• State Route 878 (also known as the Nassau Expressway) is an emergency evaluation route for more than 40,000 residents. The criticality of the roadway was proven during Hurricane Sandy in 2012.
• The Nassau Expressway is a main thoroughfare on Long Island, connecting residents and visitors with JFK Airport, Five Towns, Long Beach barrier island, and other major roadways.
• Prior to this project, the roadway would flood with every rain event and create large amounts of traffic. The existing state highway was 2.5 feet below the 100-year floodplain.
• $130 million design-build project for approximately 0.6 miles of roadway improvements that included raising the roadway three to four feet to reduce flooding, and the installation of a new multi-use pedestrian path, a state-of-the-art drainage system, synced traffic signals, and additional turning lanes.
• An existing peat and organic silt strata underlying the project site were susceptible to extensive primary and secondary consolidation settlement under the proposed embankment loading.
• UL-FGA was incorporated in the design through a NYSDOT Provisional Specification by the Tully Construction Company/AECOM design-build team in order to raise areas of Bay Boulevard and Incinerator Road, intersecting streets with the Expressway, to be above flood levels.
• UL-FGA as ground improvement, in combination with a shallow undercut, resulted in a net 0 surcharge on the soft, underlying soils in these areas.settlement under the proposed embankment loading.