Copco 2 Dam was removed first.
Photo courtesy Kiewit

“Dam removal is a growing industry,” says Dan Petersen, project manager for contractor Kiewit Infrastructure West Co. “A lot of that infrastructure is at its design life and past it, truly. I think the entire industry was watching the Klamath removal to see if it could be done … That’s probably the biggest thing that they have to overcome in doing their own dam removals is the questions [of whether] it actually makes a difference: Will the salmon come back?”

The salmon did come back, beginning just days after the dam removals, and their numbers have grown steadily since, with water quality also benefiting from sediment removal and reduced algal blooms. The goal was also to restore the river’s natural flow patterns, putting banks back into place, essentially making it look as though humans had never been there. “That’s kind of an uncommon process in the construction world,” says Petersen. Much of the materials used in that effort came from, or were returned to, their source. Of the 1 million cu yd of earth removed from Iron Gate Dam, 800,000 cu yd was returned to the original borrow pit. Riprap was created on site using local stone.

With dam removals complete, focus turns to restoring and revegetating 8,000 acres of former reservoir land
Photo courtesy Kiewit

Unique organizational and communication structures were integral to the project’s success. To start with, there was the Klamath River Renewal Corp., created specifically to oversee the dam removal after federal legislative action fizzled out, becoming the new license owner. Its establishment “had no precedent,” says CEO Mark Bransom. The organization’s dedicated purpose made it “easy to coordinate,” says Petersen. Working from a central office, under a progressive design-build contract, the corporation focused on permitting and agency coordination and Kiewit managed construction, but making sure “schedules were put together in sync with each other, and not really by surprise,” and roles under the decision-making structure were clearly delineated, adds Petersen.

Crews lived in camp housing for easier access to remote project sites
Photo courtesy Kiewit

Another significant meeting attendee was the contractor overseeing cultural resource monitoring crews, ensuring that work was integrated with construction activity. With the watershed home to many Indigenous groups, “our construction sites were just loaded with traditional fishing villages and home sites, homesteads, burial grounds, locations where there were artifacts. We were constantly implementing looting and vandalism plans, inadvertent discovery plans, cultural resources monitoring for purposes of protecting these known and unknown sensitive cultural resources,” says Bransom.

That communication consistency extended to the safety program, which led to zero recordable incidents despite the nature of the work, with “each dam a set of different scenarios,” says Petersen. There was rappelling and the use of winching systems to move people and heavy equipment down canyon walls for tunnel access. At Copco 1, crews performed a lake tap, tunneling 160 ft below water level, leaving 10 ft of a steel-reinforced 100-ft-thick concrete dam to be blasted out, akin to pulling a plug, when it was time to release the water. Two temporary 260-ft bridges were constructed at Iron Gate Dam to move heavy equipment across the river.

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Photo courtesy Kiewit

A safety manager traveled across the 40 worksites to ensure conformity with safety protocols. The team also made sure local communities stayed informed about work being performed, and created a crisis management plan covering everyone. Because of the project’s location, that included trainings around fire prevention and planning escape routes.

While Bransom says he’s not advocating for removals in general, the Klamath project serves as a strong template for those being planned. “We pioneered a number of new areas in project delivery, in risk management, and in the creation of this dam removal entity that others are learning from and then have already adopted,” says Bransom. In Europe, adds Petersen, there’s considerable interest in the Klamath Dam removals “and some of the dams that they’re looking to remove over there, so it’s greater and bigger than just this country … It’s affecting us globally in a positive way.”