As US dams age, removal is always an option—and it can be done well. //

Wending its way from the Olympic Mountains to the Strait of Juan de Fuca, Washington’s Elwha River is now free. For about century, the Elwha and Gilnes Canyon Dams corralled these waters. Both have since been removed, and the restoration of the watershed has started.

The dam-removal project was the largest to date in the US—though it won’t hold that position for long. The Klamath River dam removal project has begun, with four of its six dams—J.C. Boyle, Copco No. 1, Copco No. 2, and Iron Gate—set to be scuppered by the end of the year, and the drawdown started this week. (In fact, Copco No. 2 is already gone.)

Once the project is complete, the Klamath will run from Oregon to northwestern California largely unimpeded, allowing sediment, organic matter, and its restive waters to flow freely downriver while fish like salmon, trout, and other migratory species leap and wriggle their way upstream to spawn. //

The Dark Ars Praefectus
7y
10,623
org said:
That's too absolutist. Many small dams can only generate a few hundreds of kW or low double digit MW. That's a drop in the bucket for power generation but their local impact can be huge. I guess I mean you have to do case by case analysis to see when it's worth it.

Using the article as an example, the four dams being removed from the Klamath are John C Boyle (90 MW), Copco 1 (20 MW), Copco 2 (27 MW), and Iron Gate (18 MW). The four produced 686,000 MWh annually, or about 50.5% of their nameplate capacity. //

QuantifiableQuoll Ars Centurion
7y
272
greendave said:
Would have liked to see a discussion of the cost of these removals (reportedly $40-60 million for the two on The Elwha River, and $350 million overall for restoration). Those numbers seem exorbitant and make it hard to imagine that we'll be able to afford much removal/restoration in the long term.
The only reason PacificCorp, owner of the dams, agreed to the removal of the Klamath dams is because it was cost prohibitive to keep them in place. They needed mandatory upgrades and were already not competitive in a power generation market full of windmills/turbines/whatever and newer dams.

Source https://www.washingtonpost.com/climate-solutions/interactive/2023/klamath-river-dam-removal/