Grand Central's Engineer: William J. Wilgus and the Planning of Modern Manhattan

CHAPTER SIX. Making Room for the Automobile: The Holland Tunnel

186 tunneling under rivers began in England in 1842, when Marc Isambard Brunel, after over nine years of effort, completed a tunnel under the Thames River in London. Brunel patented his “shield” method for constructing a tunnel under a riverbed through mud and silt. The shield consisted of a covered space for workers to excavate, a system to remove materials, and hydraulic jacks to push the shield forward . English engineers added compressed air and airlocks to keep water out and the use of cast-iron rings to line the wall of the tunnel as the shield moved forward.1 6 MAKING ROOM FOR THE AUTOMOBILE The Holland Tunnel The first use of the shield method in the United States was in 1869, when A. E. Beach, editor of Scientific American, supervised the construction of Manhattan’s first subway, which covered just a short distance under Broadway. The cars in this subway tunnel, which was a mere eight feet in diameter and lined with brick, were pushed forward by compressed air.2 In the 1870s, American engineers began to use the shield tunnel method for railroad tunnels under rivers through the silt and mud of the riverbed. Borrowing from the English methods, “subaqueous ” tunneling employed the shield technique with compressed air pumped in to keep the water out. Workers entered through an airlock and excavated material at the front of the shield. As the excavation continued, workers bolted new rings on to extend the tunnel walls. Hydraulic rams forced the shield forward as the tunnel advanced under the riverbed. Engineers developed variations to deal with different kinds of mud and silt encountered in riverbeds. One method, for especially porous silt, used a series of small doors in the shield at the forward end. The doors could be opened, allowing silt and mud to enter the completed section of the tunnel and be removed. With enough pressure, the hydraulic rams at the rear created the necessary force to push the shield forward. Bridge builders also used compressed air to keep water out as they dug foundations for bridges over rivers. In New York, the Roeblings employed caissons, airlocks , and compressed air to construct the foundations for the two towers of their world-famous Brooklyn Bridge, which opened on May 24, 1883. The two towers stood in the river, and the engineers needed to have the them rest on bedrock deep under the bottom of the East River. In this case, the caissons descended vertically through the mud and silt to reach bedrock. For a tunnel under a river, the shields moved horizontally under the riverbed through the same mud and silt. MAKING ROOM FOR THE AUTOMOBILE 187 The First Hudson River Passenger Tunnels In 1879, DeWitt C. “Colonel” Haskins, a Civil War veteran and railroad engineer who had gained experience working for the Union Pacific Railroad, announced plans to construct the first subaqueous shield tunnel in the port of New York. He planned to construct a railroad tunnel under the Hudson River linking Jersey City to lower Manhattan at Morton Street. During the “age of energy,” engineers Illustrations of the first tunnel under the Hudson River, providing rail passenger service between Manhattan and Hoboken, New Jersey, 1902. 188 GRAND CENTRAL’S ENGINEER like Haskins never hesitated to take on daunting challenges. After New York and New Jersey passed the necessary enabling legislation, Haskins formed the Hudson Tunnel Railroad Company, raised capital, and began construction. After many delays, legal battles with the railroads, and spending millions of dollars, Haskins stopped work on the tunnel in 1892. With over two thousand feet of tunnel completed, Haskins had clearly demonstrated the viability of subaqueous tunneling under the Hudson River. In 1902, the brilliant engineer and entrepreneur William McAdoo took over the Hudson River tunnel project. He reorganized the business as the Hudson & Manhattan Railroad and completed two tunnels in just six years. Rapid transit service between Jersey City and Cortland Street in Manhattan opened in 1908 and proved to be an immediate success. Decades later, the Port Authority took over the Hudson & Manhattan Railroad and continues to operate the tunnels as part of the PATH system. In effect, the Hudson & Manhattan had constructed a “subway” under the Hudson River, connecting Jersey City to Manhattan with the electric-powered cars, modeled after the equipment used on the IRT. Tens of thousands of daily commuters who lived in New Jersey but worked in...