The Klamath Hydroelectric Settlement Agreement calls on the secretary of the interior to make a decision on whether to remove four Klamath River dams based on a foundation of scientific findings. That is why more than 100 experts on my team, including biologists, engineers, economists, hydrologists, and others, have been developing and sharing new scientific information for the past two years.
In developing this information, my team used the universal principles of the scientific method to produce 50 new reports: literature review, hypothesis (assumption) testing, data collection and analysis, and publication of peer-reviewed, publicly available reports which are available at Klamath
Restoration.gov. Our team summarized these findings in an overview report that received a second layer of peer review from six independent experts.
We also obtained independent expert critiques of some existing reports, convened four independent science panels to provide points-of-view separate from those of federal scientists, and obtained valuable input during 25 public meetings since 2010.
At these public meetings, people brought forward new information, topics for investigation, and their scientific assumptions. This was an open, transparent, and useful public process, and our reports are better because of it. During our scientific analyses, we investigated many assumptions, including those raised by the public. Some assumptions proved to be supported by facts, while other assumptions proved to be inaccurate or incorrect.
Dr. Paul Houser, in a series of speaking engagements last month in the Klamath Basin, discussed many scientific assumptions that our analyses have shown to be inaccurate or incorrect. Although space won’t allow a response to each of these inaccurate assumptions, responding to a handful of the more important ones is warranted.
Dr. Houser suggested that the federal engineers didn’t adequately study whether Iron Gate Dam would fail during removal. The engineering analysis of Iron Gate Dam removal was rigorous, the detailed plan fully describes the process to safely remove this large earth-fill dam with a clay core, and this plan underwent multiple layers of peer review.
Dr. Houser stated that “the devastation of the lower Klamath from all that sediment coming out is between one and three feet of the river channel, 150 feet wide, being covered with silt all the way down to the ocean.” This is incorrect. Sediment-transport modeling shows that dam removal would release 5.4 million to 8.6 million cubic yards of reservoir sediment. About 85 percent of this sediment is silt and clay that would be readily transported to the ocean by winter flows during reservoir drawdown. Very little of this sediment would remain in the river channel.
Dr. Houser stated that the “reservoir sediments are quite toxic” and are “high in phosphorus and probably quite a few other chemicals that have been banned for years.” Findings from our study, and an independent study in 2006, are contrary to these conclusions. An analysis of over 500 chemicals in 77 sediment cores did not show high concentrations of toxic chemicals. Chemical concentrations are below “Critical Guidelines” for sediment disposal and thus these reservoir sediments could be safely released downstream if dams were removed.
Dr. Houser stated that sediment release “will devastate fisheries for at least a year or two.” Our analysis shows that a winter release of sediment in a single year, even under a “worst-case” condition (dry year), would result in less than 10 percent basin-wide mortality of coho and chinook salmon, and 20 to 30 percent basin-wide mortality of steelhead. Proposed mitigation measures would decrease this short-term mortality. In the long term, dam removal would benefit all three fish populations.
Dr. Houser stated “one of the things I do know is salmon were introduced in the Klamath in about 1895, intentionally, by people,” suggesting that coho or chinook salmon are non-native. Dr. Houser may have been referring to a plant of coho salmon in 1895 in the Trinity River Basin that was overseen by the U.S. Commission on Fish and Fisheries. This was an effort to replenish over-harvested native Klamath coho runs with stocks from nearby streams; it was not an introduction of a nonnative species.
Dr. Houser has never spoken with me regarding these scientific concerns, or any other scientific concerns regarding the accuracy of our studies. As senior scientist on this project, I am committed to bringing accurate, objective, fact-based scientific findings forward for the secretary’s decision.
If my team has erred in an analysis, missed a valuable information source, or failed to investigate an important assumption or concern, my science team stands ready, as always, to evaluate new ideas and information sources, and to correct any errors. This decision is too important to leave any stone unturned.
Dennis Lynch has been a hydrologist with the U.S. Geological Survey for 32 years, including studies in the Klamath Basin for 17 years. He is the lead federal scientist overseeing the science and engineering process for the secretary of the interior on Klamath River dam removal.