6 years ago I was approached by Mike Pinker Americorp Watershed Steward Intern for the city of Gresham (near Portland) and working on a short film about beavers and why to coexist with them. He asked if I would share footage and of course I did. It was so long ago now it is kind of startling to see our beavers in this film, but Gresham has learned some things. I guess the arc of environmental justice really is long. But it bends towards beavers.
Gresham’s Beavers: Nuisance or Nature?
A decade ago, the city of Gresham faced off against mother nature with a conundrum on its hands — what do you do when beavers drastically change the water flows around a multi-million dollar facility?
The city, in partnership with other groups, had built the Columbia Slough Regional Water Quality Facility in 2008 to treat stormwater runoff from 965 acres of commercial and industrial land that was flowing untreated into the local waterways. But after it was completed between North Columbia Boulevard and the Columbia Slough, there were concerns about the facility not working as well as advertised.
And then the beavers came.
A family of the critters built an extensive series of dams along the terraces and berms leading up to the facility, changing the flows of the slough and further stressing those whom had heavily invested in the water quality building.
“There were a lot of heated conversations trying to figure out what do with the beavers,” said Katie Holzer, Gresham’s watershed scientist.
Well of course there are always concerns when beavers become neighbors. But there aren’t always smart ecologists on hand to talk about the good things they do. I wish every city had more of them. Just watch this film and imagine if they had worked for Martinez instead.
But then a series of decisions made this community more appealing to beavers. Partnerships between the city, local watershed councils and Metro Regional Government led to the reclaiming of large swaths of land along Johnson Creek. More trees and natural areas were protected, and busy development was kept away from the riparian corridors.
The push to buy the land as part of FEMA’s 100-year floodplain plan led to the happy coincidence of enticing beavers back. Now along Johnson Creek, 20 of the 21 known dams are located on public land.
“Beavers like a large area not affected by lights with wide open spaces to wander,” Wallace said. “The public lands provide an open space that does not provide any interruptions.”
And a changing of the mindset to figure out how to adjust to beavers, rather than trap and kill, led to an explosion within the population.
“We learned that we can work with and coexist with the beavers — it’s more successful than trying to remove them,” Holzer said.
Ya think? When Mike approached me I remember thinking he was in fairyland but he assured me that there were still lots of beaver naysayers. It’s never easy to learn something new. At least they had smart helpers.
Part of that is learning what makes beavers tick, and how to work around their idiosyncrasies. The city hired a beaver consultant, Jakob Shockey, at the start of the new year to come up with solutions. His main task was keeping beavers away from older culverts across the city, as beaver dams were causing flooding and blockage issues.The expert taught the city that hearing the trickling sound emitted by the culverts trigger a response in beavers to build a dam — a natural urge led by the desire to build their structures where two bodies of water meet.
“Now we are trying to get them away from hearing that sound,” Wallace said.
Oh I hate that people are stuck on that old trope. Do you really think deaf beavers don’t build dams? Of course they do. And so do beavers that live in such noisy urban environments that they can’t even hear that trickle. Beavers have lots of ways to be triggered to dam. The feeling of water pulling. The smell of water churning. Beavers might even be able to smell UNDERWATER, and who knows, it might smell different when you have a leak.
Plus there’s there’s that whole innate thing where beavers being rehabbed in someone’s dorm are known to dam the hall with magazines and tennis rackets. That’s not stimulated by the sound of running water,
“We embrace the beavers — our landscaping has always been to go with the flow, so they fit right in,” Zyvatkauskas said. “Each season is something totally different.”
The beavers build their dam in July when the creek gets lower and it becomes difficult for them to swim easily. Zyvatkauskas watches them in the evening and early dawn groom on the bank, drag logs to build the dam, and swim in the creek. At night, she can hear them gnaw on wood to keep their teeth sharp, or chortle amongst themselves.
“You get to see something extraordinary every day,” she said. “They have as much of a right to be here as we do.”
Now that’s more like it, Watching beavers is a great way to get on good terms with them. And for them to grow on you. Ahem.
Beavers are considered a keystone species, which have a large role in maintaining the structure of an ecological community. That has been a focus of Holzer’s studies. She has been amazed at the rate with which bringing beavers back to East Multnomah County has returned local waterways to a more naturalistic manner, undoing the artificial channels that were being created.
“I thought the timescale would be decades, but with beavers, it’s happening in 2-3 years,” she said.
Studies are showing the dams are lowering the temperature of streams, crucial for fish that rely on cool waters to spawn. Near Zyvatkauskas’ home, she has seen deer and coyote cross the dam like a bridge; ducks swim in the new pond; and even river otters using it as a waterslide to play.
“We are seeing native wildlife do well again now that the dams are back in our system,” Holzer said.
Gresham officials are continuing to refine its policies around wildlife. But the lessons taught by the beavers haven’t been lost. The mantra is manage, rather than removal, and Holzer and Wallace are continuing to study local species. Because who knows what the next savior of a multi-million dollar facility will be.
Let’s hope it sticks around. They say when you do something long enough it becomes a habit. Why not make Gresham’s habit of living with beavers something to teach other cities?
