The San Francisco International Airport intended to conduct a feasibility study of constructing a shoreline protection system that will protect the Airport property from the 1% annual chance flood or 100 year flood or base flood (base flood will be used hereon) defined by the Federal Emergency Management Administration (FEMA) and the sea level rise. The team was to provide recommendations for measures and future projects required to complete the shoreline protection system that will remove the Airport property from flood zone hazards; perform hydraulic and other analyses required to establish base flood elevation (BFE) for zone A at the Airport; and assess current conditions of approximately 30,000 feet of shoreline protection measures consisting of berms, concrete walls, vinyl sheet piles, and a combination of the above-mentioned protections in the last three (3) decades.
As Joint Venture partner for the first task, AGS reviewed the existing geotechnical information and observed the existing shoreline conditions to assess the damages caused by seepage to the existing shoreline dikes. The team also performed slope stability analyses to assess static and seismic stability of shoreline along the Airport perimeter.
The team then performed additional subsurface exploration including borings and CPTs to explore and evaluate subsurface conditions at the locations where adequate information did not exist. Based on the results of field exploration and laboratory testing, the team developed final geotechnical conclusions and recommendations regarding static and seismic stability and effectiveness of the existing dike and preferred shoreline improvement design along various parts of the SFO shoreline.