Snohomish County stream team bushwhacks a path to healthier waterways

BOTHELL — In a quiet cul-de-sac, a county stream team adorned with boots, waders and vests bushwhacked through brambles in a backyard north of Bothell.

Snohomish County is home to over 5,700 miles of rivers and streams, but “it’s rare that the creek itself is in the public domain,” said Frank Leonetti, a county project specialist.

“We have a lot of stream signs that are along the roads now, where the culverts go through and it’ll say, ‘This is a salmon-bearing stream,’ or even the stream name,” he said. “But often they’re not very visible.”

So every year, the team sends letters and knocks on doors to ask property owners if they can access the waters on private land, to pinpoint where county staff should focus restoration efforts.

The team, equipped with a net and measuring tools, surveyed a 100-meter stretch of Tambark Creek on Monday morning for the county’s State of Our Waters program. For the next three months, the crew will visit 40 sites like this one to track the health of local waterways. The county keeps a database of thousands of stream sites, and staff randomly select 30 to 50 to survey every year. This year, staff plan to check up on the Little Bear Creek, Swamp Creek and North Creek watersheds, among others.

In 2022, specialists visited a portion of Tambark Creek about 2 miles northeast of this week’s survey site. The team found the northern segment of the creek had good water quality, but poor habitat for aquatic life, according to the report.

Fish and other creatures in the creek have a limited menu of bugs to munch on — or “low insect diversity,” as the report says. This portion of the stream also lacks deep pools and woody material that make good hiding and spawning places for fish.

This week, specialists found the southern stretch of the creek had similar shortcomings. In the shallow stream, the crew worked in an assembly line, collecting samples at 11 spots as they traveled up the creek.

County habitat specialist Rob Plotnikoff worked ahead of the crew to capture tiny animals and insects known as benthic macroinvertebrates before other members disturbed the area. He knelt in the water and nestled a net into the creek bed. In front of the net, he rubbed rocks and sediment to loosen creatures from where they had settled.

The macroinvertebrates flowed into a container at the bottom of the net. Over the course of the summer, the team stores samples of the creatures until a taxonomist collects them for official identification in the fall.

Sifting through the debris Monday, Plotnikoff found a caddisfly larvae — one sign of a healthy stream, he said, because they are sensitive to water quality and flow.

Behind him, Leonetti and habitat specialist Stuart Baker used measuring rods to quantify how much habitat is available for wildlife. They measure the width, depth and slope of the stream.

Baker used a densiometer — essentially a compact mirror with grid lines — to note the stream’s shade, too. The mirror has 17 squares, so Baker counted how many were filled with tree coverage.

“What makes the biggest difference, often, is just how forested the stream buffers are around the creek,” Leonetti said. “That makes a huge difference as far as what we see in the stream, with wood that gets into the stream, from trees falling over, from branches falling down. The wood that’s in the creek is really important for forming habitat and providing cover for fish.”

At this section of Tambark Creek, a Western redcedar, bigleaf maple and red alder overlapped in a dense canopy, filling up all of the squares in the mirror, as Baker stood below.

Both Baker and Plotnikoff also measured a handful of rocks at random. Often small rocks and sediment are signs humans have disturbed the environment.

The crew repeats all of these steps at each stop.

Along the way, staff make other observations that numbers can’t describe: What does the shoreline look like? Are there invasive species?

Toward the end of the survey, staff found juvenile salmonids swimming in a deep pool under decayed wood.

The fish may have spawned there or migrated from North Creek. Still, their presence suggests aquatic life could thrive there if water remains cool and unpolluted.

The county doesn’t co-manage local salmon populations. But Leonetti said the stream team can help tribes and the state Department of Fish and Wildlife understand what conditions are like, at a microscopic level, for the fish.

County staff have surveyed local streams and rivers for decades. This year, the crew will return to coordinates staff surveyed before the State of Our Waters program started in 2017.

“That is definitely something that I think is important in the region: answering the question of whether things are getting better, or things are getting worse,” Leonetti said. “With all the restoration that we’ve been implementing region-wide with salmon recovery funding dollars, is that really making a difference?”

Snohomish County streamside landowners can do their part to protect their backyard waters, too, by avoiding pesticides and planting native flora along the banks, Leonetti said.

For more advice, you can reference the county’s Streamside Landowner Program. Or go to the county’s Stream Data Dashboard to see all of the places the team have surveyed.

Ta’Leah Van Sistine: 425-339-3460; taleah.vansistine@heraldnet.com; Twitter: @TaLeahRoseV.