Trail notes are brought to you by the Riverfront Trail Board, a group of local volunteers who manage, help maintain and promote The Dalles Riverfront Trail.
To sponsor this regular feature please contact us: 541-386-1234 ext. 100 or email Info@Gorgenews.com.
Trail notes are brought to you by the Riverfront Trail Board, a group of local volunteers who manage, help maintain and promote The Dalles Riverfront Trail.
To sponsor this regular feature please contact us: 541-386-1234 ext. 100 or email Info@Gorgenews.com.
Our Riverfront Trail has overcome many obstacles in its 34 year history. From the initial vision of Dr. Boyd Jacobson, Dan Durow, Katy Young and many other citizen volunteers, the Trail was created through securing easements, generating funding, lobbying local business and government, finding creative sources of material such as recycled ground asphalt, and dogged determination and coordination to bring the Trail into being without using tax dollars.
The vision still remains to eventually complete the east end all the way to The Dalles Dam Visitor’s Center, but back when the intended west terminus at the Discovery Center was blocked by the railroad, a proposed pedestrian footbridge was rejected by Union Pacific because of the enormous cost of even one day of rail closure. It was determined that excavating a tunnel under the tracks would require an even longer closure and temporary cribbing would be very difficult to engineer with continuing train traffic.
The project languished until one fine day in the mid 1990’s, Dan Boldt, who had been involved in the project as a Riverfront Trail Board Member but was also serving as County Director of Public Works, took his daughter, Elise, on a bike riding west on the Trail. Expecting to catch up with his daughter where the trail abruptly terminated at the steep rocky slope of the raised railroad bed, Dan did not see his daughter there waiting. She had dragged her bike up the ragged footpath, past the sign prohibiting such a crossing, and was standing proudly up on the tracks waiting for Dan. Alarmed at her exposure, Dan scrambled up and over with his daughter and rode on to the Discovery Center, returning via a safer but still prohibited crossing east of the current trail. Dan found new motivation that day to find a solution to the railroad obstacle.
Via Pat Cimmiyotti, District Manager with ODOT in The Dalles, word came of a novel method for installing a large culvert through the kind of fill that supported the elevated rail bed — mostly compacted sand covered with basalt rock. Securing federal funding through the Transportation Enhancement program, a contractor was found and the railroad signed off on the project.
It was a massive coordination of effort. The tunnel was created by saturating the fill material with water, then drilling a network of holes around the intended path of the tunnel and inserting tubing to create a large refrigeration circuit to freeze an arch in the railroad bed material, making it structurally sound for continuing rail traffic. Massive hydraulic jacks were braced against basalt outcroppings near the North side of the rail bed and slowly they pushed the sharpened leading edge of solid 1-⅜” thick steel culvert into the frozen fill, just a few feet a day. A crew with a small excavator continually removed the material inside the advancing culvert to open the passage.
In 2001 when the crew finally pushed in the last section to complete the opening end to end, Dan and his second daughter, Alexa, were on hand to celebrate the engineering marvel that had solved the seven year puzzle. Alexa was privileged to be the first human to walk through the new passage that would make the Riverfront Trail’s connection to the Discovery Center finally complete.
The tunnel is a key feature of the Riverfront Trail that reflects a sustained and complicated effort by dedicated citizen volunteers.
Next time you go through the tunnel, stop and sing a few bars of your favorite song in the rich acoustic environment. I guarantee you’ll have never sounded so good. See you on the trail.
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