One culvert at a time
At the frontline of King County’s effort to protect and restore salmon habitat is the fish passage field team
The workday for the fish passage field team starts with a carpool ride from King Street Center to the Fauntleroy Ferry Terminal in West Seattle. Today the team has an important job: Locate, map, and assess stream crossings on Vashon Island.
As part of King County’s greater effort to protect and restore the habitat of native fish, the team will inventory and assess roughly 2,500 sites where streams pass under county owned roads and trails. They are looking for barriers that prevent salmon from reaching important habitat upstream.
Evan Lewis, project manager for the fish passage program, explains it best: “One of the best ways to help our salmon runs is to remove barriers that prevent them from reaching quality stream habitats. Just as we count on smooth roads crossing streams to get to where we want to go, salmon need to be able to get past county roads, trails, and other instream structures to reach habitat that’s essential for their growth and reproduction.”
Most of the stream crossings the team will assess are culverts, a type of pipe allowing a stream to flow freely beneath the road. Culverts come in all sizes and can be made of corrugated metal or concrete.
Barriers to fish passage caused by culverts can include water drops from the culvert to the stream that are too high for the fish to clear, a culvert that is too dry to swim through, or a culvert with a slope and a water flow that is too fast.
The field team is Rachel Crawford, Kat Krohn, Liora Llewellyn, and Zach Moore, with project oversight from Andrea Wong. The small size of the crew provides an opportunity to build close bonds. Liora reflects on the process of taking culvert measurements with Kat: “It’s almost as if we don’t have to talk to each other, we just know.”
Assessing the quality of a stream or culvert is physically demanding work that on occasion means cutting back large patches of blackberry while carefully sparing native plants struggling for equal space. This attention to detail requires crew members to be equipped with an in-depth knowledge of local plants and animals.
The unofficial member of the team is the trusty stadia rod, a surverying instrument that when paired with a laser receiver and range finder helps to measure the slope of a culvert. Measurements are entered into a database in real time using a smartphone or tablet which connects to the County’s mapping database. Other crucial equipment includes measuring tape, a flashlight to see into the murky depths of a culvert, and a solid pair of boots, which on occasion need to be dug out of the mud with a shovel.
Sometimes measurements don’t work out as planned because of spotty cell phone reception, or monster blackberry bushes that can’t be tamed in a single visit, and the team must trek back to a culvert site on another day or wait for a more opportune time to take measurements. Still, one-by-one, each culvert is assessed.
Aside from the satisfaction of helping to restore vital salmon habitat integral to the cultural and economic wellbeing of Washington State, work in the field for the fish passage team provides an excellent opportunity to experience nature in a way sometimes lost to adulthood. This nature doesn’t have to be a County owned park but can be the green space just off a busy road.
Trekking down into a ravine with Liora at the edge of the Vashon Island Golf and Country Club, we take special care to avoid spiderwebs and red-headed ants that colonize all surface space.
At the bottom of the ravine a tiny pool forms where the culvert once dumped out a stream. Here, insects called water striders dance across the water until Liora jumps in to take measurements with the stadia rod. At the bottom of the ravine the ground is cool and the air smells like dirt. Soon, hopefully salmon fry will populate this stream and have plenty of bugs to eat.
Later, on the ride back to Seattle Liora reflects on the uniqueness of her position: “One of the reasons I took this job is the ability to explore different places. Each culvert or stream has its own unique culture. Each culvert is its own problem, its own mystery you have to solve.”
At the end of the day the team ensures they haven’t unknowingly transferred any invasive hitchhikers, such as the New Zealand mud snail, a tenacious mollusk with a history of becoming an unwelcome pest in streams throughout the world. In invaded areas the snails rapidly become extremely abundant and deplete food sources for native water insects, an essential food source for baby salmon. Taking special care to eliminate transfer of the snails mud is scraped from equipment and boots are placed in a freezer with enough time to kill the unwanted critters. All in a day’s work for the Fish Passage Team.