The Hudson River Tunnel, New York
"This great enterprise, after several years of comparative inaction, has passed into the hands of new managers, having abundant capital, and under the new auspices the work of construction has been resumed in the most vigorous and active manner, with promise of early completion. The affairs are now controlled by London capitalists, and Sir John Fowler and Sir Benjamin Baker are the consulting engineers."
Scientific American November 1, 1890
Begun in November 1874 by American engineer Dewitt Clinton Haskin
(c1824-1900), the pioneering Hudson River railway tunnel
was a project beset with difficulties. The tunnel, or more correctly pair of tunnels, runs under the Hudson River between Fifteenth Street in Jersey City and Morton Street in Manhattan. These were early days in the development of reliable tunnelling technology — London's Tower Subway
was completed only four years earlier.
Haskin's experience came from the work he did in California on the Union Pacific Railway. He had made the preliminary surveys and soundings for the Hudson tunnel at his own expense as he thought the project so important. Despite delays, Haskin eventually completed the New Jersey and Manhattan shafts (1.65km apart), 701m of the tunnels on the Jersey side and 72m on the Manhattan side. However, work ground to a halt in 1882 on the death of one of the project's principle financial backers. Although it resumed, gradual loss of funding brought an end to Haskin's involvement by 1887.
Haskin had acted as his own chief engineer and had his own method of construction. He patented a method of using compressed air (at 50lbs/sq ft) to hold back the earthworks while the linings were installed. This method was successful but vulnerable if care was not taken to deal with air leaks promptly. Sadly, 20 workers were killed in a blowout in 1880, after which an additional 1.8m long iron pilot structure began to be used at the head of the tunnel. A second blowout had befallen the project in 1881.
The London contracting company S. Peason & Son took over the project in 1888. They appointed Baker and Fowler as consulting engineers, who in turn chose a team of their most trusted contractors. At the time, Baker and Fowler were still working on the City & South London Railway
(opened November 1890), the first true 'tube' railway line.
In 1889, work commenced once again under the Hudson River. Haskin's compressed air method was still used but the engineers decide to employ a tunnelling shield as well. They chose a form of Beach Hydraulic Shield. They also increased the thickness of the iron plate lining of the tunnel.
The shield, the associated hydraulic equipment and the erector, were designed by Ernest William Moir
under Baker's direction. All was manufactured by Sir William Arrol & Co in Glasgow. Both Moir and Arrol had worked with Baker on the Forth Rail Bridge
. Moir was also appointed engineer for the contractor, and William Hutton
was appointed chief engineer.
The Beach Hydraulic Shield was invented by A.E. Beach, erstwhile editor and proprieter of Scientific American, and was first used in 1868 in the construction of New York's Broadway underground railway tunnel. Like other shield designs, it allowed for permanent wall plate installation as it moved forward, digging. Under the Hudson, the river silt was fluid enough to be extruded through the shield doors.
Work progressed smoothly and rapidly until October 1891 when the Barings Brothers bank collapsed, making investors jittery. Project funds were withdrawn, the project virtually abandoned and Baker's involvement ceased. In 1902, work re-commenced under the auspices of the New York & New Jersey Railroad Company, who completed the tunnels in 1908. They are now part of the network known as the Downtown Hudson Tubes.
main references BDCE2
portrait of Baker
courtesy Institution of Civil Engineers