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Brief description of the dive:

• On August 28, construction crews breached the last two dams on the California section of the Klamath River, allowing water to flow and restoring largest dam removal project in US history almost finished.
• The $450 million project involves demolishing four hydroelectric dams on the Klamath River in Oregon and California to restore habitat and provide passage for migrating fish. Omaha, Nebraska-based Kiewit is the prime contractor, while South Africa-based Knight Piésold is the lead civil design partner for the project.
• According to the Associated Press, the removal clears the way for salmon to swim freely through a major watershed near the California-Oregon border for the first time in more than a century and allows Chinook salmon to access key habitat just ahead of their fall spawning season. The demolition work is expected to be completed by late fall.

Diving Insight:

Dam removal has gained popularity in the United States over the past 50 years as the country has become increasingly recognizes its negative impact on the environment and a general state of disrepair.

The Infrastructure Investment and Jobs Act adds $585 million to the high-hazard dam grant program — more than 18 times more than the federal government awarded in 2019-2021, according to the Associated Press — including $75 million for dam removal. Last year, at least 18 Dam Removal Projects Used by IIJA In all, 80 items were removed, according to nonprofit environmental group American Rivers.

Many dams in the United States are old, unsafe, no longer fit for their original purpose, or require expensive repairs, and number of dams with high risk potential According to the American Society of Civil Engineers, that number has more than doubled in the past 20 years.

For example, dramatic Edenville and Sanford Dam Failures in 2020, which forced 10,000 people to evacuate and caused $175 million in damage to downstream homes, also underscored the dangers of aging there. In the aftermath, Edenville Michigan budgeted about $28 million for new money for removal and repair thereaccording to Bridge Michigan.

A broader trend

In this context, the removal of the Klamath dams illustrates a broader trend. Kiewit demolished the smallest of the four dams, Copco No. 2, in 2023 and JC Boyle Dam removed in July this year.

Currently, the contractor is completing demolition work on the last two dams in California: Iron Gate and Copco No. 1.

In 2021, Klamath River Renewal Corp. took over ownership of the dams from Pacific Power. According to the Associated Press, removing the dams won’t have a major impact on energy supplies: At full capacity, they produced less than 2% of the former utility’s energy.

While removing the Klamath River dams is a key step in the restoration process, the work is not over yet. Once the dams are completely removed and the reservoirs are drained, restoration contractor Resource Environmental Solutions and local tribes plant about 19 billion native seeds to restore the health of surrounding ecosystems, including culturally significant plants such as yampah and lomatium, important pollinator species such as milkweed, and tens of thousands of oak trees.

Klamath River Renewal Corp. will work with experts to monitor the impact of the dam removal on the river in the coming years. Area tribes, fisheries owners and environmental groups hope salmon will return to what was once the third-largest salmon river on the West Coast.