Uncertain national economic conditions in 1907 delayed the official start of construction until August 1, 1908. The project was divided into seven sections, one for each contracting company. Sections 3–6 were each; Sections 1–2 and 7 were of varying lengths. (Theoretically, to divide the line evenly, the seven sections should have been just over four miles each, but that would have placed the Pequest Fill entirely within Section 3 and the two viaducts within Section 7.) The amount of work per mile varied; the largest share apparently went to David W. Flickwir, whose Section 3 included Roseville Tunnel and the eastern half of the Pequest Fill. DL&W chief engineer George G. Ray oversaw the project, although given the size and remote location of the project, Assistant Chief Engineer F.L. Wheaton was assigned the task of overseeing the construction in person.
