Three miles of channels set the stage for a Sitka spruce swamp’s return.
Crews breached the 12-foot-high levee along the Grays River in late September in the middle of the night, when the tide was at its lowest point. By morning, 163-acre Kandoll Farm—once a flat expanse of grass—was full of water.
The breach was the culmination of a 10-weeklong restoration project—one of the most ambitious and complex that Columbia Land Trust has ever undertaken. It required the meticulous planning of a fluvial geomorphologist (a scientist who specializes in understanding the dynamics of rivers) and civil and water-resource engineers. Portland-based BCI Contracting, charged with digging three miles of new channels, even designed a one-of-a-kind amphibious excavator that could deal with the mud, water and challenging terrain. From the excavated earth, they formed several dozen 9- to 11-foothigh mounds—places where Sitka spruce will be planted and coaxed to grow again.
The result is a radically different landscape. The watery network will provide habitat for salmon, ducks and wetland species, but also address neighbors’ flood concerns.
To see the end goal, one has only to scan the periphery of Kandoll Farm, where remnants of 200-plus-year-old Sitka spruce still grow. The swamps are hauntingly beautiful. The understory is dark and dense, impenetrable without a machete. Limbs and layers of vegetation obscure deep pools and undulating channels. The terrain rises and falls, and everywhere are fallen trees: swamps display what biologists term “vertical complexity.”
Such swamps once dominated the Columbia River Estuary, but today only about 30 percent of the historic swamps remain. Cleared and drained for farms or timber, swamps once were considered unproductive. Today we understand better (though by no means completely) spruce swamps’ role in keeping the Columbia River Estuary healthy. They provide marvelous habitat for wildlife, but they also help control floods, capture sediment and improve water quality, among many other benefits.
“Recreating habitat is a long-term proposition,” says Stewardship Director Ian Sinks, noting that much work lies ahead. Acres of reed canary grass have to be removed. Thousands of native trees and shrubs must be planted. Changes in the channels and the habitat must be monitored and documented—a contribution to the evolving science of habitat restoration. —Jill Davis