Fish gotta swim, but it’s not as easy as it used to be—even in Alaska, one of the planet’s last great strongholds for wild salmon. Compared to most other places, of course, Alaska’s salmon are doing relatively well, but they’re forced to navigate an increasing number of obstacles as more people move into the state and transportation infrastructure expands.
“It’s not so much a matter of existing dams in Alaska,” says Bill Rice, a former fish passage fish passage
Fish passage is the ability of fish or other aquatic species to move freely throughout their life to find food, reproduce, and complete their natural migration cycles. Millions of barriers to fish passage across the country are fragmenting habitat and leading to species declines. The U.S. Fish and Wildlife Service's National Fish Passage Program is working to reconnect watersheds to benefit both wildlife and people.
Learn more about fish passage engineer with U.S. Fish and Wildlife Service in Alaska who now addresses fish passage issues across the West and Great Plains. “Most of the state’s rivers are undammed. Poorly designed culverts where roads cross streams present the biggest problems.”
Particularly for juvenile salmon who can’t muscle their way upstream as well as adults returning to spawn. In Alaska, baby Chinook and Coho Salmon and resident fishes like Arctic Grayling and Rainbow Trout need to be able to find food and safe temperatures and flows throughout the seasons. Delays at roads can cost them their lives.
Staff in the U.S. Fish and Wildlife Service’s Habitat Branch take this issue seriously—and Heather Hanson and Jessica Straub are using their engineering skills to help clear the way for Alaska’s precious salmon runs.
Heather came to Alaska after earning an engineering degree from the University of Idaho and working for the U.S. Army Corps of Engineers on dam fish passage structures in the Pacific Northwest.
Jess grew up in New Hampshire, earned a Bachelor’s degree in Environmental Resource Engineering from the SUNY College of Environmental Engineering and Forestry at Syracuse, New York, and moved to Alaska after a stint in the Lower 48 working on water conservation projects.
Together, they design some of the most sophisticated and successful road-stream crossings on the planet—ones with both fish and floods in mind.
“Our habitat team has put in a lot of fish-friendly culverts,” says Heather, the U.S. Fish and Wildlife Service’s current fish passage engineer in Alaska. "And we have a lot more planned. The U.S. Fish and Wildlife Service is committed to doing everything possible to improve prospects for salmon.”
Jess has been working for Heather since August, 2019, and enjoys the fact that her job requires both intellectual rigor and vigorous physical effort.
“It’s a balance between the office and field work,” she says. “We design projects in the winter and mud season, and then construct and install the fish-friendly road-stream crossings during the summer. For me, the most challenging part is prolonged computer work. You’re at your desk for hours working with CAD programs on topo maps, stream cross-sections and project designs, it’s dark outside, and you kind of go into a black hole—you lose all sense of time.”
And the most rewarding part?
“Just the fact that you see a project come together from start to finish, and that it has an incredible payoff,” Jess says.
“On one project, we were able to install a culvert and restore stream flow at a tributary to Lake Orbin that contained a lot of juvenile Coho Salmon. We had a very hot summer and the juvenile salmon were suffocating, stressed out by a lack of oxygen and hot temperatures in the Lake. Once we established flow, you could literally see their relief—they just barreled up through the culvert and into the cool groundwater fed stream. That was tremendously satisfying.”
A new fish-friendly culvert in Kodiak helps baby salmon escape the heat.
Fish passage science and engineering have been around for a few decades, but the process has been greatly refined over the past few years. Thirty years ago, says Heather, the basic goal was to simply put in culverts that allowed a significant percentage of a stream’s flow to pass under roadways more or less unimpeded. The rest was left up to the fish, and results were mixed.
“These days, the agency’s general goal is on returning streams to as natural a condition as possible, and our passage designs reflect that,” says Heather. “And while our primary focus is on salmon, we’re also taking into account all the other fish and wildlife that inhabit any given project site. In addition to fish, mammals—moose, lynx, otters etc.—can also use them as safety corridors to avoid crossing roads.”
That means “not thinking in straight lines” and minimal emphasis on steel and concrete, Heather says. Rock banks are incorporated directly into culverts to provide the edges and niches young salmon need for resting, feeding and hiding from predators. Rock substrates can also be used to create low-flow channels in the bottom of the culverts to ensure the fish always have enough water for passage.
Also, bigger usually is best when it comes to culverts.
“We generally take out smaller culverts and replace them with large, embedded ones,” says Jess. “Smaller culverts disrupt the ability of a stream to transport sediment or build a floodplain. So our culverts can range from six to 35 feet in diameter. We want them to be at least as wide as the stream we’re working on.”
Alaska’s salmon are facing multiple obstacles involving everything from climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.
Learn more about climate change to heavy resource demands. These challenges may sometimes seem daunting, but the successes posted by fish passage engineers such as Heather and Jess demonstrate there’s also real reason for optimism.
“In terms of addressing and keeping habitat connected for fish, I personally think there’s a light at the end of the tunnel when it comes to resolving the most critical fish barriers over the next 10–20 years,” says Bill Rice. “And I think Heather and Jess are going to make big contributions toward that end.”
When did you start working for the U.S. Fish and Wildlife Service?
Heather: I started in 2015
Jess: August, 2019
What do you think people would find most surprising about your job?
Heather: They don’t think about culverts as a problem for fish passage. In reality, they’re small dams, and they can have a devastating effect on salmon and other fish — both juveniles and adults. Basically, our job is dam removal.
Jess: The number of different shoes I wear. It’s everything from waders to mukluks. Also, the diversity and the extreme beauty of our field sites.
How do Alaska’s wild places inspire you?
Heather: I love to get deep into our remote areas, far from roads and trails. That’s fairly easy because my husband is a pilot. We have a bush plane, and we fly out regularly to places with no human impact. We especially enjoy running skis on the plane during winter, flying up to glaciers, and skiing.
Jess: It’s just the majesty and beauty of the landscapes. It’s overwhelming, really, and it allows me to be my best possible self.
What’s your foremost concern about Alaska’s fish and wildlife?
Heather: Not proactively considering the needs of fish and wildlife in the initial design of development projects and infrastructure. There’s tremendous opportunity to balance all needs if we can work together up front. Infrastructure projects that accommodate the needs of fish, the natural, dynamic nature of rivers, and changing climatic conditions will perform better during floods and help sustain Alaska’s fisheries. We’ve seen a significant decline in fisheries since I’ve moved here and people talk about how many more fish there were 15 or 20 years ago. That’s very concerning to me.
Jess: The extremely warm temperatures we’re seeing and the droughts we’ve witnessed over the past several years. I’m deeply worried about the impacts, particularly on riparian riparian
Definition of riparian habitat or riparian areas.
Learn more about riparian environments.
When I’m not working, I’m…
Heather: …out playing in the backcountry.
Jess: I’m probably outside with my dog, Kai. He’s a big old mountaineering mutt.
What’s the greatest misconception people have about Alaska?
Heather: They think it’s a completely wild and undeveloped place. In reality, we have considerable development, even around remote villages. You’ll see roads for logging and mining — there’s just quite a bit of infrastructure out there. You especially see the impacts when you’re up in a small plane.
Jess: When I came up here, I thought things would be colder. I had just come from Syracuse, and often it’s a lot colder there. Temperatures are becoming milder up here, and that’s not necessarily a good thing.
What’s your most treasured memory of Alaska?
Heather: There are many of them, but one has to be working outside of Cordova on the Copper River Highway. It’s such a dramatic landscape, and bears are wandering around everywhere. It’s spectacular.
Jess: Seeing the northern lights for the first time. I was outside of Fairbanks in 2016, and they just drew my soul in.
What advice would you give someone interested in a career with the U.S. Fish and Wildlife Service?
Heather: Careers in the U.S. Fish and Wildlife Service are highly sought after, so I’d say you can’t give up. You have to demonstrate passion and commitment, and you have to persevere. If you keep at it, sooner or later you’ll get an opportunity.
Jess: Apply for every job that comes up. Every one. And sign up for the volunteer programs, and get to know people.
What wildlife species particularly moves you?
Heather: Definitely brown bears. They’re extremely important to Alaskan ecosystems, and they contribute an element of danger and excitement when you’re in the field, of course. My husband and I once flew out to some remote mudflats by a river and we camped on the beach, and the bears were fishing and roaring at each other all night. We didn’t get much sleep.
Jess: I’m moved by all of Alaska’s wildlife, but for me green sea turtles are my favorite wild species. My dad is a diving fanatic and I was certified for SCUBA at 12. We went to the Bay Islands near Honduras, and I got to see turtles up close. They just fascinated me — they still do.
In Alaska we are shared stewards of world renowned natural resources and our nation’s last true wild places. Our hope is that each generation has the opportunity to live with, live from, discover and enjoy the wildness of this awe-inspiring land and the people who love and depend on it.