Restoring rivers and waterways in Alaska is crucial for enhancing fish habitat and promoting ecological balance in the region.

restoring rivers

Story by Marian Giannulis

Alaska has a wide variety of fish habitats that are still healthy and connected. It’s the reason we have the strongest salmon runs on the planet and our trophy sportfish draw anglers from around the world. It’s why fishing and tourism are two of the largest drivers of the state’s economy. It provides Alaskans with nourishment, both through food and culture, from remote villages to the largest population centers. But there is trouble in fishing paradise.

Threats to Aquatic Ecosystems

Across the state, degraded and disconnected rivers and streams are limiting the range and populations of fish. Mining has straightened river channels, disconnected flood plains, and removed crucial substrate needed for spawning. Logging has removed streamside vegetation that provides important structure and shade. Hydropower projects have blocked off entire rivers. All have negative impacts on fish and wildlife.

Culverts: Barriers to Migration

Road construction has led to thousands of culverts that impede or block fish passage. The Alaska Department of Fish and Game (ADF&G) has rated over 1,300 culverts as “red pipes” that are deemed inadequate for fish passage. There are 3,100 fish-passage culverts monitored by ADF&G; which means 41% do not meet fish-passage standards. These red pipes fragment watersheds by blocking access to critical spawning and rearing habitat. They also restrict the flow of water in high water or flood events, which can lead to road washouts and other expensive infrastructure damage.

A dead pink salmon lays at the bottom of a “red pipe” culvert that blocked fish access into Cloudy Lake. © HDL Engineering

Declining Salmon Runs

restoring rivers

A new culvert on Cloudy Lake opened .93 upstream miles and 37 lake acres of key overwintering habitat for juvenile coho salmon. © HDL Engineering

These habitat impacts are easier to ignore when salmon are thriving, but now many salmon runs around the state are declining. There are a myriad of causes beyond degraded habitat contributing to these declines, including warming waters, ocean carrying capacity, increased rates of infection, and trawler bycatch. These declines emphasize the need for healthy, continuous habitat, to give fish the best chance possible.

The deck has been stacked against salmon in many ways, but we have the power to play an ace on their behalf: rehabilitating the freshwater habitat in which they spawn and rear. Restoring and reconnecting degraded waterways has a proven track record for benefiting fish. When the U.S. Forest Service restored a 1.5-mile stretch of Resurrection Creek, they observed six times as many Chinook salmon in the restoration area just one year after the project was completed. The numbers of pink- and chum salmon also increased exponentially, with each seeing over a 1,000% increase in the 10 years following construction. This project also benefited other wildlife. Harlequin ducks utilize new pool habitat and constructed log jams for nesting and shelter. Moose can once again safely cross the stream with their calves, after it was transformed from a rushing straight channel back to a naturally meandering stream.

The Power of Restoring Rivers and Waterways

restoring rivers

A hand-tool crew places a log into a logged stream in the Tongass National Forest. © Trout Unlimited

Restoration activities can take a variety of forms across Alaska, but all have the singular result: returning watersheds to their natural state. The same equipment that once damaged pristine rivers is used to right the wrongs of the past. By demolishing dikes and digging pools, channelized mining streams can meander once again. Large woody debris is placed in streams that run through logging areas. Undersized, failing culverts under roadways are replaced with much larger pipes that are embedded in natural streambed material. The rehabilitated hydraulic environment takes the form of cut banks where juvenile salmon can hide, gravel bars ideal for spawning, and deep pools where fish can feed and hide.

Increased Flood Resilience and Economic Benefits

The benefits of restoration are felt well beyond the natural world. Projects are putting local communities to work with engineers contracted for survey and design, materials sourced from local businesses, and construction firms and heavy-equipment operators building the projects. Restoration projects also enhance communities’ resilience to extreme weather events. Naturally functioning streams and appropriately sized culverts are less likely to flood towns and wash out roads. These projects make communities safer and provide more abundant fish-and-wildlife resources.

restoring rivers

Heavy equipment stages logs in the Resurrection Creek restoration project. © Trout Unlimited

Funding for Restoring Rivers

There were two recent funding sources that greatly increased the ability to carry out this work. The 2021 Bipartisan Infrastructure Law and the 2022 Inflation Reduction Act both brought once-in-a-generation investments for fish-habitat restoration. Federal agencies are now putting those dollars to good work across Alaska through partnership with cities, boroughs, Tribes, and non-profits. The scope and scale of restoration work across Alaska will continue to increase in the coming years. We look forward to bringing you more stories of communities and partners coming together to care for fish with benefits to fish, wildlife, and communities.

Trout Unlimited’s mission is to protect, reconnect and restore North America’s cold-water fisheries and their watersheds. Learn about our work in Alaska at Marian Giannulis is the Alaska Communications & Engagement Director for Trout Unlimited.

Restoring rivers and waterways is just one way that anglers can contribute to the cause. Read Fish Alaska’s Conservation Blog for more.