Moffat Tunnel - Construction

Construction

The Moffat Tunnel was cut under a shoulder of James Peak. A pioneer tunnel was bored parallel with the main tunnel to facilitate the work and was eight feet high and eight feet wide. In 1925 bad rock at the west end of the tunnel delayed construction and costs soared. The pioneer tunnel was officially 'holed' through on February 18, 1926, the blast of dynamite being set off by President Calvin Coolidge's pressing a key in Washington, and the program was broadcast by radio from the heart of the mountain. The pilot bore later became the water tunnel. Three more bond issues were sold before the tunnel was completed.

Although the original cost of the tunnel was pegged at $6.62 million, final assessments collected by the Moffat Tunnel district, including interest, were $23,972,843. The cost of the two tunnels was $15.6 million, which is $475 per linear foot ($1,558 per linear meter). The project excavated 750,000 cubic yards (570,000 m3), or 3,000,000,000 pounds (1,400,000 t) of rock, equal to 1,600 freight trains of 40 cars each. 28 people died during the five-year project, six in a single cave-in on July 30, 1926.

The tunnel is under lease to the City of Denver, which operates it as a trans-mountain line that transports water to the eastern slope of the range. The railroad tunnel was 'holed' through on July 7, 1927, and formally turned over to the lessee on February 26, 1928. Railroad connections through the tunnel shortened the distance between Denver and the Pacific coast by 176 miles (283 km). The tunnel took 48 months to bore—average daily progress being 21 feet (6.4 m). The first train passed through the tunnel in February 1928.