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SOS Blog

Save Our Wild Salmon

Hot Water Report 1


Welcome to Save Our wild Salmon’s Hot Water Report 2022.

During the summer, this weekly report will provide an update on real-time water temperatures in the lower Snake and Columbia River reservoirs via graphs and analyses, a summary on the highest weekly water temperatures 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 hear first-hand from scientists, Tribal members, fishing guides, advocates, and other experts about the challenges facing the Columbia and Snake rivers - and our opportunities to improve and restore them - in order to recover healthy, resilient fish populations and the 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. The longer and the higher these temperatures rise above 68°F, the greater the harm, including: migration disruption, increased metabolism, increased susceptibility to disease, reduced fecundity or reproductive potential (by reducing egg viability), suffocation (warm water carries less oxygen), and in the worst case - death.

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 re-establish cool water temperatures - or we will lose these species forever. Restoring a freely flowing lower Snake River by removing its four federal dams is likely our only 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 - Lower Snake and Columbia River Temperatures

Introduction: The daily mean temperature at the four reservoir forebays (immediately upstream from the dam) in the lower Snake River (above) and the lower Columbia River (below) for 2022 is represented with solid lines and their 10-year average (2012 - 2022) temperatures with dashed lines of the same color. The dotted line across the graph represents the 68°F “harm threshold” for adult and juvenile fish. Salmon and steelhead begin to 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 potential effects, including: increased metabolism, increased susceptibility to disease, reduced fecundity or reproductive potential, and/or death (see Issue 1 for more detailed information).

Discussion: Since April, temperatures in the lower Snake River and the lower Columbia River reservoirs have steadily moved upward. During April and May, trends have tracked closely with the 10-year average. In June, however, water temperatures dropped considerably below this average. This was good for cold-water species like salmon and steelhead, but now, temperatures have reached the 68°F “harm threshold” in the reservoirs on the lower Snake and Columbia River. Below, we present the highest temperatures for each reservoir on the lower Snake River.

A note on data information: 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. There is no available data for Lower Monumental 10-year average water temperature. Graphs and tables were assembled by SOS Staff.


Harmful water temperatures in the lower Snake River reservoirs: This week, on the lower Snake River, the Little Goose, Lower Monumental, and Ice Harbor Dams have peaked over the threshold (68 degrees). The reservoir behind the Ice Harbor reservoir registered the highest temperature at 69.98°F on July 23rd and July 25th and the Little Goose Dam registered the second highest temperature at 69.80°F on July 25th.

On the lower Columbia River, all reservoirs peaked over the 68 degrees threshold. The reservoirs behind the Bonneville and the John Day Dam registered the highest temperature at 69.26°F on July 25th.


dam.iceharbordamDefenders of the embattled lower Snake River dams (LSRD) claim that we can’t restore a free-flowing lower Snake River to recover abundant salmon and steelhead runs, while providing reliable power and meeting our clean energy goals.

Is this true? Can we restore salmon and still have reliable, climate-friendly electricity, or do we have to choose one or the other, but not both?

Let’s start by defining what the dams do (and don’t) contribute to meeting Northwest electricity demand. The four lower Snake dams have a nameplate capacity of 3,033 megawatts (MW), ostensibly enough to serve three cities the size of Seattle. But on an annual basis, they actually generate far less than that: just 888 average megawatts (aMW) – a 29.7% capacity factor (depending on siting, NW wind projects have a 35-50% capacity factor, NW solar about 25%). And the dams’ production of “firm power” – energy that can be generated even in years of exceptionally low stream flows -- is substantially less: just 438 aMW.

Why so low? Because the lower Snake dams are “run-of-the-river” dams, as they do not store water for power production (or flood control, for that matter). The LSRD produce the most power in the spring snowmelt season and much less in other seasons. In addition, climate change is creating challenges for the existing hydropower system. Warming temperatures mean more precipitation in the Northwest falls as rain rather than snow, which causes less, and earlier snowmelt that is needed to power the LSRD. Droughts are expected to increase in both frequency and magnitude which results in lower river flows causing less water to generate power from the dams, especially in summer.

Unfortunately, massive droughts, and warmer temperatures will become more common as climate change continues to advance and will continue to threaten both our fish and the reliability of our region’s power supply.

However, do we have enough clean energy available to replace the four lower Snake River dams’ energy services? Both computer modeling results and real-world evidence say that the answer is yes.

In 2018 Energy Strategies LLC, a respected mainstream energy consulting firm analyzed options for replacing the energy services of the lower Snake dams. Their study found that:

It is possible for a set of clean energy resources to replace the most important power attributes that the four LSR Dams are forecasted to contribute to the Northwest region. The level of wind, solar, energy efficiency, demand response, and battery storage required to achieve sufficient replacement, as defined by this study, is readily available in the region.1

They concluded that the cost would be little more than $1.25 on an average monthly residential power bill, and system reliability would be maintained or increased.

In 2022, Energy Strategies did an updated analysis of the issue that reaffirmed the 2018 findings but added that:

The study suggests that replacement portfolios will generate power at times when the region needs it the most, resulting in $69M - $131M million per year of energy value above and beyond what the LSR dams provide for the same time period. This result is heavily driven by the LSR dams generating most of their annual energy output during the spring runoff season when power prices are low and the region exports its excess energy.2

The resources in the Energy Strategies replacement portfolios are all “market-ready”, available in the 2024-2028 time frame. The resources selected were chosen from the Bonneville Power Administration’s “transmission queue” – specific projects with sponsors, sites and technology who have notified Bonneville that they will need transmission services when their project is acquired by a regional utility. The replacement portfolios selected only 12% of the resources in the queue.

Perhaps even more compelling evidence comes from the results of recent NW utility requests for proposals (RFP) seeking new energy and capacity resources.

In 2020 PacifiCorp issued an RFP for about 4,300 MW of energy and capacity resources
for delivery by 2024. Bids into the RFP totaled over 36,000 MW. PacifiCorp then selected a mix
of wind, solar and batteries totaling 4,000 MW.

In 2021 Puget Sound Energy issued an RFP for about 3,200 MW of energy and capacity to
be available to the utility in 2025. Bids into the RFP for wind, solar and batteries totaled about
18,000 MW, Puget will make a final selection later this year.

Each of these RFPs sought more energy and capacity than the combined capability of the four lower Snake dams and were each oversubscribed by 5-8 times. There are energy resources – today – that are far more capable to replace the energy services of the lower Snake dams.

Studies and real-world evidence all point towards adding a balanced mix of renewable resources, energy storage, and customer-side resources to replace the power from the lower Snake River dams. We have a unique opportunity to diversify our energy sources, invest in clean energy solutions like solar and wind power, increase energy efficiency and energy storage, and provide customer-side resources as well as develop more resilient solutions to protect and recover salmon and steelhead populations.

1. NW Energy Coalition: The Lower Snake River Dams Power Replacement Study (April, 2018)
2. NW Energy Coalition: Smart Planning Will Drive Replacing the Power from Lower Snake River Dams (February, 2022)


 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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