coffer dam stretches across the Oma river in Ethipoia. The coffer dam is a smaller dam that blocks off the flow of the river during construction of the main dam, the Gibe III dam will eventually reach 778 feet high, spanning the picured canyon, and provide 1,870 megawatts of electricity to the surrounding region.
Courtesy Ernie and Candy Schrader
If there were an award for most-traveled Walla Wallan, Ernie Schrader would likely win it.
Schrader, who competes in endurance horse-racing in his spare time, has been to more than 35 countries while working on more than 100 different dams across the globe as an engineer.
“Every time I think I’m going to retire, I get a call from some dam that will use a new material, or be the highest in the world or something like that.”
– Ernie Schrader
Most recently, Schrader returned from an April visit to the Gibe III Dam on the Omo River in Ethiopia, for which he is a consulting engineer and principal designer. Schrader also spoke at the Africa 2013 conference in the Ethiopian capital, Addis Abbaba, a conference on hydropower and water storage.
The Gibe III will be the tallest dam on the African continent at roughly 778 feet high — and taller than any dam in the U.S. — and it will provide 1,870 megawatts of electricity to the region.
The dam is the tallest of its kind anywhere in the world, using a construction technique known as roller-compacted concrete (RCC), which Schrader helped pioneer in the 80s as the principal designer and construction manager for the Willow Creek Dam in Heppner.
“When you get up to this height, the water pressures are extraordinary,” Schrader said.
Although the dam will be the largest of its kind when finished, Schrader thinks the RCC method has yet to reach its limits.
“In the 1920s you had the Wright brothers, who thought you could only fly up to 30,000 feet,” Schrader said. “It’s just a matter of new technology and, when you’re pushing the limits, making sure you do it right.”
Gibe III is, not surprisingly, the third in a series of dams being built by the Ethiopian Electric Power Corporation. Gibe III’s power output will more than double the national output for Ethiopia.
In its entirety, the project is about 62 percent constructed as of Oct. 2012 and on schedule to finish in December of 2014, however Schrader, a principle advisor for the 1.55 billion Euro project ($2 billion), said the dam itself is only about 33 percent completed and has about two more years before it will be finished.
The mammoth construction project, which began in 2006, employs about 6,000 workers, the majority of which are Ethiopian.
One of the developments that makes the Gibe III dam possible is the method by which the concrete is delivered.
More than 35,000 tons of concrete are being poured per day. The concrete is made on site and transported down a sheer canyon wall to the construction site via a system of conveyor belts, where it is poured straight into position. As the concrete is poured, concrete rollers spread and compact the material. Once each layer dries, the next layer is poured on, allowing the dam to be constructed rapidly and economically.
Schrader, who holds a PhD. in mechanical engineering, is also employed on the Grand Ethiopian Rennaissance Dam Project (commonly referred to as the GERD), a controversial dam being built on the Blue Nile on Ethiopia’s Sudanese border.
The dam, which has been under contstruction for two years, will have a generating capacity of 5,250 megawatts, dwarfing any other power source on the continent.
But it has been the source of international tension, as Egypt fears the dam will impact its water rights from the Nile, for which the Blue Nile is one of two major tributaries, according to a June 17 Associated Press report.
The projected height of the dam is 558 feet and it will stretch more than a mile across the Blue Nile, creating the Millenium Resevoir, with a 63 billion cubic-meter capacity.
Schrader, 65, visits different projects frequently, sometimes having back-to-back trips to different countries for months at a time, but sometimes spending weeks at a time in Walla Walla.
He said the world-wide travel has become less enjoyable over the years, but he has no plans to retire.
“I would love to retire,” Schrader said. “But I think I never really will. Every time I think I’m going to retire, I get a call from some dam that will use a new material, or be the highest in the world or something like that.”
“How can you say no to that?”