Figure Eight Loops
Route 2 / US 30
1914
Robert W. Hadlow, Columbia River Highway Historic District, National Historic Landmark Nomination
CS5. Structure: Figure-Eight Loops HAER No. OR-36
Location: HMP 24-26
Date: 1914
Designer: S. C. Lancaster
Owner: Oregon Department of Transportation
This CRH section is called the “Figure-Eight Loops” because it curves back on itself four times within 40 acres as it makes a 600-foot descent between Crown Point and Latourell Falls. Here, its designer, Lancaster, “developed distance” to maintain a grade of 5 percent or less and a minimum 100-foot turning radius. The Figure-Eight Loops were constructed with an elaborate system of concrete curbs, gutters, and drop inlet, along with tiled drains and culverts, to keep water from standing on the pavement and causing road deterioration and safety hazards.
Hadlow, Landmark Nomination, 17-18
Photo Currently Unavailable
[112] From Disc 1 of a series of CDs labelled "Glass Slide Collection", picked up at ODOT. Posted by Jonathan Ledbetter (http://blog.beaverstateroads.net) to Past and Present Views Along the Columbia River Highway Facebook Group on February 12, 2020
Photo Currently Unavailable
Evidence of a Missed TurnHistoric Columbia River Highway, Oregon. December 9, 2014Copyright © 2014 A. F. Litt, All Rights Reserved
Samuel C. Lancaster, The Columbia River Highway In Multnomah County
From Crown Point to Latourelle Falls, a distance of 2 1/2 miles, the road hangs on the steep slopes of the mountainside for the first mile and a half, where it is literally notched out of the solid rock, although the road has its full width of 24 feet, and at all danger points there have been erected substantial protection railings, similar to those along the shores of Lake Lucerne in Switzerland.
These protection walls are of rock, laid in cement mortar, a rustic appearance being obtained, the top of these walls being finished with a concrete coping ten inches deep and 20 inches wide, reinforced with four steel bars throughout their entire length.
Lancaster, 1914 60
Samuel C. Lancaster, The Columbia River Highway In Multnomah County
The elevation of Crown Point being 725 feet and the possible crossing of the stream below Latourelle Falls anywhere between 60 and 160 feet, there was not sufficient distance to get down directly on a 5 per cent grade. To overcome this it was necessary to "develop" distance, meaning that somewhere between these two points we must find ground that would permit of turning several times on curves of not less than 100 foot radius, and by looping back and forth on the side of the mountain come down on the maximum grade of 5 per cent.
There are four loops similar to the one on the now famous Tamalpais railroad, up Mt. Tamalpais in California, overlooking San Francisco and the bay. The road parallels itself five times but at different levels, yet all of the curves are easy, 100 feet being the least radius.
Lancaster, 1914 60
Links
Past and Present Views Along the Columbia River Highway: Cross and Dimmit Post Card, Figure 8 Loops, 1916 or 1917
"A view of the Figure Eights by Cross and Dimmitt from about 1916/1917. When I had reshot this image in 2019 the road was closed for the pandemic, and ODOT had gone through and removed debris in the gutter. Along with removing brush on the berms making it near identical to the original postcard view from a century ago." - Ben Carscallen, November 21, 2022
https://www.facebook.com/groups/483015922488601/posts/1314551772668341