Lower Snake River Dams Revisited

Lower Snake River Dams Revisited                           

By Andy McCormick

Conservation Issues

Last month’s column on the potential benefits of breaching the four federal dams on the lower Snake River elicited a response that questioned those benefits and the need to breach the dams. The response led me to investigate this idea more thoroughly and I found a tremendous amount of information. This article is longer than usual, because these issues involved are complicated.

The Southern Resident population of Killer Whales (orcas) were declared endangered under the Endangered Species Act (ESA) in 2005. These orcas depend on Chinook salmon for the major part of their diet. The fall and spring/summer runs of Chinook salmon in the Snake River were declared threatened under the ESA in 1992. By 1999 the spring run of Chinook salmon was nearing extinction and was listed as endangered. All other Washington State salmon runs are considered threatened under the ESA.

In the past 30 years millions of dollars have been spent on recovery efforts and not a single salmon run has been recovered. If we had done a better job restoring salmon runs, it is possible that orcas might be doing better than they are now. What has happened? This summary will review the state of the Southern Resident Population of Killer Whales, the Chinook salmon runs, and the proposal to breach the lower Snake River dams.


Three pods of orcas make up the Southern Resident Population and are resident in Puget Sound in the summer months. During this these months they feed mostly on Chinook salmon that spawn in the Fraser River Watershed. In fall and winter, these orcas migrate to the Pacific Ocean and hunt for salmon north to SE Alaska and south as far as Central California. They have a more mixed diet through the winter, but feed on returning Snake/Columbia River Chinook in the spring at the mouth of the Columbia River. Recent analysis indicates three factors that are negatively affecting orcas. They are a lack of Chinook salmon, poor water quality in Puget Sound due to contaminants, and vessel presence and noise in Puget Sound. Their recovery depends on humans addressing these three problems.  


The Chinook (King) salmon is the largest of the salmon species and is a very fatty and nutritious food. It is highly preferred by orcas especially in spring as they fatten up after winter. The life cycle of Chinook salmon begins in cold freshwater streams. As smolts they migrate to the Pacific Ocean where they spend 3-4 years maturing in marine waters. Chinook that spawn in the Snake River watershed migrate to the ocean through the Columbia River and have spring and fall return runs. When fully grown, the salmon migrate back to the area where they originated to spawn and then die. Their death provides nutrients to an entire ecosystem in the interior of the continent. Historically through free running rivers and streams into Oregon, Idaho and Montana salmon runs produced millions of fish.

Historic Snake River salmon runs are estimated to have been between 416,000 to 650,000 fish. Since 1933, 50 large dams have been built in the Snake/Columbia Watershed. These include the three dams in the Hells Canyon Complex which have no provision for salmon passage resulting in the extirpation of salmon above this point on the Snake River. Salmon still populate the lower Snake River with help from humans to get them past eight dams, four on the lower Columbia River and four on the lower Snake River. The Snake is the Columbia’s largest tributary.

It is estimated that the fall Chinook run was down to 29,000 fish prior to the construction of the four lower Snake River dams. In the late 1970s hatchery fish were introduced annually to supplement the wild salmon runs. Since the year 2000 hatchery fish releases have increased dramatically and now dominate the runs. In the period from 2004 to 2014 the fall Chinook run averaged 89,000 fish, with 80% of these fish being hatchery-spawned Chinook. The wild-spawned Chinook totaled about 18,000 fish. For at least 20 years removal of the four lower Snake River dams has been proposed to help restore the Snake River spring and fall wild salmon runs.

This large-scale addition of hatchery-spawned fish accounts for about 80% of the salmon in the Snake River Watershed and there is some concern about the influence of hatchery-spawned Chinook on wild-spawned Chinook. The hatchery-spawned fish tend to be larger than wild-spawned fish and compete with wild fish for forage. The U.S. Fish & Wildlife Service report Salmon of the West acknowledges that hatchery fish have developed adaptations that make them different from wild salmon. The service is conducting cooperative research with federal, state, tribal, and public partners to use “locally adapted fish to optimize genetic fitness and reduce potential negative genetic or ecological interactions of hatchery fish with their wild counterparts.” The report notes that hatchery fish allow many parties to enjoy salmon while management discussions continue. However, the goal of the NOAA Fisheries recovery plan is for wild fish recovery.

The NOAA Fisheries Snake River Fall Chinook Recovery Plan, 2017 NOAA 2017 documents that the construction of the four dams on the lower Snake River not only blocked natural passage of salmon, but also inundated historical fall Chinook salmon spawning areas. The report also acknowledges problems caused by the dams: Salmon have difficulty finding fish ladders at the dams, water temperature increases behind the dams endangering migrating fish, spawning areas have been reduced, and the homing ability of fish is impaired. Other dangers for juvenile fish, both natural and hatchery, include slowed migration, increased mortality, injuries or stress due to dam passage, increased predation, and exposure to agricultural and industrial chemicals.


Beginning in 1962 the first of four federal dams, the Ice Harbor dam, was built. It was followed in 1969 by the Lower Monumental dam, in 1970 by the Little Goose dam, and in 1975 by the Lower Granite dam. The original purpose of the dams was to aid the transportation of crops, primarily wheat, to the sea. They are river-run dams, meaning water is not completely dammed, and produce some hydroelectric power. A BPA Fact Sheet published in 2009 reports that the dams are used primarily for peak power and comprise about 5% of the total Pacific Northwest power system. The dams also support some irrigation projects. They are not designed for flood control.

The Seventh Northwest Power Plan 7 (2017) from the Northwest Power and Conservation Planning Council discusses a potential shortage of energy in Washington after the year 2020, but it also acknowledges a problem of surplus energy generated from hydro systems during the spring runoff.

The Bonneville Power Administration (BPA) is a federal agency that manages the Federal Columbia River Power System for energy production and distribution including sales to utilities in Washington and other states. In spring when there can be a surplus of hydroelectric power Bonneville may have to sell power at low prices, thus reducing its revenue. This has caused financial problems for BPA. In addition to the surplus driving down prices, two other factors contribute. The expansion of wind power generation in Washington and California, where Bonneville sells power, is reducing the demand for surplus power from NW hydro systems. A third factor results from low prices for natural gas. Three new natural gas-fired power plants have been constructed in Washington since 2010.

Partially in response to this increase in alternative sources of renewable energy, the 7th Power Plan states that “acquiring energy efficiency is the primary action [of the planning council) for the next six years.” The plan emphasizes energy efficiency over increasing power production. One aspect of the proposal to breach the dams is based on a plan that will increase energy production from renewables to a point where the production from these dams is no longer needed. In April of this year, Energy Strategies conducted the Lower Snake River Dams Power Replacement Study and concluded that “a portfolio of renewable energy including solar, wind, energy, demand response, and storage” can replace the energy produced by the dams.   

In 2016  in a special report Southern Resident Killer Whales and the Snake River Dams NOAA 2016 opined that “the relative size of the Snake River salmon stocks compared to others on the West Coast means that increases in their numbers, whether from breaching dams or otherwise, would result in only a marginal change in the total salmon available to killer whales.” Relatively, the fall Chinook run on the Snake River is doing better than all other Chinook runs in Washington. Increasing the numbers of fish in the other runs is also important.

However, advocates from Save Our Wild Salmon take a different view and say that breaching the dams “would reduce dam-caused salmon mortality by 50% and restore productive access for wild salmon … to 5,500+ miles of contiguous, pristine, protected upriver habitat in northwest Oregon, central Idaho, and southeast Washington State. They predict that increasing the numbers of Chinook into this spawning area would show returns in greater numbers of Chinook in the Snake/Columbia system in two years.


Because orcas spend their summer in Puget Sound, the Salish Sea is another very important area supporting orcas and Chinook salmon. One objection to the focus on the Snake River dams is that it will distract people from important work being done for orcas in The Salish Sea. Advocates for orcas and salmon say we must work on both areas at the same time because orcas use different sources of Chinook salmon at different times of year.

The Northwest Indian Fisheries Commission report Northwest Treaty Tribes State of Our Watersheds 2016: Salmon Habitat in Decline has concluded the following. “At the 10-year mark of the Puget Sound Salmon Recovery Plan, a review of key environmental indicators for the Puget Sound basin shows improvements for water quality and removal of forest road barriers, but degradation in water quantity, marine shoreline habitat conditions and impervious surface areas.” They also address a shortage of staff at all levels and funding shortfalls to address the problems.

There are 16 Native American tribes that border the Salish Sea in the United States and each tribe submitted a report to full report. The individual tribal reports show marked decline in water quality (8 reports), an increase in water wells which can reduce the water table (10 reports), shoreline forage fish habitat where salmon and many bird species feed (13 reports), increasing impervious surface (more paving) (11 reports), and impassable culverts (5 reports). The reports acknowledge that restoration work is continuing to improve estuaries, some shoreline, forest cover, and riparian buffers. However, the overall sense of these reports is that habitat for salmon in Puget Sound is declining. The Governor’s Report State of Salmon in Watersheds 2016 agrees with the assessment that Puget Sound is losing salmon habitat faster than it can be restored. Much more must be done faster to improve habitat in Puget Sound.


The Governor’s report reviews the goals for salmon runs. It states that Puget Sound Chinook recovery and Upper Columbia River spring Chinook recovery are below goal and getting worse. Lower Columbia River fall and spring Chinook are not making progress. Only Snake River spring and summer Chinook are showing signs of progress, and Snake River fall Chinook is approaching the goal. These assessments count wild-born returning spawning fish. The ongoing problem is that despite 24 years on the endangered species list there is limited progress and Chinook runs overall are not meeting even survival goals, much less recovery goals. The spring Chinook run on the Snake/Columbia River is vital for orcas in the spring at the mouth of the Columbia River.

An advocacy coalition representing Defenders of Wildlife, National Resource Defense Council, National Sports Fishing Industry Association, Sound Action, and Wild Orca supports two actions to improve the spring Chinook run on the Snake River. The first is to increase water spill over the dams during out-migration to assist juvenile salmon to get over dams to the ocean. Currently only about 1% of smolt that leave the spawning area return as adults to spawn. Helping young fish to migrate is a way to prevent deaths from dam turbines, warm waters behind dams, predators, and collecting and barging fish around the dams.

The second is to breach the four lower Snake River dams by opening the earthen portion of the dams. This will open the Snake River salmon spawning habitat and reduce the number of dams fish must navigate by half. The four dams on the lower Columbia River will remain in place. Five federal court decisions have concluded that NOAA Fisheries, which is responsible for salmon recovery under the Endangered Species Act, has not thoroughly reviewed all measures to insure salmon recovery and the latest court order requires NOAA to write a new plan to include the Federal Columbia River Power System and its impact on salmon recovery. NOAA and other federal agencies have until 2021 to complete this analysis. It is not clear how well the orcas will do over the next two years.

There is opposition to breaching the dams from Eastern Washington interests and their needs for water and barging need to be addressed. Advocates for breaching point out that irrigation can continue, and crops are more often now transported by rail. The evidence in support of orcas and salmon points to the need to open the Snake River. In the meantime, salmon habitat in Puget Sound needs considerable work to help Fraser River Chinook recover.

We have an endangered killer whale depending for life on an endangered salmon, and to get them to recovery, we will need to give up some things to gain something else. It can be thought of as a different kind of wealth - a healthy ecosystem for orcas, salmon, and humans.


The Seattle Times reported on October 12 that Lolita, the last killer whale from Washington State still alive in captivity, will stay at the Miami Seaquariam. The U.S. Federal Court of Appeals of the Eleventh Circuit in a decision on October 9 rejected a petition brought by the Lummi Nation, People for the Ethical Treatment of Animals, The Animal Legal Defense Fund, and Orca Network to free the orca named Lolita and retire her to a sea pen in Puget Sound, where she could be fed live Chinook salmon, and be in home waters again in acoustic contact with her family. The court ruled that at her age, estimated to be 51, they could not find a threat of serious harm in her life at the Seaquariam, and thought she could not be moved to Puget Sound without being harmed. Lolita was captured at Penn Cove on Whidbey Island in 1970. Approximately one third of the members of the Southern Resident Population of Killer Whales was captured and shipped to aquariums and parks around the world. All but Lolita have died in captivity.