It’s that time of year again—the snowpack is melting across the watershed, sending pulses of water down our rivers. This annual event, known as the spring freshet, is one of the key forces shaping our messy rivers.
Flooding is a familiar experience for many in the Boundary, and for some, freshet season brings heightened anxiety. But while high water can be destructive in human terms, it’s also a vital ecological process. The spring freshet transports sediment—important for building floodplains and gravel beds—and moves coarse woody debris, which adds structure and complexity to aquatic habitats. These materials help rivers shift and meander, creating new side channels, wetlands, and microhabitats that support diverse plant and animal communities. In short, freshet is the river’s way of renewing itself.
Perhaps most critically, spring freshet sets the stage for the summer. As water spills out of riverbanks and slows in the floodplain, it spreads across wetlands and backchannels. Some of that water seeps into the ground, recharging the aquifers that supply us with cool, clean water during the dry months. The ground itself acts like a natural filter, cleaning the water as it moves through layers of soil and rock. This recharge is essential—not just for drinking water and irrigation but maintaining baseflows in rivers and streams high enough to support fish, amphibians, and other aquatic life through the hottest parts of the year.
When spring freshet is healthy, the whole system benefits: wetlands remain saturated, groundwater stays available, forests are less stressed, and salmonids and amphibians find refuge in cool, connected waters.
But we also know that climate change is making freshets less predictable. Warmer winters, rain-on-snow events, and altered snowpacks can all affect how—and when—water moves through the system. That’s why building resilience at the community level is so important.
Resilience can look like many things: protecting and restoring wetlands that act like sponges during high flows; reconnecting rivers to their floodplains; planting riparian vegetation that slows erosion and shades the water; and designing infrastructure that works with the river instead of against it. It also means making space for the river to be messy—to rise, fall, spread, and shift.
Freshet is not the enemy; it’s a pulse of life. And when we understand it, respect it, and make room for it, our communities and ecosystems are better off—not just in spring, but all year long.