Bridge Replacements over a Single Weekend Require Months of Planning and Preparation 

School Street Grade Crossing Elimination 12-13-19

During the past year, the LIRR Expansion Project successfully eliminated two grade crossings with underpasses beneath grade crossings at Urban Avenue in North Hempstead and Covert Avenue in New Hyde Park. Work was completed with only a weekend suspension of railroad services and a 180-day closure of the street. Work at the next grade crossing elimination, School Street in Westbury, is underway.

The construction of these underpasses is an incredible feat of engineering in and of itself, but to ensure the work is successful, months of planning and preparation are required before the first shovel breaks ground. Once it’s determined it’s feasible to replace a grade crossing with a bridge, preliminary design work begins, including designing the new profile for the lowered roadway, potential solutions to relocate conflicting utilities and traffic studies to support potential detours.

The LIRR Expansion Project is committed to limiting the duration of street closures, so the team strives to complete as much work as possible prior to closing the road. This begins with utility relocations: overhead wires, poles and underground pipes must be removed and relocated outside of the work area. At School Street, the utilities include electric, cable, communications, water, sewer, gas and drainage, as well as LIRR communications and power. This work is typically completed under traffic control, with the street open to vehicles and pedestrians.

Once all utilities are removed from the work area, the installation of steel soldier piles begins. These piles serve as structural support for initial excavation and will remain in place, exposed to view, as support for the final precast concrete retaining wall. Only after the completion of the preliminary work will street closure take place and excavation begin.

The School Street grade crossing, located in the Village of Westbury and the Town of North Hempstead, is one of eight street-level crossings along the LIRR Main Line being eliminated as part of the LIRR Expansion Project from Floral Park to Hicksville. The School Street grade crossing is being reconstructed into a two-way grade separated underpass with a pedestrian sidewalk on the east side – Railroad Avenue will be reconstructed to maintain access to School Street. The elimination of the School Street grade crossing is part of the LIRR Expansion Project to strengthen the reliability of LIRR infrastructure and ultimately support the growth and development of Long Island. For more information and photos, please visit the School Street Grade Crossing Elimination project page on AModernLI.com.