Popular Science - USA (2020 - Spring)

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habitat- restoration project ever. Biologists,
botanists, and volunteers planted tens of
thousands of indigenous trees, grasses,
and other plants on floodplains denuded by
the reservoirs. Salmon and trout ventured
upstream within months. Still, officials aug-
mented their meager numbers with animals
raised in hatcheries. Although the water re-
mained cloudy for more than two years, the
dirt and gravel eventually settled, creating
sandbars, beaches, and a vast estuary at
the river’s mouth near Port Angeles.
Researchers snorkeling the length of the
Elwha in 2018 counted 15,000 steelhead


and logjams— some created by the river,


pings among the alder trees, and a salmon
carcass hauled ashore by a predator.


this riparian zone. Restoring the habitat,
McHenry says, did more than save the fish.
It also created a natural defense against
flooding, opened the river to greater rec-
reational opportunities (federal and tribal
officials will consider allowing salmon fish-
ing in 2021), and resurrected woodlands
and shorefront. “Damming a river’s about
the most egregious thing you can do if you
want to mess it up,” he says. “You can argue
there are services you get out of that. But at
least in this part of the world, and, I guess, in
my value system, I think the services a wild
river offers way exceed damming it.”


shellfish, beavers, shorebirds, and other
creatures. None of the computer models the
federal government ran before the project
predicted this. “About 3.5 million cubic yards
of sediment were plopped here,” McHenry
says, “and now we have an estuary ecosystem
where there wasn’t one before.”
Not only can young fish make the transition
from fresh to salt water, the estuary at-
tracted enough Dungeness crab to support
a robust fishery. Just

shoreline. Today the free-running river has


ted with shrubs that provides habitat for


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