Tunnels: Sand Cut

In the late spring of 1871, construction along the Southern Pacific Railroad's Watsonville Branch was progressing at a feverish pace between Gilroy and Watsonville. The grade was relatively flat and there were few technical obstacles. A brief debate over whether the railroad would continue along the north or south side of the Pajaro River ended when the citizens of Watsonville failed to fund a $50,000 "subsidy" for the railroad. As a result, the Big Four chose a southerly route, which crossed the river at the western end of Pajaro Gap and continued west until reaching the tiny hamlet of Pajaro in Monterey County. This petty jab at Santa Cruz County proved to be an expensive misstep for the railroad barons, however, since it meant that the right-of-way now had to pass through the northernmost leg of the Gabilan Range.

Survey photograph showing storm damage at Sand Cut between Aromas and Vega stations on the Southern Pacific Railroad's Coast Division mainline, 1909. [Neil Vodden – colorized using MyHeritage]

The width of the hill was wider in 1871 than it is today. Over 150 years of farming in the adjacent fields have slowly eroded it away where it is now about 1,600 feet across in the area where the railroad passes. When grading crews first encountered the hill, it was probably over 4,000 feet across and presented an imposing roadblock to progress. Southern Pacific decided that the best course of action was to build a tunnel through the impediment. The Alta California reported that the “great tunnel…will, we believe, be when finished, the second largest in the State,” although it neglected to mention its actual anticipated length. Around 300 Chinese laborers were brought in to perform the task under the watchful eye of Superintendent Strowbridge. Construction began in September 1871. In the meantime, a bypass was built that likely followed the contour of the river further to the north until reconnecting with the mainline near San Juan Road west of the hill.

It seems that, while still under construction, the tunnel completely collapsed in mid-December. What was left was a deep, sandy sink that the San Francisco Examiner described as a sand cut. The name stuck, and from that point forward, regardless of the nature of the right-of-way between the former Mexican land grants of Rancho Las Aromitas y Agua Caliente and Rancho Vega del Río del Pájaro, the Coast Division mainline through the hill has been known as Sand Cut. Indeed, the name was so popular that the train station for the rural hamlet and workers’ village to the east of the tunnel became known officially as Sand Cut, a name that stuck until 1894 when it was renamed Aromas, after the rancho.

Map of Samuel Rea's subdivision of the Bardue Ranch, showing the Southern Pacific Railroad's right-of-way and the railroad west (geographic east) portal of the Sand Cut Tunnel, 1893. [Stanford University]

According to the records of J. W. Snyder, an early resident of Watsonville, it took two around two years for workers using pick, shovel, and dump cart, to clear the cut and reduce the grade sufficiently for a train to pass through it. Southern Pacific attempted to keep the cut open as a thoroughfare, but this proved a costly endeavor that set back the railroad many times what it would have saved had the track remained on the northern bank of the Pajaro River. Later accounts suggest that every vibration caused sand to fall back onto the railroad tracks, forcing crews to clear the right-of-way constantly. Within a few years, the railroad had enough and rebuilt the tunnel. Rather than bore a hole through the sand, though, the cut was cleaned and a shed was installed over the tracks. This was then backfilled with sand. This tunnel was open no later than December 1875.

For the years that it existed, the Sand Cut tunnel marked an important transition point on the Coast Division’s mainline. To the east of the tunnel was the curvy, narrow, and mountainous Pajaro Gap. To the west was the open plains of the Pajaro Valley blending seamlessly into the Monterey Bay and the Pacific Ocean beyond. Yet the tunnel was always troubled by cave-ins and sandy tracks. For example, in November 1900, a dry summer and fall led to a catastrophic collapse of the Sand Cut tunnel when a heavy rain saturated the foothills. It took several days for the cave-in to be repaired and service through the tunnel to be restored.

Aromas Station with boxcars being loaded with apricot pits. The Sand Cut is visible in the distance behind the depot, 1920s. [Monterey County Libraries – colorized using MyHeritage]

The tunnel was not a complete financial drain, though. Sand from around the tunnel was essential in the expansion of the freight yard at Pajaro in 1901. As the Coast Division neared its long-awaited connection with Los Angeles, Southern Pacific expected a huge uptick in freight passing through the Pajaro Valley and heading south. As a result, it upgraded and realigned much of the trackage at Pajaro, and all of this required tons of ballast and fill. According to the Pajaronian, more than 300 carloads of sand were hauled from Sand Cut and taken to the yard to fill holes and provide a bed for the crossties.

United States Geological Survey map of Aromas, with the Sand Cut at left, 1914.

Tunnel or cut, Sand Cut was destined to be a problem. When the San Francisco Earthquake struck on April 18, 1906, the tunnel was a mostly unremarked casualty. A simple report in the Santa Cruz Surf stated that “the sand cut between Watsonville and Gilroy is said to have been filled in by the temblor.” Considering the tunnel suffered cave-ins from even moderate storms, an earthquake with its main fault less than a mile away would certainly make in impression. In June 1906, Southern Pacific announced that the tunnel would be daylighted. Section Foreman Donahue with two work trains, a steam shovel, and about twenty men tore down the structure and leveled the cut. Sixty flatcars of sand were hauled out daily during the operation, and the final cut was about 60 feet wide when it was completed around mid-August. Southern Pacific hoped that the wider cut would “prevent any possible chance of a slide damaging the track.” However, turning the Sand Cut Tunnel into just Sand Cut was easier said than done.

In early March 1907, reports reached the Evening Sentinel that “all of the workmen within a long distance of Pajaro have been rushed to the [Aromas sand cut]. It was stated Monday evening that the sand was sliding into the cut almost as fast as it was taken out.” The slide was a result of a recent rainstorm. In an attempt to remedy it, Southern Pacific installed a retaining wall along the north side of the track. The problem never stopped, though, and every storm caused more sand to fall into the cut. On New Years’ Day 1910, the cut washed out again prompting “a big force of men” to drop what they were doing to help reopen the line. A second storm later in the month repeated the problem. The Evening News noted that “the sand is washing onto the tracks during rains, requiring constant work to keep it clear.” This is still the case even today.

View of the Sand Cut from the curve on Aromas Road, 2011. [Google Street View]

Over the past century, the gradient through the Sand Cut has been gradually lowered and the width of the cut increased until today it supports two parallel tracks. But sand remains a constant problem. The high, steep walls at the center of the cut are now supported by trees and anchor plants, yet sand still seeps through the roots, especially during winter storms. While no remnant of the old tunnel survives at Sand Cut, passage through the cut is still a claustrophobic journey along an otherwise pleasant stretch of railroad.

Geo-Coordinates & Access Rights:

East (Railroad West) portal: Approx. 36.8911N, 121.6512W
West (Railroad East) portal: Approx. 36.8928N, 121.6646W

The Sand Cut is located to the west of Aromas Community Park along the trackage of the Union Pacific Railroad. This stretch of right-of-way remains in daily use. No trespassing is allowed and doing so can be highly dangerous.

Citations & Credits:

• Alta California
• Evening News
• Evening Pajaronian
• Evening Sentinel
• Salinas Morning Post
• San Francisco Examiner
• San Jose Herald
• San Jose Weekly Mercury
• Santa Cruz Sentinel
• Santa Cruz Surf
• Southern Pacific Railroad, various timetables.