As the headings drew closer and officials predicted trains within a year, the final thousands of feet beneath James Peak brought remarkable engineering progress, treacherous ground, and a continuing human cost.
Moffat Tunnel Construction Happenings from 100 Years Ago
By September 1926, the Moffat Tunnel had entered one of the most consequential stretches of its construction. The great bore was visibly approaching completion, and public discussion increasingly shifted from whether the project could overcome its formidable engineering problems to how soon trains might actually pass beneath the Continental Divide. Yet the optimism surrounding that progress existed alongside a harsher reality underground. On Monday, September 13, Scott Long, an employee at West Portal, was injured in a cave-in so severely that one of his legs was later amputated. His ordeal came scarcely six weeks after the catastrophic July 30 cave-in at West Portal killed six men, underscoring that the final miles of construction were being won through ground repeatedly described as treacherous, soft, unstable, and exceptionally difficult to support.
The numbers nevertheless suggested that the two sides were drawing rapidly together. An engineering report dated September 15 placed the pioneer, or water, tunnel at 29,655 feet completed—92 percent of its total length—with only 2,728 feet separating the headings. The railroad tunnel headings had advanced 28,192 feet, or 87.4 percent, leaving 4,061 feet between them, while 22,912 feet of the full-size railroad bore had been completed. The same report noted that work remained delayed by treacherous ground on the west side. Other contemporary progress accounts varied somewhat with their reporting dates and measurements, but all pointed in the same direction: the pioneer bore was within roughly half a mile of breakthrough, and the principal railroad headings were separated by only a few thousand feet.
Those remaining feet, however, were not ordinary feet. When Moffat Tunnel Commission chairman W. P. Robinson remarked that the pioneer bore lacked only about 2,000 feet of completion, he reportedly added that “each of the 2,000 feet is a full twelve inches in length”—a wry acknowledgment that diminishing distance did not necessarily mean diminishing difficulty. Experienced miners and drillers remained in heavy demand. Earlier in the season, the commission had recruited hard rock drillers from the zinc mining districts around Joplin, Missouri, after a revival of mining throughout Colorado and the mountain West contributed to a shortage of skilled underground labor. By September 15, statewide employment reporting still listed demand for approximately 200 skilled and unskilled workers for the Moffat Tunnel project.
Construction was also spreading beyond the mountain itself. Extra crews were being placed on the tunnel approaches in an effort to finish as much work as possible before winter snow made outdoor construction impracticable. The West Portal approach extended approximately two miles, while the eastern approach was about one half mile long and included a bridge. The approaching winter therefore imposed its own deadline: while miners continued advancing beneath James Peak, surface crews were racing the season to prepare the railroad that would eventually carry trains into and out of the bore.
By late September, that convergence of progress encouraged increasingly confident predictions. Speaking before the Denver Lions Club on September 28, tunnel commission attorney Erskine Meyer said trains probably would be operating through the Moffat Tunnel within a year, despite approximately 2,700 feet of what was characterized as the softest and most dangerous ground yet encountered in railroad tunneling. Another contemporary account attributed to Meyer an even more ambitious expectation that trains would be running through the tunnel by July 1927. Such forecasts reflected genuine progress, but the language surrounding them is revealing: predictions of imminent completion were routinely accompanied by reminders of cave-ins, soft rock, water, unstable ground, and unprecedented engineering obstacles. The closer the project came to success, the more concentrated some of its most difficult work became.
That contradiction was not lost on contemporary observers. One Denver commentary complained that stories about the Moffat Tunnel had been repeated so frequently that many residents had ceased paying close attention, even as engineers elsewhere remained intensely interested in the project. The same commentary nevertheless expressed extraordinary confidence in the men overcoming those obstacles: “Into the minds of these men the word ‘failure’ never has penetrated, but always present there has been the word ‘success,’ and in a comparatively short time the fulfillment of the dream of Denver will be realized.”
The tunnel had already become a destination for technical study. During the mine surveying course offered earlier that summer at Idaho Springs, approximately twenty students traveled to inspect both portals under the supervision of Dr. Underhill. Mr. Hitchcock, of the firm carrying out the work, and resident engineers at both ends conducted the party through the tunnel. For mining students, the project offered an unusual opportunity to study ventilation, timbering, drainage, transportation, and large-scale underground construction while those problems were still actively being confronted.
The machinery itself demonstrated how thoroughly mechanized the undertaking had become. Conway belt loaders handled material in the smaller headings, while Osgood compressed air railroad shovels were used in the main headings. Battery locomotives provided transportation in the pioneer bore, and a trolley system served the main tunnel. A special drill carriage had also been developed for drilling the main headings. The eastern portion of the bore advanced largely through solid rock, where completed sections were coated with gunnite to protect against oxidation, water, and rock slabbing. The western half presented a starkly different problem. Much of it passed through extremely heavy ground requiring strong timber support, including creosoted Oregon timber at West Portal. The Lewis girder, developed by chief engineer George Lewis to support timbering in the main tunnel, was regarded by contemporaries as an important development in tunneling practice. The visiting students described the experience of traveling through thousands of feet supported by twelve inch and eighteen-inch timbers set side by side as “awe-inspiring,” and considered the tunnel an exceptional place to study methods for controlling bad ground.
British railway engineer J. Chapman Brown likewise traveled to Colorado specifically to inspect the tunnel and study the problems encountered there and the methods used to overcome them. Millard Milburn Rice brought the project to a still broader audience through his illustrated article, “Tunneling the Rockies,” in the Review of Reviews.
The tunnel was also becoming woven into Colorado’s broader public life. Southern California newspapers discussed the James Peak bore in terms of shortened transportation routes and prospective commerce. A Presbyterian minister drew “Spiritual Lessons” from its construction for a Sunday sermon. Two newly arrived tunnel employees who left a campfire burning along Jim Creek were hauled before a justice of the peace at West Portal and fined. And, as the 1926 election season gathered momentum, the tunnel reappeared in political rhetoric: supporters of former governor Oliver H. Shoup pointed to the creation of the tunnel commission and the financing framework established during his administration as evidence of his earlier record in office. By then, the Moffat Tunnel was more than an engineering project. It had become an economic promise, a political symbol, a subject of technical fascination, and a familiar feature of everyday Colorado conversation.
Yet Scott Long’s September 13 injury offers an essential corrective to the triumphal language surrounding those final months. Percentages such as 92 percent complete could make the remaining work appear almost inevitable; predictions of trains within a year could make completion seem little more than a matter of time. Underground, neither proposition was true. The last few thousand feet still had to be physically excavated through ground capable of collapsing without warning, and the consequences were borne by individual workers. Long survived his cave-in, but at the cost of a leg. His injury therefore belongs within the September progress story: while newspapers measured the shrinking distance between headings and officials predicted the arrival of trains, the mountain continued exacting a human price from the men closing that distance.
By the end of September 1926, the Moffat Tunnel stood tantalizingly close to the breakthrough toward which Colorado had worked for years. The pioneer headings were separated by only a fraction of the tunnel’s six mile length, the railroad headings followed close behind, approach construction was being rushed ahead of winter, hundreds of workers were still needed, and engineers were beginning to speak confidently of trains passing through James Peak within a year. But “nearly finished” did not mean nearly safe. Scott Long’s lost leg, the treacherous West Portal ground, and the repeated references to cave-ins throughout contemporary reporting make the deeper point unmistakable: some of the shortest distances remaining in the Moffat Tunnel were among the hardest—and most dangerous—to cross.
B. Travis Wright, MPS | Preserve Rollins Pass | September 11, 2026
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