"Pardon my ignorance as a railfan but why do narrow gauge tracks exist?" I...

"Meandering" Like a fox....

Meander:  To wander a winding indirect course without aim...

"Animals blazed the original, meandering, indistinct trails across Cumbres Pass as they migrated back and forth between the San Luis and Chama Valleys.  Naturally the (indigenous people) followed the migrating animals when they went forth on hunting expeditions.  By the time of the American trappers and traders entered the region, the general route was fairly well known."
     Osterwald, "Ticket to Toltec", Western Guidways, Ltd 1976

"This was a strange route.  East of Cumbres Pass the track held to a stead 1.4 percent grade with a 20 degree curvature, apparently wandering aimlessly in spaghetti like contortions over the barren country...."
    LeMassena, "Rio Grande to the Pacific", Sundance Publications, Ltd. 1974 

It is a reach to understand why the question titling this post appeared on a discussion forum related to Narrow Gauge railroads, but there it was.  It has taken over two months to organize my thoughts for this series of posts.  The second was published first but only after I took to time to go back nearly 50  years to a 36 page paper I wrote for a Freshman English Class at Metropolitan State College in Denver.  The paper talked about a man named Moffat who built a railroad out of Denver.  That process brought again the understanding of how some people see organization in something while others see chaos.  The story of the building of that railroad over the Front Range of the Rockies is a direct analogue to climbing the steps on the San Juan Extension built twenty years earlier.  In an odd way the two remain some of the most powerful symbols of mountain railroading at its finest while so much else is gone.

There were certainly shorter or easier ways to get to the Silverton Basin than the jump over the Tusas Divide at Cumbres.  The two quotes above indicate, to this time there are those that imply the whole thing was rather like a clever job of following wildlife trails to get over a inconvenient obstacle.  Nothing could be further from the truth.    

The title for this post comes from a Facebook Inquiry on the "Narrow Gauge Discussion Group's" Page.  It is joy to see someone ask a fundamental question and my comment to him on Facebook inspired this post.  Over the course of the series there will a lot of aerial pictures which will enlarge if you click on them so keep your fingers ready to click a mouse or jab at a screen.  This post will use parts of the DNW&P (Standard Gauge - Denver Northwest and Pacific Railroad reorganized as the Denver and Salt Lake Railroad - Both named "The Moffat Route" in honor of the builder David H. Moffat - and on acquisition the D&RGW), in addition to The Denver and Rio Grande San Juan Extension National Historic Landmark (Narrow gauge - Cumbres and Toltec Scenic Railroad).

DNW&P - Leyden Mesa & the "Big 10's" to
Rollins (Corona) Pass

First and foremost this is a story about how to build a railroad on the cheap that was so well engineered and constructed that it now approaches its 140th birthday.  It is also a story about what worked and what didn't and why and finally it is about the challenge of building railroads in some of the most difficult geography on the face of the planet but, first things first:

In 2012, through the efforts of the "Friends", the U.S. Department of the Interior awarded the then operating Cumbres and Toltec Scenic Railroad the designation of National Historic Landmark.  This award to the now Denver and Rio Grande San Juan Extension National Historic Landmark was described in the award this way:

"In terms of length, scale of operations, completeness, extensiveness of its steam operations, and state of preservation, the Denver & Rio Grande Railroad San Juan Extension, Conejos and Archuleta Counties, CO and Rio Arriba County, NM is one of the country's best surviving examples of a narrow gauge system at the peak if American railroading, roughly 1870 to 1930."

And further,

"The 64-mile narrow gauge railroad is an operating steam railroad that has been in continuous service for nearly 130 years making it a key destination for historic rail riders.  Even within the context of comparable properties, the Cumbres & Toltec Scenic Railroad is an exceptional railroad cultural resource with an unparalleled combination of original fabric, original form and footprint, number of contributing features, intensity of operations, range of historic equipment and structures, continuity, and authenticity of operating practices and workplace culture." 

Unbeknownst to many among the accolades the Railroad has also been cited for excellence in Railroad Civil Engineering by the American Society of Civil Engineers ("ASCE").  In awarding the citation the ASCE included the entire 64 mile length of the railroad stating:

"The route from Antonito to Chama was one of the most difficult construction efforts of the entire D&RG era. Although there was urgency in pushing the line, labor and supplies seriously hampered these plans. Recognizing that work progress was well below D&RG productivity standards, the construction manager, R.F. Weitbrec, reported in the railroad’s 1880 Annual Report: “The most serious difficulty we have had to encounter has been and is still the securing of sufficient quantity of good labor. Since November, 1879, there has been an average of at least 1,000 laborers per month shipped from Denver and Pueblo to the various grading camps.” Most of these recruits deserted to the mines, returned home, or continued on to other parts due to the challenges of the rail construction project. Out of this problem of recruiting labor grew an important decision: the Rio Grande began recruiting local help, which meant “the brown, lean and ever-enduring Nuevo Mejicano. Indeed, as the Rio Grande headed toward Santa Fe and the San Juan, it was advancing into the heart of the New Mexico country and culture.” From that time forward, the “Nuevo Mejicano” would assume a dominant role in the building of, and later the maintenance of, the roadway and tracks of the narrow gauge. Even with the “Nuevo Mejicano”, however, labor shortages remained the chief obstacle to progress on the D&RG. To further rectify this situation, and in the process, introduce another source of change, an agent in Utah was appointed to recruit Mormon workers. In the fall of 1880, about 2,000 were contracted and became another prime source of labor for this difficult construction effort. Indeed, to this day, Mormon communities dot the San Luis Valley. 

The story of the people – the laborers and their families - who created and maintained this engineering marvel through some of the most challenging mountain terrain on the continent is yet to be fully told. The “Nuevo Mejicano” would embody the history of a region that had witnessed a territory that was, and had been, home to numerous Native Americans; the influences of Spanish conquest and settlement; the territory and Mexico winning its independence from Spain; the Mexican-American War and increasing white settlements; and a currency of trade and bartering in a self-sustained agrarian society that would give way to dependence on commercial goods and a money economy with the mining activity and the coming of the railroad."

The fundamentals are a series of geometric figures essential to the construction of a properly engineered railroad.  As the series goes forward remember these terms because I may be using a different parlance than you are used to. 

   Tangent, Transition, Curve  

Example of 4% Grade (4' rise in 100' - not to scale)

Calculating a 20◦ Curve - not to scale

By the way, in retrospect the question was probably a joke, based on the name of the person making the post, but the proper answer is actually more complex than "low cost", "lightweight equipment and roadbed", "fast construction" and ability to negotiate tight spaces....


This post ends with an aerial view of the "first step", which I have already discussed, and the next post is about the "second step"......

Thanks for reading

j