unhurriedly past the viewing window in
Lower Granite Dam, Theresa Wilson glances
up from her knitting. “Chinook,” she says,
tapping her computer keyboard once to re-
cord its passage. The salmon pauses as if
to be admired. Its mottled scales flash
as it moves against the current of the
Snake River. Then it darts away, bound
upstream to the place where it was born.
Salmon and trout are anadromous: They
hatch in rivers, spend their lives at sea, then
return to their birthplaces to reproduce and
die. Here on the Snake in eastern Washing-
ton, that means traversing four hydroelectric
dams, an arduous undertaking few complete.
The Lower Granite is the last barrier
between this chinook and its spawning
grounds. It is one of 13 salmon and trout
species in the Pacific Northwest that the
federal government lists as threatened or
endangered. The concrete and steel struc-
ture in its way stands 151 feet tall and spans
a gorge, its turbines sending froth churn-
ing downstream. Clearing the wall requires
that a swimmer ascend a spiral structure
called a fish ladder to a resting pool, where
a viewing portal lets Wilson keep track of
them for University of Washington biol-
ogists and others monitoring the impact
dams have on piscine populations.
According to legend, the Snake brimmed
with so many fish when the explorers Lewis
and Clark arrived in 1805 that one could walk
from bank to bank on their backs. Today the
animals pass so rarely that Wilson spends
much of her eight-hour shift making socks.
As recently as the middle of the 20th cen-
tury, nearly 130,000 adult chinook returned to
these waters in a single year. Around 10,000
made the journey in 2017, a dip that threatens
the health of the river and all it sustains. More OPENING^SPREAD:^ GREG^VAUGHN/ALAMY;DANITA^DELIMONT/ALAMY