Tag Archives: Salmon restoration

Floodplains by Design solves problems through careful compromise

Water

The water understands
Civilization well;
It wets my foot, but prettily,
It chills my life, but wittily,
It is not disconcerted,
It is not broken-hearted:
Well used, it decketh joy,
Adorneth, doubleth joy:
Ill used, it will destroy,
In perfect time and measure
With a face of golden pleasure
Elegantly destroy.

— Ralph Waldo Emerson (1803-1882)

Floodplains by Design, a new program that combines salmon restoration with flood control, is a grand compromise between humans and nature.

I got to thinking about this notion while writing a story for the Encyclopedia of Puget Sound regarding the need to protect and restore floodplains in order to improve habitat for salmon and other species. The story is part of a series on Implementation Strategies to recover Puget Sound. Check out “Floodplain projects open doors to fewer floods and more salmon.”

Floodplains by Design is an idea born from the realization that building levees to reduce flooding generally causes rivers to rush faster and flow higher. Under these conditions, the rushing waters often break through or overtop the levees, forcing people to rebuild the structures taller and stronger than before.

Flooding along the Snoqualmie River
Photo: King County

Salmon, which have evolved through untold numbers of prehistoric floods, were somehow forgotten in the effort to protect homes and farmland built close to a river. Absent the levees, floodwaters would naturally spread out across the floodplain in a more relaxed flow that salmon can tolerate. High flows, on the other hand, can scour salmon eggs out of the gravel and flush young fish into treacherous places.

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