Amateur In order to keep the higher portions of the Sierra
Amateur grade open in the winter, 37 miles (60 km) of timber snow
sheds were built between Blue Cañon and Truckee in addition to
utilizing snowplows pushed by locomotives, as well as manual shovelling.
With the advent of more efficient oil fired steam and later diesel electric
power to drive plows, flangers, spreaders, and rotary snow plows, most of
the wooden snowsheds have long since been removed as obsolete. Tunnels
1–5 and Tunnel 13 of the original 1860s tunnels on Track 1 of the Sierra
grade remain in use today, while additional new tunnels were later driven
when the grade was double tracked over the first quarter of the twentieth
century. In 1993, the Southern Pacific Railroad (which operated the CPRR-
built Oakland–Ogden line until its 1996 merger with the Union Pacific)
closed and pulled up the 6.7-mile (10.8 km) section of Track #1 over the
summit running between the Norden complex (Shed 26, MP 192.1)[74] and
the covered crossovers in Shed #47 (MP 198.8)[75] about a mile east of the
old flyover at Eder, bypassing and abandoning the tunnel 6–8 complex, the
concrete snowsheds just beyond them, and tunnels 9–12 ending at MP
195.7, all of which had been located on Track 1 within two miles of the
summit.[76] Since then all east- and westbound traffic has been run over the
Track #2 grade crossing the summit about one mile (1.6 km)
south of Donner Pass through the 10,322-foot-long (3,146 m) Tunnel #41
(“The Big Hole”) running under Mt. Judah between Soda Springs and Eder
which was opened in 1925 when the summit section of the grade was
double tracked. This routing change was made because
the Track 2 and Tunnel 41 Summit crossing is far easier and less expensive
to maintain and keep open in the harsh Sierra winters.[77]