USFWS Going All in on Fish Passage

It’s said that before the Madison River was divided into upper and lower sections by a dam, it was a prolific Arctic grayling fishery. West of there, steelhead and salmon were abundant in the Snake and Columbia River drainages of the Northwest. Throughout the Eastern U.S., brook trout thrived. The same is true for catfish in China, eels in Germany, chubs in Colorado, and dolphins in Pakistan. But since dams have become ubiquitous worldwide, fish habitat and biodiversity have fallen, worldwide.  

Dams affect fish habitat, river flow rates, water temperatures, sediments, oxygen levels, timing of spikes and low water levels, and of course, fish passage.

“Fish passage,” which goes by other names like “fish migration,” “connectivity,” and in cases of restoration, “fish-barrier removal,” has been a hot topic among conservation-minded anglers over the past decade or two. Many believe it is a key piece to the continued survival of many of our most imperiled fish species.

These terms refer to eliminating obstacles that prevent a fish population from migrating to a given area—often an area that is an important coldwater refuge or spawning habitat. According to the U.S. Fish and Wildlife Service (USFWS), fish passage is: “the ability of fish or other aquatic species to move throughout an aquatic system among all habitats necessary to complete their life cycle.” And of course, more fishing is better for fishermen.

It’s often dams that block the rivers, but other times it’s culverts that are perched too high or are too small for fish migration or that get blocked with debris after a storm, or aquifer draining from past mining activities, warm weather, or irrigation draw that dewaters a stream to the point that fish can no longer navigate a given stretch. Therefore, the projects are focused on dam removal, fish ladders that all fish can use to bypass dams, and fish-friendly culverts.

To this end, the recent federal Bipartisan Infrastructure Law (BIL), signed into law in late 2021, designated millions of dollars to help restore connectivity to fisheries and add climate resilience, via the National Fish Passage Program. In 2023 alone, USFWS granted about $35 million to fund 39 projects in 22 states.

Projects like the “Upper Bear River Fish Passage for Native Bear River Cutthroat” and the “Potomac Headwaters Fish Passage Restoration” (which aims to give more habitat in the upper end of the drainage to Eastern brook trout) are of particular interest to fly fishers.

“Waterways have been reconnected, fish migration is improved, and local economies have been stimulated through the president’s Bipartisan Infrastructure Law,” USFWS Director Martha Williams said. “With $36 million in additional investments in fish passage projects, communities will benefit from dam removals, culvert replacements, and reduced flooding. The Service will continue to work with tribes, state and local agencies, non-governmental organizations, and conservation partners to reconnect important aquatic systems.”

Bear River Cutthroats

The Upper Bear River Project, located in a remote high-desert area in Utah and Wyoming, aims to remove four fish barriers, giving native Bear River cutts (considered the same species as Bonneville cutthroat trout for this project) 45 additional miles of coldwater habitat that will provide a cold-water refuge in summer along with productive spawning grounds.

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“We’re allowing them to get higher up the watershed,” Kevin Johnson, regional fish passage coordinator for the

Mountain-Prairie Region, said. “We’re seeing across the country that some of the lower reaches of these watersheds the temperatures are increasing. So we’re providing more cold-water habitat for these coldwater species, giving them more range within which to exist over different temperature ranges.”

These projects also exemplify how private landowners, irrigators, recreationists,

and government agencies can work together to improve conditions for everyone. Anglers get more fish and fish habitat, sometimes get new access, agencies fulfill their missions to increase native fish populations, and landowners and irrigators often get improved infrastructure without any changes to their water rights.

“It’s a win-win,” Johnson said. “We’re not stopping the irrigation diversions from collecting the needed water—we’re just redesigning them and reconstructing for fish passage and irrigation. And it creates good neighbors.”

Like other cutthroat subspecies, Bonneville cutthroats (Oncorhynchus clarkii utah) in the Bear River have faced various threats and challenges that have contributed to the decline of their populations, including habitat destruction, competition with nonnative species, overfishing, and water quality issues. This species’s greatest stronghold at one time was Lake Bonneville, which over time dried up and became Utah’s Great Salt Lake, which does not support fish due to its salinity.

Though there isn’t specific “before” data on the Bear River cutthroat population, Johnson expects the numbers to rise once the connectivity is complete.

“As a biologist, and someone who does this and has seen the benefits of these projects, I can’t imagine (the population) wouldn’t (rise),” he said.

To learn how best to retrofit under-road culverts, the USFWS Fish Technology Center in Bozeman, Montana recently installed an impressive 56-foot-long fish flume to research different species’ capability of migrating against water currents under controlled factors like barrier height, flow rate, and water temperature. The employees have tested things like how well rainbow and Yellowstone cutthroat trout can move under varying conditions, how tall of a barrier northern pike can leap over, and the abilities of sturgeon, sauger, and dace among others. And the length of the flume is not random—it’s the exact width of a standard two-lane road including shoulders, according to Kevin Kappenman, a research fish biologist at the Fish Technology Center. They also test so-called “Denil” fish ladders and other innovative methods of potential fish passage. Denil ladders are narrow flumes with “baffle” boards that have downward-arrow-shaped cutouts that create soft water at the bottom, which allows fish to swim up the ladder on the bottom. Though the surface water is moving fast, the bottom water is very slow, or even a back eddy.

“Some fish are very strong swimmers, others are less so,” Johnson added.

Potomac Headwaters

Similar to the Bear River project, the Potomac Headwaters Fish Passage Restoration Project seeks to connect nearly 200 miles of river habitat high in that drainage for brook trout, American eels, and other species. This project mostly involves culvert replacements utilizing the findings of the Fish Technology Center in Montana, and is being done in conjunction with efforts from Trout Unlimited, private landowners, the West Virginia Department of Transportation, and more. Up to 17 fish barriers (mostly roads with culverts) are slated for removal or improvement across Maryland, Virginia, and West Virginia. USFWS is hoping to have this project completed in 2025.

Like cutthroat trout in the West, native Eastern brook trout (Salvelinus fontinalis) were once the dominant trout species in the Eastern U.S. Some of the key factors in their decline include habitat fragmentation, pollution, competition from nonnative species, invasives like the hemlock woolly adelgid destroying tree cover and raising water temperatures, and overfishing.

“This project is going to have big benefits in terms of opening up refugia—those cold, clean water areas where the brook trout can get to in the summer months, and improving access to spawning and rearing habitat,” said Cathy Bozek, the USFWS National Fish Passage Program’s Northeast regional coordinator.

Beyond the brook trout and American eels, Bozek feels this project could also potentially benefit the Chesapeake Bay’s struggling striped bass population.

“These projects have huge ripple effects past the individual site,” she said. “It’s really beneficial for all species in the river, from small resident fish to mussel species, and that can have a big effect downstream when we’re looking at the prey base for other species. It’s also improving water quality, which is a huge concern with Chesapeake Bay.”

(In related news, the USFWS also recently announced nearly $20 million in total for its Chesapeake WILD Program, which aims to “improve recreational access along more than 31 miles of river and trails, restore more than 32 riparian miles of forest habitat, improve passage along nearly 120 river miles for migratory fish species, and protect more than 4,700 acres of fish and wildlife habitat, including 2,000 acres of key wildlife corridors in high-elevation areas that will allow species to shift habitats in response to climate change.”)

Nationwide Effort

Projects like those two are going on all over the country to benefit native fish and communities. Extensive work is being done on Montana’s Clark Fork to benefit the imperiled bull trout and westslope cutthroat trout, for example. Culverts are being improved on the West Fork of the Black River in Arizona to aid Apache trout. Tributaries to Montana’s Blackfoot River are being worked on for bull trout and Arctic grayling. The southern Appalachians are seeing sedimentation and connectivity improvements in North Carolina’s Alarka Creek. Diversion dams on Wyoming’s upper Green River are being retrofitted. All along the West Coast, salmon barriers are coming down or being revamped. According to the website, the program has worked with over 2,000 local communities, states, tribes and private landowners to remove or bypass 3,500 barriers to fish passage and reopen access to over 64,000 miles of habitat and over 193,000 acres of wetland, since 1999.

Funding for these projects comes via competitive grants that are judged by a panel upon certain criteria such as whether or not there is a partner group or groups with their own funds to contribute, ecological value, whether or not it supports native fish, recreational issues, flood control, and more. The window to submit a letter of interest for a grant from this program closed in November of 2023.  

These projects are often done with a partner group, which often provides matching funds (or more), such as Trout Unlimited, the Nature Conservancy, state agencies, municipalities, and local water conservation districts. From 2006 to 2021, the USFWS Mountain-Prairie Region alone has pledged about $12 million to fish passage projects, which has garnered over $50 million in matching funds from partners, according to Johnson.

“That’s a huge benefit,” he said. “It’s a great way to leverage these dollars.”

Another element to these projects is climate resiliency. Recent flooding in Vermont and Massachusetts highlighted this—100 percent of the recently reconstructed fish-friendly culverts survived while many older culverts did not. And as climate change continues to bring more extreme weather events like storms and flooding, there’s more than fish passage at stake.

“We’re seeing these increased precipitation events in the Northeast with climate change and know that there will be increased flows in the rivers and this can lead to flooding and catastrophic failure of some of the infrastructure,” Bozek said. “It’s not good for people, and it’s not good for the river systems either. So these are providing really big climate resiliency benefits, making sure that even in those drought times that we have flow in our rivers.

“‘Right-sizing’ the culverts is a really big benefit for the fish,” she added. “And for the people as we see really resilient infrastructure. It’s providing exceptional benefits for our fish species that are our trust resources for the Fish and Wildlife Service, it’s providing big habitat benefits, and big benefits for climate resiliency.”

Bozek noted that this can be especially important in some Mid-Atlantic areas that struggle with poverty as well.  

“Many in the area of this project are underserved and disadvantaged communities, thinking about some of these rural areas in Maryland and Virginia and West Virginia,” she said.

The results of this program will hopefully be felt for generations to come, as we all learn how to cope with the effects of a warming world.  

“These are really important to helping fish populations,” Johnson added. “Especially as flows are changing. We’re seeing flashier streams—either really low or really high flows and they come and go. The more we can create connectivity throughout a watershed, that is always going to be beneficial to the aquatic species and the aquatic ecosystem. And it creates opportunities for anglers because we’re opening up streams that have had barriers since way back when. By opening up those barriers, we’re allowing to repopulate these habitats in their watersheds where there haven’t been trout in years.”

For more information, visit fws.gov. Click here to see a list of all the projects in an interactive map.

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Josh Bergan is Fly Fisherman’s digital editor.