The story of the Alberta Wheat Pool Elevator at Leduc.
Have any elevator enthusiasts out there ever noticed that the former Alberta Wheat Pool Elevator at Leduc looks a little different? It is a unique low-profile version of the Pool’s single composite 130,000 bushel elevator built on a standard plan during the 1960s and 1970s. It’s also unique as the only grain elevator that lies directly under the flight path to the main runway of an international airport and therein lies a story.
In 1976 the Alberta Wheat Pool revealed its intent to build a new elevator at the siding in Leduc. It wanted an elevator that would have a large enough capacity to replace all their aging elevators on the row, allowing for easier and more efficient grain handling. A single composite elevator built to the standard design stood normally over 27 meters hight (approximately 90 feet). This was considered a navigational hazard for airplanes approaching the airport—too high to get clearance from Transport Canada. So the Alberta Wheat Pool engineers went back to the drawing board to adjust the design, reducing its height. Transport Canada was satisfied with the new design, gave the green light and Leduc issued a building permit. Work began under AWP construction foreman Jim Pearson in spring 1978.
All elevators were basically built the same way. First a hole was excavated, cement foundation pads were poured and the steel pan set flush in the pit. The crew began construction of the sturdy cribbed walls, built to withstand the weight of the grain. The cribbing timbers were laid flat and spiked together. The cribbing of the exterior walls continued in rounds, in step with the cribbing of the inside bins, so that the elevator rose at an even height. As the cribbing progressed the crew installed the leg to elevate the grain, the distribution spout or gerber, the hopper and scales on the work floor, and the loading spout to the track below. The cupola on top was put together with pre-cut wood studs and shiplap or plywood walls. Finally the driveway was added, and the whole structure was clad with wood siding.
At Leduc, as Pearson later explained, changes had to be made to the standard plan. Instead of the standard 67 foot walls, the walls and bins were cribbed up only 59 feet, and the cribbing strength was reduced proportionately to the overall height of the building. The standard rounds of 2 by 6 cribbing were reduced by 5 feet and the higher 2 by 4 cribbing by 3 feet. To partially compensate for the lost volume, the design incorporated an annex 10 feet longer than was standard, giving the structure a footprint of 38 feet by 100 feet.
Lowering the walls 8 feet was still not enough to meet the required height restrictions. Another factor came into play. Elevators compress when they are filled with grain. The term telescope is used to describe a number of ways to allow the building to move in response to changing loads without causing damage to the structure. Normally, the leg is in one piece, so the cupola must be high enough to clear it as the elevator compresses. The Pool, wishing to install two metal legs—one for receiving grain and one for shipping, as was common by the 1970s—had to devise special legs at Leduc. They were telescoped in the middle and moved with the elevator to allow a lower profile than the standard one piece leg. A floating pulley in the pit took up the slack in the belt inside the leg. This one-of-a-kind system designed by Pool engineers allowed them to construct the cupola thirty inches below the regular height. When the new elevator was complete it was about the same height as the three 1920s elevators that it replaced.
The flight path-friendly elevator, with a capacity of 121, 000 bushels, was more expensive than a standard elevator. It cost $592,752 to build and opened in December 1978—the official ribbon cutting deferred until April 1979. It proudly served the farmers of Leduc until July 2000. When its days were clearly numbered and it, too, was faced with demolition the newly formed Alberta Legacy Development Society sprang into action to ensure its survival. Designated as a Provincial Historic Resource in 2003 and with fresh coat of paint in September 2007, it flaunts the once familiar and omnipresent Alberta Wheat Pool crest and logo.
So the next time you fly over Leduc into Edmonton, just before landing, look down to spot Alberta’s special stubby, one of the last Alberta Wheat Pool single-composite elevators standing and still the tallest building in downtown Leduc.
Written by: Judy Larmour.
2 thoughts on “Coming in Low”
The Jim Pearson mentioned in this article is Jim F. Pearson, who worked for the Alberta Wheat Pool. Myself, Jim A. Pearson is a vatorlogist who has written 4 books on the remaining grain elevators of Alberta, BC and Saskatchewan.
Thanks for the clarification, Jim.