Severson: (West Portal; RR East Portal is hidden from road; Satellite)
I was intrigued by why these tunnels were so short. And by the fact that the rock is so solid that the railroad didn't use any liner in the tunnel.
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| Tom Danneman posted |
A satellite quickly reveals why the road and rail tunnels are short. The tunnels go through outcroppings of basalt rock that the Columbia River has not eroded away. I recognize Drano Lake as the location of a BNSF bridge replacement project.
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| Satellite |
A street view confirms that the obstruction is not much taller than the tunnels. I included the background on the left because it better shows the tilt of the strata at this location.
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| Street View |
An overview of the location of the five tunnels.
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These are five of the seven tunnels that the Spokane, Portland & Seattle Railroad built in the early 1900s. Drano Lake Tunnel is the shortest at 122'. [ColumbiaRiverImages]
The following was provided by someone who wishes to remain anonymous.
Listed west to east:
Timetable mileposts and tunnel numbers are from BNSF NORTHWEST DIV—No. 8—March 14, 2018—Fallbridge Sub.
Tunnel simple descriptions and former names are from BN Portland Division Fallbridge Subdivision track profile/track chart published July 12, 1993 using data from May 1, 1993.
| Note | TT MP | # | Profile MP | Lining | Length(ft) | Name |
|---|---|---|---|---|---|---|
| (D) | MP 67.6 | 2 | 67.54 | ROCK LINED | 122' | DRANO TUNNEL |
| (B) | MP 67.9 | 3 | 67.94 | CONC LINED | 416' | BLUM TUNNEL |
| (S) | MP 68.4 | 4 | 68.40 | CONC LINED | 267' | SEVERSON TUNNEL |
| (O) | MP 69.1 | 5 | 69.04 | CONC LINED | 394' | OWL ROCK TUNNEL |
| (A) | MP 69.7 | 6 | 69.70 | CONC LINED | 657' | ALLIGATOR ROCK TUNNEL |
Tunnel simple descriptions and former names are from BN Portland Division Fallbridge Subdivision track profile/track chart published July 12, 1993 using data from May 1, 1993.
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