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Incline Railway In History

History of the Incline: Up and Down on the Incline Scene

by Charles E. Benjamin

Originally published in the September/October 1987 issue of Trolley Fare.
Used with permission of the author.

Skagit, the unchallenged giant of U.S. inclines, celebrates its 60th anniversary this year, with a magnificent setting deep in the northern Cascades and a fascinating history as part of one of the most unusual traction operations anywhere. First, its size. The Skagit, or Diablo Dam, incline carried loaded railroad freight cars up the side of Sourdough Mountain broadside, with its own rails 600 feet long climbing 338 feet vertically, ascending a 34.2-degree gradient (not too different from the length/gradient of the Monogahela Incline). The single platform car has four 4-wheel arch-bar trucks, riding on two parallel standard-gauge tracks. A third standard-gauge track runs up the middle for the counterweight car, with a dip in the middle to duck under the passing platform car.

The incline structure and haulage were built by the Washington Iron Works; the two cars were constructed by the Pacific Coast Engineering Co., both Seattle firms. Operation commenced late in the summer of 1927. The platform car weights 50 tons empty; the counterbalance car 43-3/8 tons. The latter is 23'10" long by 7'2" wide by 2' thick, with four 24"-diameter wheels; its bulk consists of steel scrap embedded in concrete. An extra 8 tons had to be added to this car when hauling up the huge transformers for the Ross Dam Powerhouse. A 400-hp motor drives the 1-3/8" diameter cables, with a capacity of 158,000 pounds.

The incline was an integral link in the electrified 9-mile section of the Skagit River Railway, which had been built by Seattle City Light to haul personnel and supplies to construction projects in the Skagit River Valley, about 140 miles northeast of Seattle. From the Great Northern railhead at Rockport, a 23-mile stream-powered division was completed by 1920 to the site of the Gorge powerhouse and dam at Newhalem.

The only route to the base of the next project, the Diablo Dam, was so steep (4-5%) and winding that steam power was impractical, so the electrified division was the result. Seven trolley freight locomotives and two electric box motors from defunct Seattle and Tacoma lines provided the motive power. Four classic wooden interurban cars from the Puget Sound Electric Railway and five more from the Oregon Electric were all demotorized and used as passenger trailers; the line had no electric-powered passenger cars (although they had two old J.G. Brill rail-buses for low-volume through service with the steam division).

At the top of the incline was quarter mile of additional electrified track, to the shore of the lake formed behind the new Diablo Dam. Benches were installed in one of the box motors for the convenience of tourists on this segment. The third dam, the Ross Dam, was built just above the head of this lake, and all of its construction supplies came on rail cars up the previously- described complex route, followed by a 4 1/2-mile tugboat-hauled car-ferry ride across the lake (two-car capacity), a winch- powered cable railway from a dock to Ross Yards, and finally a diesel-locomotive-hauled trip to the site. Small wonder that it took 12 years to build!

Excursions were popular from their beginning in 1928, but were temporarily discontinued at the start of World War II; after the Ross Dam was completed in 1949 they again became part of the line's dwindling traffic. In 1953 plans were drawn to replace the original Gorge Dam at Newhalem with a new higher dam which would flood most of the electric division's right-of-way. Rather than rebuild the line, Seattle City Light elected to use the almost-completed parallel highway (State Route 20), and the Skagit River Railway became a memory, with its last train on April 4, 1954.

Due to heightened security, Seattle City Light has restricted access to certain areas of the Skagit River Hydroelectric Project.

There is no public access to Ross and Diablo Powerhouses and the Incline Railway. Other seasonal attractions including the Gorge Powerhouse Visitors' Gallery and Ladder Creek Falls are open May through September. The Trail of the Cedars and the Gorge Dam Overlook Trail remain open year-round for public use.

For additional information, please visit
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