to Ellis Square is significant as it completed the reclamation and redevelopment of the square. Ellis Square is one of Savannah’s four original squares, created in 1733. The City of Savannah began the task of restoring the square in 2004 by demolishing an existing above-ground parking deck, built in 1954, reintroducing a two-acre public space and adjacent subsurface parking garage. The Cay Building contributes to the enclosure of the square, by framing the public space with a vertical element. Its presence provides a room-like quality and helps define the space and feel comfortable for visitors. The design brings Ellis Square back to its former glory as an inviting public space and restores General Oglethorpe’s original layout for Savannah.