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SOS Blog

Save Our Wild Salmon

Hot Water Report 1


Welcome to Save Our wild Salmon’s Hot Water Report 2021. During the summer, this weekly report provides updates on real-time water temperatures in the lower Snake and Columbia river reservoirs via graphs and analyses, reports on the highest weekly water temperature at the forebay/reservoir of each dam, and the status of adult returns for different salmon and steelhead populations as they make their way back to their natal spawning grounds. We’ll share information from scientists, fishers, guides, advocates, and other experts about the challenges facing the Columbia and Snake rivers - and opportunities we have to restore healthy rivers and to recover abundant fish populations and the many benefits they deliver to the Northwest’s culture, economy, and ecology.

The once-abundant anadromous native fish populations that call the Columbia-Snake River Basin home are struggling to survive primarily due to multiple harmful effects caused by the system of federal dams and their reservoirs. The federal hydro-system creates conditions that harm and kill both juvenile and adult fish, including by elevating water temperatures in large, stagnant reservoirs, especially in the summer months. As cold water species, salmon and steelhead begin to suffer harmful effects when water temperatures exceed 68° Fahrenheit. The longer and higher temperatures rise above 68°F, the greater the harm, including disruption in their migration, increased metabolism, increased susceptibility to disease, reduced fecundity or reproductive potential, suffocation, and in the worst case - death.

These harmful hot water episodes above 68 degrees in the Columbia and Snake rivers are increasing in duration, frequency, and intensity. Our changing climate is making an already bad situation for the Northwest’s emblematic fish worse. Our region and nation must take urgent action to cool these waters or we will lose these species forever. Restoring a freely flowing lower Snake River by removing its four federal dams is our best and very likely only option for lowering water temperatures in this 140-mile stretch of river in southeast Washington State. Restoring the Snake River is one essential part of what must be a larger regional strategy to protect and rebuild healthy, abundant salmon and steelhead populations in order to benefit other fish and wildlife populations, including critically endangered Southern Resident orcas, to honor tribal rights, and to ensure prosperous communities across the Northwest.

Will you be on the river this summer? Do you have a story or photo you would like to share? Please send them to Martha Campos

The Hot Water Report is a joint project of the Save Our wild Salmon Coalition, Washington Sierra Club, Columbia Riverkeeper, Idaho Rivers United, National Wildlife Federation, Snake River Waterkeeper, Northwest Steelheaders, Defenders of Wildlife, and Endangered Species Coalition.

II. READING THE DATA - Lower Snake and Columbia River Temperatures

The daily mean temperature at the four reservoir forebays (immediately upstream from each dam) in the lower Snake River (above) and the lower Columbia River (below) for 2021 is represented with solid lines and their 10-year average (2011-2021) temperatures with dashed lines of the same color. The dotted horizontal line across the graph represents the 68°F “harm threshold” for adult and juvenile fish. Salmon and steelhead suffer harmful effects when water temperatures exceed 68° Fahrenheit. The longer temperatures remain above 68°F and the higher the temperatures rise above 68°F, the more severe the effects.

Fortunately, water temperatures have begun to drop but at this time they still remain high - and harmful - for salmon and steelhead in the lower Snake and lower Columbia River reservoirs: On the lower Snake River, the waters in the Ice Harbor, the Lower Monumental, and the Little Goose reservoirs continue to exceed the ‘harm threshold’ (68 degrees) this week. On August 25th, the Ice Harbor reservoir had a high mean temperature of 71.24°F and the Lower Monumental reservoir had a high mean temperature of 70.52°F.

On the lower Columbia River, current reservoir temperatures continue to exceed the ‘harm threshold’ (68 degrees). On August 25th, The Dalles and John Day reservoir had the highest mean temperature of 70.52°F. The Bonneville reservoir had the second highest mean temperature of 69.80°F on August 25th and August 27th. A note on the lower Snake River Water Temperature Graph: The mean water temperature data from these reports comes from the USGS Current Conditions for Washington State and the 10-year average water temperature data comes from the Fish Passage Center. USGS began recording water temperatures at Ice Harbor and Lower Monumental on June 16, 2021, Little Goose on June 19, 2021, and Lower Granite on June 18, 2021. Although we are not able to compare spring water temperatures to summer water temperatures, we can see June temperatures rising above the 10-year average and all water temperatures in the lower Snake River are above 60°F.


On the lower Snake River, all reservoirs registered high temperatures above 68°F for at least part of the past week. The reservoir behind the Ice Harbor Dam registered the highest temperature at 71.42°F - significantly above the level that coldwater fish require. Lower Monumental Dam’s reservoir had the second-highest temperature at 70.52°F.

On the lower Columbia River, all reservoirs registered high temperatures above 69°F for multiple days. The reservoir behind the John Day Dam had the highest temperature this week at 71.24°F. The Bonneville Dam had the second-highest temperature at 71.16°F.

Temperature data included in these reports come from the USGS Current Conditions for Washington State and the Fish Passage Center. Graphs and tables were assembled by SOS Staff.

IV. 2021 Snake River wild salmon and steelhead returns - so far.

As we near the conclusion of the Hot Water Report for 2021, this week we present the latest information regarding the status of native fish returns for Snake River (1) wild Spring/Summer Chinook, (2) wild steelhead, and (3) wild/natural sockeye. As part of this review, we will look at how the current numbers of returning adults compare to established recovery goals - the adult returns deemed necessary to recover these populations and remove them from the Endangered Species Act list.

In summary - Snake River salmon and steelhead populations have been in a steady decline for many years, they are returning this year at some of their lowest levels ever. They are teetering today on the precipice of extinction. Without immediate and meaningful conservation actions, we will lose these populations forever.

The health of these populations has plummeted over time from historic levels that were once in the hundreds of thousands or millions, depending on the particular population. The four federal dams and their reservoirs on the lower Snake River in southeast Washington State continue to be a main obstacle to recovery. The rising temperatures caused by these stagnant reservoirs and reductions in snowpack in recent decades due to climate change are contributing to lower survival and reproductive success for already endangered salmon and steelhead. As a result, wild Snake River Chinook, steelhead, and sockeye are much closer to extinction than established recovery goals. Despite spending billions of dollars on recovery projects, long-term trends for these populations have left these species at grave risk of extinction. Below, you will find the high-end recovery goals for wild Snake River salmon and steelhead that have been set to reflect the healthy run levels that returned to Idaho in the 1950s - before the dams were constructed. These goals represent self-sustaining, harvestable populations that currently available, high quality habitat in the Snake River Basin upstream from the dams could support. Restoring abundant populations will allow salmon to once again to play their essential role as a keystone species, feeding countless other animals and plants, and supporting Northwest cultures and economies. Restoring the lower Snake River through dam removal is our very best river and salmon restoration opportunity anywhere in the nation today. And, for the survival and recovery of Snake River populations, dam removal is an essential piece of a larger recovery strategy. Scientists predict it can regularly produce up to and more than a million adult salmon and steelhead entering the mouth of the Columbia River annually in the spring and summer months.

Snake River Wild Salmon Returns as of 8/24/2021

Spring/Summer Chinook

  • Endangered Species Act Status: Threatened (listed in 1992)
  • Historical Annual Return: Over 2 million
  • Recovery Goal: Escapement of 127,000 wild adults per year
  • Recent Returns: 7,062 (counted at the Lower Granite Dam)

Spring/summer chinook were once the Pacific Northwest’s most widely distributed and abundant salmon, numbering in the millions. The Salmon River alone produced 39 percent of the spring chinook and 45 percent of the summer chinook in the entire Columbia River Basin.1 Currently, an estimated 7,062 wild spring/summer Chinook have returned from the ocean to their upriver spawning grounds in Idaho.

In 2020, just 8,556 wild spring/summer Chinook returned to Idaho. Compared to the 4,152 wild Chinook that returned in 2019, this may seem like a strong improvement and a sign of a population on the right track. However, the oscillating nature of salmon returns means that variation from one year to the next is normal. The recovery goal for wild spring/summer chinook calls for a 10-year average of 127,000 returning fish. Notably, the 2020 adult return is less than 7% of this recovery target, and the 10-year average is just 11% of that target.


  • Endangered Species Act Status: Threatened (listed in 1997)
  • Historical Annual Return: Over 1 million
  • Recovery Goal: Escapement of 104,500 wild adults per year
  • Recent Returns: 440 (counted at the Lower Granite Dam)

Historic runs of steelhead to the Snake River Basin were estimated to be approximately one million fish annually.1 The Snake River and its tributaries produced 55 percent of summer steelhead in the entire Columbia River basin.1 However, wild steelhead returns have declined over the past years compared to their recovery goal of 104,500 wild steelhead returns per year. During the 2018-2019 run, only 8,287 wild steelhead returned to Idaho, just 8% of returns from the 1950s. The 10 year average for steelhead is 28,911, which is 28% of the recovery goal. Now, an estimated 440 of wild steelhead have returned from the ocean to their upriver spawning grounds in Idaho. Snake River steelhead are in critical decline today. Without urgent effective conservation measures, they will go extinct.


  • Endangered Species Act Status: Endangered (listed in 1991)
  • Historical Annual Return: Over 100,000+/yr to central Idaho’s high mountain lakes
  • Recovery Goal: 9,000 wild adults per year to the Stanley Basin
  • Recent Returns: 1 (counted at the Lower Granite Dam)

Sockeye salmon spawn in the glacial lakes of the Sawtooth Valley and, historically, a few other high elevation lakes in central Idaho.1 Historic runs to Idaho’s high mountain lakes used to be 100,000+ sockeye per year but have also severely declined over the years.1 In the early 1990s, there were no adult returns for sockeye salmon due to harmful conditions the lower Snake River dams produced and as a result the sockeye were first listed as an endangered species under the Endangered Species Act in 1991.2

The 10-year average for sockeye returning to the Stanley Basin in central Idaho is just 94 fish, 1% of the recovery goal of 9,000 wild sockeye per year. As of August 24, just 1 sockeye has returned to Idaho. This year, Idaho Fish and Game are trapping the sockeye that arrive at Lower Granite Dam and hauling them by truck to an Idaho Fish hatchery as a precautionary conservation measure, given the extremely low returns, resulting in 28 sockeye that have been trapped and hauled.3

Since the completion of the Columbia Basin’s last major dams on the lower Snake River in the 1970s, salmon survival rates have fallen far short of minimum levels every year. This trend continues today. Earlier this year, The Nez Perce Tribe’s Department of Fisheries Resources Management presented their latest analysis: “Snake Basin Chinook and Steelhead Quasi-Extinction Threshold Alarm and Call to Action.” This report shows that nearly half of the wild spring chinook populations in the Snake River Basin have crossed a critical threshold known as the Quasi-Extinction Threshold (QET), signaling they are nearing extinction and without immediate intervention, many will not persist. In addition, the river’s steelhead populations also face alarming threats to their continued existence. QET means 50 or fewer spawners on the spawning grounds for 4 consecutive years, and the QET also signifies that adult salmon abundance in a population nearing absolute extinction and the probability of recovery is low without substantial intervention.4

According to Dave Johnson, Manager of the Nez Perce Tribe’s Department of Fisheries Resources Management, the chinook salmon populations are “declining about 19% each year, and it is predicted that by 2025, 77% of spring and summer chinook populations in the Snake River Basin are predicted to be at or below the Quasi-Extinction threshold in the Snake River Basin.”5 The 77% of the natural-origin spring and summer chinook populations in the Snake River Basin will be closer to extinction within the next 5 years.4

The department also found that the summer steelhead populations are declining by approximately 18% each year and predictions show that by 2025, 7 (44%) summer steelhead populations are predicted to drop below 50 spawners.4

This year’s record low numbers of steelhead returns to the Columbia River and Snake River has caused Oregon and Washington’s Departments of Fish and Wildlife to adopt new immediate protective measures.6 ODFW announced that Oregon rivers connected to the Columbia system will be closed to steelhead retention from Wednesday, September 1st, to December 31st.6 Specifically, the lower Umatilla, Deschutes, and John Day Rivers including the Walla Walla River (starting at the Oregon-Washington border) will be closed to steelhead fishing.7

WDFW commissioners plan on shutting down steelhead fishing from the Snake River delta at Burbank to the Idaho-Washington border at Clarkston.6 The department has not yet released an official announcement regarding measures to protect wild steelhead runs on the Walla Walla River on the Washington side of the border.6

The Idaho Fish and Game Commission has not released the measures they plan to implement; however, “fisheries managers in Idaho are working on steelhead recommendations that will be forwarded to the Idaho Fish and Game Commission for consideration this week”8 Idaho Fish and Game officials stated they plan to implement measures that are “designed to protect threatened wild fish and ensure hatcheries meet spawning goals.”8

Unprecedented high water temperatures in the Pacific Northwest are putting Snake River salmon and steelhead runs at even greater risk and low returns of wild steelhead directly impacts local anglers, businesses, commercial, Tribal fishing economies, and communities across the Northwest.

Salmon and steelhead populations support thousands of fishing jobs throughout the Northwest; however, with the lower Snake River four dams in place, declining returns of these emblematic fish can be expected to continue. Relying on temporary protective measures is not enough to bring salmon and steelhead populations into abundance.

1. The Salmon Community’s View: The status of wild salmon and steelhead populations in the Columbia and Snake River Basin (2016)
I2. daho Fish and Game: Sockeye Salmon (2005)
3. SOS: A look at Snake River Wild Salmon & Steelhead Returns (August 4, 2021)
4. Snake Basin Chinook and Steelhead Quasi-Extinction Threshold Alarm and Call to Action (2021)
5. Salmon and Orca Summit 2021(July 8, 2021)
6. Union-Bulletin: Officials limit steelhead angling in Eastern Washington, Oregon as fish census plummets (August 30, 2021)
7. Oregon Department of Fish and Wildlife: Emergency fishing closures in Deschutes, other mid-Columbia tributaries begin Sept. 1 due to low steelhead returns (August 27, 2021)
8. The Lewiston Tribune: Officials plan to close steelhead fishing (August 28, 2021)


 Martha Bio picMartha Campos is the Hot Water Report Coordinator with Save Our wild Salmon this summer while she resides on Kizh/Tongva ancestral lands in California. Martha holds a BA from the University of California, Davis in Native American Studies (and two minors: Environmental Policy, Analysis, and Planning and Climate Science and Policy) and is a queer, non-binary person of color with ancestral roots in Mexico.


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