Urban Rail/Bus Stations and Tunnels

The Puerto Suello Tunnel is a 400 m long single-track rail tunnel in San Rafael, California and was constructed in 1879. The 4.9 m wide and 6.8 m high tunnel was partially destroyed by a fire in 1961, was rebuilt for freight service in 1967 and closed in the mid-1980s. The tunnel was acquired by SMART in 2003, who retrofitted and then reopened it for commuter rail service in 2017.

The ground overburden above the tunnel reaches a maximum of 45 m and the tunnel was constructed using cut-and-cover and mined construction methodologies.

The East Side Access (ESA) project provides new Long Island Rail Road services to the east side of Manhattan, supplementing the existing service to Penn Station on Manhattan's west side and Atlantic Terminal in Brooklyn. ESA will serve approximately 162,000 customers a day, providing a faster and easier commute to the east side of Manhattan in a new 8-track terminal and concourse below Grand Central Terminal. The project encompasses more than 13 km of tunnelling.

The East Side Access (ESA) project provides new Long Island Rail Road service to the east side of Manhattan, supplementing existing service to Penn Station on Manhattan's west side and Atlantic Terminal in Brooklyn. ESA will serve approximately 162,000 customers a day, providing a faster and easier commute to the east side of Manhattan in a new 8-track terminal and concourse below Grand Central Terminal. The project encompasses more than 13 km of tunnelling.

Ottawa's Confederation Line runs from Tunney's Pasture station in the west to Blair station in the east, is 12.5 km long and includes 15 stations. The central piece is a 2.5 km long tunnel, running under the central business district of the city and including three underground stations. The twin track running tunnel and the three underground stations were constructed using the mined construction method in order to minimise surface disruption. The underground stations are located directly adjacent to existing, sensitive and historic buildings and required strict adherence to design and risk mitigation processing during construction. The Dr. G. Sauer & Partners on site team supported the contractor to meet these requirements.

The Relief Line South was a proposed expansion to the TTC Line 1 subway with five new stations planned from Osgoode to Pape Station undertaken by the TTC. The project has since been passed on to a new owner (Metrolinx) and further developed as the Ontario Line. Our role on the assignment included the 15% and 30% design for tunnel geometries, excavation and temporary support of two stations and one crossover. Tasks included production of 3D models, drawings, design reports and finite element analysis based on the SEM approach to tunnelling large caverns keeping surface disruption in urban areas to a minimum.

The TTP are delivering a new two track rail tunnel of approximately 176m length crossing the Highway 401. The purpose of the tracks is to increase capacity along the Kitchener GO commuter rail corridor as well as to accommodate the new Union-Pearson (UO) Express service. The new rail tunnels are mined under the 401/409 Highway using the Sequential Excavation Method (SEM). Our role on this assignment was to provide tunnel design services addressing the challenging conditions (e.g., very low overburden, intercepting piles and maximum settlement allowance) as well as providing on site design representation.