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Save Our Wild Salmon

Hot Water Report 1


Welcome to the Hot Water Report 2022, Issue 11, our final issue for this summer!

This summer, we’ve provided updates on real-time water temperatures in the lower Snake and Columbia River reservoirs via graphs and analyses, a report on the highest weekly water temperature at the forebay/reservoir of each dam, and the status of adult returns for the different salmon and steelhead populations as they return to their natal spawning grounds. We heard first-hand from scientists and other experts about challenges facing the Columbia and Snake rivers - and the opportunities we have to restore health to these rivers, and help recover healthy, resilient fish populations and the many benefits they deliver to the Northwest’s culture, economy, and ecology.

The once-abundant anadromous fish populations of the Columbia-Snake River Basin are struggling to survive today in large part due to multiple harms caused by the system of federal dams and 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 in the summer months. These cold-water fish begin to suffer harmful effects when water temperatures exceed 68° Fahrenheit.

Today, these harmful hot water episodes above 68°F in the Columbia and Snake Rivers are increasing in duration, frequency, and intensity. Our changing climate is making a bad situation for the Northwest’s iconic fish worse. Our region and nation must take urgent action to maintain cool water temperatures - or we will lose these species forever. Restoring a freely flowing lower Snake River by removing its four federal dams is our only feasible option to address high water temperatures in this 140-mile stretch of river running through southeast Washington State. Restoring the Snake River is one essential element 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 uphold our nation’s promises to Native American tribes, and to ensure prosperous communities across the Northwest.

The Hot Water Report 2022 is a joint project of the Save Our wild Salmon Coalition, Columbia RiverkeeperAmerican Rivers, Endangered Species Coalition, Environment Washington, Idaho Conservation League, Idaho Rivers United, Idaho Wildlife Federation, National Resource Defense Council, National Wildlife Federation, Nimiipuu Protecting the Environment, Northwest Sportfishing Industry Association, Sierra Club, Snake River Waterkeeper, Spokane Riverkeeper, Wild Orca, and Wild Steelhead Coalition.

II. READING THE DATA - Highest Water Temperatures on Lower Snake and Columbia River in 2022

This year, we experienced another summer of hot water temperature in the lower Snake River and the lower Columbia River. From mid-July to September, all four lower Snake River’s reservoirs had waters above the 68°F “harm threshold” for adult and juvenile fish. Salmon and steelhead begin to suffer harmful effects when water temperatures exceed 68°F.

The longer temperatures remain above 68°F and the higher the temperatures rise above 68°F, the more severe the potential effects to salmon and steelhead, including: migration disruption, increased metabolism, increased susceptibility to disease, reduced reproductive potential (by reducing egg viability), suffocation (warm water carries less oxygen), and in the worst case - death. Specifically, as temperatures reach 70°F, salmon start to form fungus on their bodies and are more susceptible to diseases. At 71-72°F, salmon stop migrating and at 73°F, salmon die (see this 2-minute video from National Wildlife Federation for more information).

Hot Water Temperatures in the lower Snake River: On July 14, 2022, the Little Goose reservoir was the first to reach 68°F and registered above 68°F for 48 days. On August 19, 2022, the reservoir behind the Ice Harbor Dam registered the highest temperature we have seen this summer – 72.32°F. In addition, the Ice Harbor reservoir had temperatures reaching above 68°F for 46 days.

The Lower Granite Dam’s reservoir had the second highest temperature of 71.96°F on August 31, 2022, and the reservoir registered above 68°F for 26 days. Lastly, the Lower Monumental reservoir reached a high temperature of 70.88°F on multiple days in mid-August.

By restoring this 140-mile stretch of the lower Snake River through dam removal, computer models show that, while temperatures in a freely flowing river may spike above 68 degrees periodically, they will quickly return to the cool temperatures that salmon and steelhead need to survive and migrate. A free-flowing lower Snake River would not absorb the same amount of solar radiation. Considerably cooler waters deliver big benefits to migrating juvenile and adult salmon and steelhead populations—leading to increased survival and reproductive success (see Issue 4 for more information on computer models showing the improvement of water temperatures without the lower Snake River dams). 

Hot Water Temperatures in the lower Columbia River: The water temperatures in the lower Columbia River gives us an in-depth look at the lethal conditions and temperatures that Snake River salmon and steelhead must migrate through. Endangered Snake River salmon and steelhead have to cross eight dams and reservoirs to reach the ocean and then again as they return to their spawning grounds. In addition, the dams and their hot water reservoirs can kill up to 70% of out-migrating Snake River juvenile fish before they ever reach the ocean.

Dave Johnson, Department Manager of the Nez Perce Tribe’s Department of Fisheries Resources Management, recently stated, "The fish evolutionarily are developed to make it down to the ocean in a certain amount of time. We've extended that period of time to a month [with the four lower Snake River dams in place] so they run out of reserves, they run out of their food by the time they reach the ocean” (see Issue 6 for more information).

As we see from the “Highest Water Temperatures on the Lower Columbia River” table above, the John Day reservoir reached a high temperature of 73.04°F on August 29, 2022. For endangered Snake River salmon and steelhead, the dams and the reservoirs have extended and changed their migration journey and continuously change water temperatures as the summer progresses.

A note on data information: The water temperature data from these reports comes from the USGS Current Conditions for Washington State. Tables were assembled by SOS Staff.

 III. A Look at Snake River Wild Salmon & Steelhead Adult Returns as of September 14, 2022

The Snake River's anadromous fish populations have been on a steady downward trajectory across the last several decades. These salmon and steelhead face multiple obstacles, including dangerously hot water in the summer months in the Snake River reservoirs. Below, we present background information on and current status of native fish returns, including (1) wild Snake River Spring/Summer Chinook, (2) wild steelhead, and (3) wild/natural sockeye. We will also look at how the historical and 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 - since the four lower Snake River dams were built, over 60 years ago, Snake River salmon and steelhead populations have been in a steady decline. Even before the dams were built, it was projected that lower Snake River dams would cause salmon and steelhead to go extinct. Each year, these fish return (far) below the recovery goals necessary to remove them from the Endangered Species Act list. Without immediate and meaningful conservation actions, scientists predict we will lose these populations forever.

(i) Snake River Spring/Summer Chinook:

  • Endangered Species Act Status: Threatened (listed in 1992)
  • Historical Annual Return: Over 2 million1
  • Recovery Goal: Escapement of 127,000 wild adults per year
    Estimated 2022 Returns: 15,678 (estimated as 20% of total run in season)
  • Analysis: 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 15,678 wild spring/summer Chinook have returned from the ocean to their upriver spawning grounds in Idaho.

(ii) Snake River Steelhead

  • Endangered Species Act Status: Threatened (listed in 1997)
  • Historical Annual Return: Over 1 million1
  • Recovery Goal: Escapement of 104,500 wild adults per year
  • Estimated 2021/2022 Returns: 10,998
  • Analysis: An estimated 10,998 wild steelhead have returned from the ocean to their upriver spawning grounds in Idaho in 2021/2022, which is well below the 10-year average of 22,735 and the recovery goal of 104,500 wild steelhead adults per year.

(iii) Snake River Sockeye

  • Endangered Species Act Status: Endangered (listed in 1991)
  • Historical Annual Return: Over 100,000+/yr to central Idaho’s high mountain lakes1
  • Recovery Goal: 9,000 wild adults per year to the Stanley Basin
  • Estimated 2022 Returns: 39 wild/natural-origin sockeye returned to the Stanley Basin 
  • Analysis: Historic runs to Idaho’s high mountain lakes used to be over 100,000+ sockeye per year but have also severely declined over the years.1 The 10-year average for sockeye returning to the Stanley Basin in central Idaho is just 80 fish and a recovery goal of 9,000 wild sockeye per year. Only 39 wild adult sockeye salmon survived to swim into their spawning grounds in the Stanley Basin in central Idaho after struggling past eight dams and warm and stagnant reservoirs downstream.

Given the current returns for wild Snake River chinook, steelhead, and sockeye, these fish are much closer to extinction than recovery. Snake River salmon and steelhead are on the brink of extinction today. 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. Snake River salmon and steelhead populations have been in a steady decline for many years; they are returning each year below their historical and recovery levels.

This summer, current salmon and steelhead returns are higher than those of the past 5 years as these fish encountered suitable water temperatures in the lower Snake River reservoirs prior to mid-July. However, recent heat waves caused temperatures to rise above 68°F – causing migration disruption and dangerous water conditions for salmon and steelhead. Restoring a freely flowing lower Snake River by removing its four federal dams is our only option to address high water temperatures and their impacts on wild salmon and steelhead, as well as recovering salmon and steelhead from extinction.

In the Hot Water Report Issue 6, we asked Jay Hesse, Director of Biological Services of the Nez Perce Tribe’s Department of Fisheries Resources Management, about this year’s current salmon returns:

“The increase in Snake River basin natural-origin spring/summer returns occurring this year (2022) is welcomed and consistent with our expectations for improved survival under good ocean conditions and high spill hydro-operations. However, it is important to understand that while the 2022 return is an improvement over recent years, abundance remains precariously low and well below criteria for Endangered Species Act-delisting - let alone our goals representing healthy and harvestable status.”

In addition, the Nez Perce Tribe’s Quasi-Extinction Threshold Analysis indicates that wild spring Chinook and steelhead populations in the Snake River Basin have crossed a critical threshold known as the Quasi-Extinction Threshold, signaling they are nearing extinction. And without immediate intervention, within the next 3-4 years, many may not persist.

A note on data information: The Snake River Wild Salmon returns data comes from the Fish Passage Center and Idaho Department of Fish and Game. Tables and graphs were assembled by Idaho Rivers United Staff.

 IV. Urgency To Restore The Lower Snake River

1sockeye.web 2

With U.S. Senator Patty Murray and Washington State Governor Jay Inslee's long-anticipated final Lower Snake River Dam Benefits Replacement Report and recommendations, we’re entering a critical new phase of work to protect and recover endangered Snake River salmon and steelhead populations and aid endangered, salmon-dependent Southern Resident orcas.

Senator Patty Murray and Governor Jay Inslee’s recommendations include this essential conclusion: The science is clear that – specific to the Lower Snake River – breach of the dams would provide the greatest benefit to the salmon. Salmon runs in the Lower Snake River are uniquely impacted by the dam structures relative other watersheds, and the waters of the Lower Snake River have unique potential for robust aquatic ecosystem and species recovery.”

Sen. Murray and Gov. Inslee announced key action items for the Snake River as one part of a larger set of important priorities and next steps, for state and federal governments working with Tribes and stakeholders to develop and implement a comprehensive regional solution to restore this historic river, protect and rebuild abundant salmon populations, uphold our nation’s promises to Tribes - and meet the needs of communities.

Our way forward – to plan and implement (i) the replacement of services and (ii) the removal of the lower Snake River dams – will require significant collaborative planning, policy, advocacy, and state and federal investments. With salmon and steelhead populations and the Southern Resident orcas struggling for survival today, immediate and sustained action is essential.

1. The Salmon Community's View: The Status of wild salmon and steelhead populations in the Columbia and Snake River Basin (2016) 

Hot Water Report 2022

Throughout our 2022 Hot Water Reports, we have identified key solutions and strategies to salmon recovery and restoring the lower Snake River. To protect, restore, and reconnect the freshwater habitats that salmon and steelhead depend upon.

View each of the Hot Water Reports here: HOT WATER REPORT– COMPILED.


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, nonbinary person of color with ancestral roots in Mexico.



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