Which restoration took the longest to complete

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That has a psychological impact on our communities. The solution that Yurok and a coalition of other tribes and environmental organisations have long advocated for is the removal of the lower four of the eight dams on the Klamath. After painstaking negotiations, this led to the signing of an agreement between PacifiCorp which operates these dams and 40 other signatories, including tribes and state governments in The result will be stream-miles of restored habitat for salmon and other migratory species like steelhead trout and Pacific lamprey.

Opening up previously inaccessible spawning grounds will allow for greater genetic diversity and less crowding, says Belchik, which reduces the risk of disease transmission. By reconnecting springs and cold-water tributaries to the main Klamath River, Belchik says the water temperatures of the river as a whole would drop.

The return of cooler water, fed by snowmelt, will help make the fish more resilient in the face of climate change. And the return of naturally flowing sediment and a newly mobile riverbed would drastically reduce the habitat of the polychaete worms which release the salmon-killing C.

The removal of two smaller dams and fish passage improvements on the Penobscot River in Maine, which were completed in , have restored 2, miles of habitat for Atlantic salmon and other species , compensating for lost power by improving output from other dams.

The project led to a rebound in numbers returning to spawn : this year 1, salmon returned, compared to only in Other migratory fish have benefitted too: alewife and blueback herring returns have surged to 1. Just over 1, chinook salmon redds spawning nests were spotted upriver of where the second dam used to be in — encouraging signs that the chinook are recolonising this habitat.

In the same area, coho salmon smolts young fish have increased from 9, in to 17, in But it is perhaps the steelhead running in summer whose revival has been most dramatic.

On the Elwha River, numbers of salmon have recovered significantly since the removal of two large dams Credit: Getty Images. Like the phoenix, summer runs have arisen from the ashes. To remove dams as large as those on the Klamath River will be a complex operation. The year-old iconic bridge will have fulfilled all the necessary conditions for it to be included on the permanent list of UNESCO following the restoration process, according to Canalp. The marvel is the only stone bridge connecting Anatolia to the Balkans and extends over the Ergene River.

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