A 9th U.S. Circuit Court of Appeals case is likely to determine who will develop a plan for water temperature issues in the Snake and Columbia rivers, and how soon those plans should be made—and not whether those plans will be developed.

Columbia Riverkeeper, Idaho Rivers United, Pacific Coast Federation of Fishermen’s Associations, Snake River Waterkeeper, and The Institute for Fisheries Resources maintain that EPA holds that responsibility. They say the federal agency entered into an agreement years ago with the states of Washington and Oregon and agreed to issue total maximum daily loads, or TMDLs, for temperature in those rivers. They will ask the judges to uphold a U.S. District Court ruling from October ordering the agency to produce the plans within 60 days.

EPA appealed that ruling, arguing that under the Clean Water Act, states are responsible for issuing TMDLs and EPA is then tasked with approving them. While acknowledging the agreement with states, the agency said in its appeal that it never granted the request by states for it to issue TMDLs for temperature.

Riverkeeper attorney Miles Johnson told NW Fishletter that regardless of who prevails in the hearing, not having a TMDL for temperature is a clear violation of clean water laws. “The Clean Water Act still has an obligation for someone to produce a TMDL when our waterways are out of compliance,” he said. “If EPA won’t, or doesn’t look like they’re willing to do that in a meaningful time frame, we certainly will consider asking the states to step in and reassume the obligation to create TMDLs.”

Temperature in the lower Snake and Columbia rivers has long been an issue; one climate scientists say will only get worse with climate change.

“I think it’s as important as the wrangling over spill for juvenile fish passage,” Johnson said. “When you look at the Columbia and Snake rivers in July and August—and in September and June—it’s often over 68 degrees,” he noted. “We need to figure this out, and fast, or we’re going to start losing additional runs of fish in the Snake River,” he added.

Johnson said 68 degrees is widely recognized as the upper limit of safe water temperature for salmon and steelhead. It’s part of water quality standards in both Washington and Oregon, and backed up by studies, including EPA’s own work showing that when river temperatures rise above 68 degrees, salmon and steelhead experience difficulties migrating upstream.

“They kind of hunker down and then they expose themselves to stress and disease,” he said.

Save Our wild Salmon refers to 68 degrees as the “safe” threshold; below it is the “comfort zone” and above it is the “danger zone.” The organization uses data from temperature gauges set up in the reservoirs at eight lower Snake and Columbia river dams to track water temperature and produce a weekly Hot Water Report during the summer months.

Joseph Bogaard, executive director of Save Our wild Salmon, told NW Fishletter that he started tracking water temperature and producing a weekly report after an estimated 250,000 sockeye salmon died in the Columbia Basin when water temperatures surged during the adult migration in 2015. Using available data from government temperature gauges, the report is an effort to get the information to the public and to policymakers, he said.

“What used to be periodic occasional spikes over 68 degrees in the summer is now sustained water temperatures above that,” Bogaard said. “This year, we’ll probably have five weeks at least of sustained water temperatures above 68 degrees.”

The most recent Hot Water Report shows that water temperatures in both rivers have continued to rise, and for the first time this summer, daily temperatures at all eight reservoirs peaked above the safe threshold every single day of the last week in August.

Except for Lower Granite—which benefits from cool water releases from Dworshak Dam on the Clearwater River—temperatures at the dams have exceeded 68 degrees for between 36 and 48 days so far this summer. Lower Granite has gone above 68 degrees for 20 days, the report says. Water temperatures at all but Lower Granite’s reservoirs went above 70 degrees August, the report says.

“The longer temperatures remain above 68 degrees and the farther the temperatures rise above 68 degrees, the greater the harm, including increased energy expenditure, increased susceptibility to disease, reduced fecundity or reproductive potential, and/or death,” it states.

Bogaard said the higher water temperatures are largely caused by reservoirs, which, as stagnant pools, tend to warm from solar radiation.

Not everyone agrees.

Kurt Miller, executive director of Northwest RiverPartners, said there are competing studies about the impacts of Snake and Columbia river dams on water temperatures. In 2003, the EPA found that—depending on the circumstances—dams can increase water temperatures by up to 6 degrees, he said.

But another study done by the Pacific Northwest National Laboratory found that reservoirs tend to moderate temperatures in the summer. Because there’s less water in a river without reservoirs, it warms up faster during the hot summer months. “The unimpounded river warms up faster and has higher mid-summer temperatures than the impounded river, but it cools down more quickly starting in September,” the study says.

More recently, EPA concluded in a pre-draft analysis that climate change and dams are the dominant sources that impact water temperatures in the Snake and Columbia rivers, which are strongly influenced by air temperatures.

It also found that impacts from dams vary substantially by month and by river location. Overall, the analysis found, from July through September, the impact of Columbia River dams ranges from a decrease in water temperature of 1.44 degrees to an increase of nearly 4 degrees, while the Snake River dams increase temperatures by between 0.5 and 4 degrees.

Miller said RiverPartners understands the desire to cool water temperatures for fish, but is concerned that the federal dams will be asked to change operations to cool the river to temperatures that wouldn’t even be possible if the dams weren’t there. “What we’re afraid of, potentially, is that anti-dam advocates will try to create a standard that is impossible to meet, and use that as leverage for dam breaching or other things we don’t support,” he said.

In a list of the organization’s frequently asked questions RiverPartner notes that dams with large storage reservoirs can help mitigate warmer temperatures downstream. “Climate change is a major driver of dangerous temperatures that warm rivers. Pulling out carbon-free resources—like hydroelectric dams—may worsen the problem long-term,” it adds.

Johnson said that once TMDLs are issued, the real work will begin to figure out how to address them. “A TMDL is step one of a process for bringing the Columbia and Snake rivers back within Oregon and Washington’s water quality standards for temperature,” he said. “It’s going to identify the causes of temperature problems and how much reduction in temperature is going to be needed.”

After that, he said, “I think there is a big process ahead of us. I hope it will not take years. I don’t think, frankly, that Snake River salmon can afford that.”

K.C. Mehaffey covers fish issues for Clearing Up, and is editor of the NW Fishletter. She joined the NewsData writing team in February 2018. From lawsuits to scientific studies, she is enjoying the deep dive into the Columbia Basin's many fish topics.