Partners Inter-Fluve and Columbia Land Trust visit an estuary restoration site three years post construction, with an eye on the future.
In late October, a crew of Columbia Land Trust stewards and staff from restoration design firm Inter-Fluve returned to the site of a tidal estuary restoration project at Kerry Island, located near Clatskanie, Oregon. Donning their requisite chest-high waders, the group observed changes in the site that have taken place in the three years since the partners excavated channels and breached levees to reconnect 100 acres of land that once functioned as part of the Columbia River’s floodplain.
Roughly a century ago, the installation of levees, tide gates, and ditches transformed Kerry Island from tidal wetlands into a cow pasture. This conversion of land is indicative of a broader pattern across the Columbia River Estuary. Today, more than 90 percent of the area that historically served as intertidal wetland has been converted for farmland, homes, or other uses. These areas provided vital nursery and shelter habitat for migrating salmon and steelhead from throughout the Columbia River Basin. Today, the challenge extends even more broadly, as a recent study determined that less than 15 percent of California, Oregon, and Washington’s estuaries remain intact. This matters not only for fish and wildlife that rely on estuaries for habitat but for human communities that benefit from the ecosystem’s ability to filter water and absorb storm surges.
While 100 acres on Kerry Island might not seem very significant given the scale of the challenges we face in restoring lost estuary habitat, the project serves as a valuable test kitchen for restoration planning. Like any good designers, the folks at Inter-Fluve and the Land Trust returned to their project to see how well conditions on the ground matched their anticipated outcomes. Did the channels they designed to re-introduce tidal waters into the landscape serve their intended purpose? Are natural processes widening the channels? Are fish utilizing the landscape for habitat? The team was curious to find out.
During the visit, the partners experienced a typical coastal mix of sun and driving rain, and quite literally immersed themselves in the site. Inter-Fluve Senior Watershed Hydrologist and Ecologist Caitlin Alcott waded into one of the channels and noted a head cut and plunge pool forming off of one of the channels.
Meanwhile, Land Trust Natural Area Manager Jeff Malone was excited to observe that a good length of new channel is forming as the natural flow of water continues the work started by the restoration design. Malone surmised that conditions more or less matched expectations.
While in the field, the crew observed killdeer along with an abundance of other shorebirds and waterfowl, as well as signs of use by beaver and white-tail deer. Earlier in the year, Malone noted an adult salmon in one of the channels in addition to juvenile salmon.
Together the partners left the visit with valuable information, including which pairs of waders have leaks that need to be addressed, an overarching affirmation that their designs and implementation plans for estuary restoration are working, and a few minor tweaks to improve future collaborations. A site restoration in progress—the slow but steady transformation of dry pasture to a bastion of estuarine biodiversity—is a beautiful thing. Perhaps more importantly, Kerry Island is proving ground for work that we need to scale quickly if we’re to conserve the salmon, wildlife, and natural processes that make the Northwest so unique.