PROJECT FUSION

ATLANTA, GEORGIA

Construction of a new two-tower building with a 60 ft. + deep excavation in downtown Atlanta requires complex dewatering solution to minimize risk to surrounding structures.

THE CHALLENGE

The project required a very deep excavation over 30 ft. below the groundwater table. The site was an entire city block and was bordered by a 100-year-old church and an underground Metropolitan Atlanta Rapid Transit Authority (MARTA) train station. A slow, controlled drawdown and limited movement of native material was necessary to minimize risk of settlement.

THE SOLUTION

Griffin designed and installed a 1,700 LF eductor system around the perimeter of the excavation. Groundwater modeling was used to project drawdown beneath adjacent structures and the model was updated with data from external groundwater monitoring points throughout the project. The eductor system was adjusted throughout the project to maintain water levels just below subgrade to minimize impact on the adjacent structures.

GRIFFIN DIFFERENCE

Griffin worked closely with the owner’s geotechnical consultant to monitor water levels during the drawdown period. This information was used to update the groundwater and settlement models and provided the information needed to adjust the system throughout the project to mitigate the risk of excessive settlement. The system maintained drawdown for over one year to allow for the substantial amount of underground work that was necessary.

READY FOR YOUR PROJECT?