Fish Tale

Fish Tale

The Bonneville Dam, which spans the Columbia River between the U.S. states of Oregon and Washington, has affected fish populations, but now organizations are attempting to lessen its impact on the environment.


3 - 12


Earth Science, Engineering, Geography, Physical Geography, Physics

NGS Resource Carousel Loading Logo
Loading ...
Leveled by
Selected text level

The Columbia River used to be a wild river. It is 1,954 kilometers long (1,214 miles). The river winds through the U.S. states of Oregon and Washington and into Canada.

The Columbia River was once full of salmon, a kind of fish. Now, the river is much calmer. It has 14 dams on it. A dam is like a wall that slows the water. As the water passes through it, it turns blades inside. This creates electricity. The dams have turned the river into something more like peaceful lakes and ponds.

The dams on the Columbia create more than half of the area's electricity. The dams also make the river easier for boats. They allow boats to go from the Pacific Ocean all the way to Idaho. That is about 750 kilometers (about 465 miles).

Salmon Need To Get Upstream

The dams have made trouble for the river's ecosystem. The salmon have been hurt.

The Columbia was once a fast-moving waterway. It had a very large population of fish. Salmon need fast, cold water. The dams carved the river into smaller pieces. The water moves slower and is warmer. The dams make it harder for the salmon to swim upstream.

Fish Ladders

Fish ladders were built at many of the dams. They allow salmon to get past the dams. The fish ladders are like steps and the water flows down them. They create a bunch of shallow waterfalls. The waterfalls let the fish get upstream to lay eggs.

Once the fish are born, they head back downstream. The dams' blades have been changed. Now they are less harmful to fish. A path was also added that allows the fish to swim around the blades.

Sometimes, water is spilled over the top of the dams. This makes the river flow the way it used to. The dams create less electricity this way, but it is better for the fish.

Sea Lions In The River?

Sea lions travel up the Columbia River from the ocean. They eat the salmon there. To protect the salmon, U.S. Army engineers and the states of Washington and Oregon use firecrackers and rubber bullets. They try to scare away the sea lions.

Fish Cam!

The Bonneville Dam Fish Camera shows a new photo every 20 seconds. You can watch the fish swimming through.

Fast Fact

Fish Cam
See what fish are swimming through the Bonneville Dam. The Bonneville Dam Fish Camera updates with a new photo every 20 seconds.

Fast Fact

River Writer
During the 1930s, American singer and songwriter Woody Guthrie was hired by the Bonneville Power Administration to write songs promoting the hydroelectric dams on the Columbia River. During the month-long job, he penned classics including "Roll On Columbia," "Grand Coulee Dam," and "Pastures of Plenty."

Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.

Stuart Thornton
Jeannie Evers, Emdash Editing, Emdash Editing
Kara West
National Geographic Society
Last Updated

October 19, 2023

For information on user permissions, please read our Terms of Service. If you have questions about how to cite anything on our website in your project or classroom presentation, please contact your teacher. They will best know the preferred format. When you reach out to them, you will need the page title, URL, and the date you accessed the resource.


If a media asset is downloadable, a download button appears in the corner of the media viewer. If no button appears, you cannot download or save the media.


Text on this page is printable and can be used according to our Terms of Service.


Any interactives on this page can only be played while you are visiting our website. You cannot download interactives.

Related Resources