Tunnel No. 41
Tunnel Number 41, or the Big Hole, is a single-track railway tunnel underneath Mount Judah in the Sierra Nevada, near Norden, California.[1] It is owned by the Union Pacific Railroad,[2] in service as a part of the Roseville Subdivision of the Overland Route. Daily freight trains as well as Amtrak's California Zephyr utilize the line.
| Overview | |
|---|---|
| Other name(s) | The Big Hole, Summit Tunnel |
| Line | Roseville Subdivision |
| Location | Norden, California |
| Coordinates | 39°18′18″N 120°19′3″W / 39.30500°N 120.31750°W |
| Crosses | Donner Summit |
| Operation | |
| Opened | 1925 |
| Owner | Union Pacific Railroad |
| Traffic | freight, Amtrak |
| Technical | |
| Length | 10,325 ft (3,147 m) |
| No. of tracks | 1 |
| Track gauge | 4 ft 8+1⁄2 in (1,435 mm) standard gauge |
| Highest elevation | 6,887 ft (2,099 m) |
| Tunnel clearance | double-stack container capable |
History edit
The first bore through the Sierras, Tunnel Number 6, was built as part of the first transcontinental railroad. In 1901, Southern Pacific proposed building a long tunnel via a new alignment to both lower the track elevation and cut several miles off of the Donner Pass route.[3] Bores with lengths up to 18 miles (29 km) in length were reportedly considered, but an option for a 5-mile-long (8.0 km) tunnel route was under consideration as late as 1912. The uncertain corporate fate of the Central Pacific Railroad and the outbreak of World War I stalled further work.[4]
After Southern Pacific was cleared to take ownership of the Central Pacific in 1923, they announced a new tunneled route would be constructed and work began soon after.[4] The tunnel opened to traffic on September 19, 1925 as the third-longest rail tunnel in the United States at 10,325 feet (2 mi; 3,147 m) in length.[4][5][6] The new tunnel and cutoff shortened the route by 1.29 miles (2.08 km) and was 132 feet (40 m) lower in elevation than the previous bore through the summit, Tunnel No. 6.[7][6] The new and old single track routes were used in tandem as a double-tracked route until the old route was mothballed in 1993.[8] The line is capable of transporting double-stacked containers.[9]
See also edit
- List of tunnels documented by the Historic American Engineering Record in California
- Tunnel motors — locomotives designed to cope with long tunnels, especially those in the Sierra Nevada
References edit
- ^ Schwab, Jenell (March 21, 2012). "In search for missing skiers, officials find third man in Donner Summit train tunnel". Tahoe Daily Tribune. Retrieved November 10, 2020.
- ^ "UP's 2nd Largest Tunnel Gets Overhaul". Union Pacific. July 15, 2013. Retrieved November 10, 2022.
- ^ "Six Mile Tunnel Through the Sierras". The Sacramento Bee. Sacramento, California. August 17, 1901. p. 1. Retrieved February 14, 2024 – via Newspapers.com.
- ^ a b c Cobb, Daniel (July 11, 2023). "1900's Tunneling Through the Sierra". Sierra Sun. Retrieved February 14, 2024.
- ^ McDonald, Joseph; Nelson, Brian; Olson, Brian; Iden, Michael; Fritz, Steven; Honc, Randell (January 2008). "Locomotive Exhaust Temperatures During High Altitude Tunnel Operation in Donner Pass". ASME 2008 Internal Combustion Engine Division Spring Technical Conference. pp. 375–384. doi:10.1115/ICES2008-1625. ISBN 978-0-7918-4813-5. Retrieved November 10, 2020.
- ^ a b "Donner Pass: Southern Pacific's Sierra Crossing". Donner Summit Historical Society. Retrieved November 10, 2020.
- ^ Signor, John (1985). Donner Pass : Southern Pacific's Sierra crossing. San Marino, Calif: Golden West Books. ISBN 9780870950940.
- ^ Janet Fullwood (October 20, 2005). "In their tracks". Sacramento Bee. Retrieved November 10, 2020.
- ^ "UP improves Donner Pass tunnels to bolster double-stack operations". Progressive Railroading. November 24, 2009. Retrieved May 27, 2019.
External links edit
- Historic American Engineering Record (HAER) No. CA-215, "Central Pacific Transcontinental Railroad, Tunnel No. 41, Milepost 193.3, Donner, Placer County, CA", 8 photos, 4 data pages, 2 photo caption pages