Featured News, Siskiyou

Sediment Test Selected For Klamath River Lake Sediments Is Least Sensitive Available – Studies Show

Imagine for the moment you have a problem. You have a few dams with lakes behind them that have been accumulating and concentrating toxins and heavy metals for decades into their sediments. And you want to be able to remove the dams and send those toxic sediments down a wild and scenic river. What to do?

Arguably you find the best science money can influence, design the study to provide the desired outcome, and instead of using the most sensitive testing methods to detect levels and impacts of the toxins in the sediments, your hand-picked scientists use the least sensitive standard testing protocol, which according to peer-reviewed published *study, is, ‘elutriate sediment testing‘. The key study used to support sending polluted clay sediment down the Klamath River used elutriate sediment testing.

And in your report on the testing, you would of course include lots of disclaimer language like; ‘assumed’, ‘expected’, ‘believed’, ‘calculated’, ‘estimated’, and so on, along with the use extensive scientific terminology, conversion metrics and complex graphs filled with acronyms to bamboozle and discourage any review of the study by the vast majority of people.

But what is the best and most sensitive sediment testing protocol? According to several peer-reviewed published studies, the best methodology is bulk sediment testing.  Bulk sediment testing should have been utilized to get a full picture of the extent of the toxicity of the lake bed sediment.  

It seems given what’s at stake, namely the health of humans, the wildlife and aquatic life in the entire Klamath River ecosystem as well as the coastal ecosystem, you’d want the very best available testing protocols in place, right?

*Comparison of bulk sediment and sediment elutriate toxicity testing method [1]


“Numerous methods exist for assessing the potential toxicity of sediments in aquatic systems. In this study, the results from 10-day bulk sediment toxicity test methods using Hyalella azteca and Chironomus tentans were compared to results from 96-h Pimephales promelas and Ceriodaphnia dubia renewed acute toxicity tests conducted using elutriate samples prepared from the same sediments. The goal of the study was to determine if the results from the elutriate tests were comparable to those obtained from the bulk sediment tests. Of the 25 samples analyzed, 16 were found to be toxic to at least one of the species tested, in either elutriate or bulk sediment tests. The C. tentans 10-day bulk sediment test was the most sensitive, with 12 sediment samples exhibiting toxicity to this species, whereas the H. azteca bulk sediment test and C. dubia 96-h elutriate test were the least sensitive, exhibiting toxicity in only 7 of the 25 sediments tested. The P. promelas elutriate test found 8 of the 25 sediments to be toxic. Based on the total number of sites found to show toxicity, results from testing indicate 96-h elutriate tests show a level of sensitivity comparable to 10-day bulk sediment tests in assessing toxicity quantitatively. However, the methods did not always find toxicity at the same sites, suggesting that the ability of elutriate tests to predict toxicity (quantitatively) is not statistically correlated with bulk sediment methods. This would indicate that a suite of toxicity test methods would provide the most complete measure of site condition; however, in circumstances where bulk sediment testing is not feasible, elutriate tests can provide a practical and credible alternative for toxicity assessment.” [1] (additional supporting references; 2,3,4,5,6).

The simple truth is, the clay sediments in the now exposed lake bottoms of Boyle, Copco and Iron Gate Lakes are filled with various toxins that Siskiyou County doesn’t sample!  Rather, the county takes samples from the Klamath River starting west of I-5 and continuing further west.  In their baseline study (pre-dam removal), they took a sample below Iron Gate Dam and another closer to Hornbrook with the rest taken west of I-5, but the follow up sampling post dam removal were all taken west of I-5.  Why didn’t they take samples below Iron Gate Dam and near Hornbrook after the dams were removed?

Contrary to the heavily cited *study (*PDF attached at bottom of article) prepared for the Department of Interior by CDM Smith and Stillwater Sciences, the remaining quantities of sediments in the lake bottoms exceed what they cited in their study.  In fact, that questionable study suggests that all the sediments in the lakes would be washed out to sea. *Screening-Level Evaluation of Contaminants in Sediments from Three Reservoirs and the Estuary of the Klamath River, 2009-2011

But we must now ask, how is it that the majority of these toxic clay sediments actually are still remaining in the lake bottoms, contrary to what was predicted by CDM Smith and Stillwater Sciences, and are now being planted by KRRC, which means, they didn’t go out to sea during the initial sediment release, which resulted in a River of Death.

More about the clay sediments here: Dam Removal Destruction – Gas bubble disease – Part IV

On February 13, 2024 during recorded testimony to the Siskiyou County Board of Supervisors, Mark Bransom CEO of the Klamath River Renewal Corporation (KRRC) stated there was a total of 17-20 million metric yards of sediments in the lake bottoms, and they they released about 5-7 million metric yards of toxic sediments into the main-stem of the  Klamath River on January 23, 2024. 

Using Mr. Bransom’s math, there may be as much as 15-million metric yards of polluted clay sediments remaining in the lake bottoms, contrary to what was ‘expected’ to happen as cited in the CDM Smith/Stillwater Sciences study provided to the Department of Interior. KRRC went off their highly published, socialized and celebrated Plan to dewater the lakes over two months, and instead drained the lakes in just a few days. And KRRC did that release of toxic clay sediments into the Klamath River just a week before the United States Geologic Services (USGS) released their newest sediment and water sample tests on the Klamath Basin.

This most recent USGS study was conducted from 2018-2022 and completed in Sept of 2022. Yet interestingly, was not released publicly until a week after the release of 5-7 million metric yards of toxic clay sediments into the Klamath River by KRRC.

This vitally important USGS sediments report was not released to the public until after the reservoirs were drained.  

That USGS data is found online (Excel Spreadsheet & PDF) at this link: https://www.sciencebase.gov/catalog/file/get/6585c75fd34eff134d4354d3

The attached PDF titled, ‘Screening-Level Evaluation of Contaminants in Sediments from Three Reservoirs and the Estuary of the Klamath River, 2009-2011’ was prepared for U.S. Department of the Interior Klamath Dam Removal Water Quality Sub Team Klamath River Secretarial Determination by CDM Smith, Sacramento, CA, with assistance from Stillwater Sciences Berkeley, CA.That study cites the presence of PCBs, DDT, Chromium, Arsenic, Aluminum, Lead, Dioxin, Furan, Copper among others listed, in some cases, at questionable or unsafe levels for humans and aquatic life.

And there are numerous disclaimer statements made throughout that document, such as:

 ‘assumed’, ‘expected’, ‘calculated’, ‘estimated’, ‘believed’, etc. These terms of disclaimer are topped-off with a general theme stated in some conclusions that ‘expectations’ are that the toxins found in the sediments will be ‘diluted’ by the water of the Klamath River, its tributaries, and eventually by the ocean, thereby providing what they seem to suggest is the solution to potentially minimize risks to human, aquatic and terrestrial animals.  
In other words, they are selling the old failed and reckless adage, ‘dilution is the solution for pollution’. 
Basically, the authors of that study, which is heavily cited

 as key supportive study to dam removal and the arguable disposal of toxic sediments into a sensitive ecosystem, offer their paper as an argument that the toxins in the sediments are not all that bad, and not an issue since they will be diluted by the tributaries of the Klamath River and eventually washed out to sea.  

However, as we see from the visual empirical evidence at hand in the Klamath River below Iron Gate Dam, now a River of Death, massive amounts of sediments have clung to the Klamath River bottom along its entirety, covering the salmon and trout spawning beds (gravels) and is many feet deep in most locations. Some of the empirical results to-date are consistent with the written testimony and concerns of Dr., Paul Houser in 2012, who was fired as the Science Integrity Officer by the Department of Interior in 2012, arguably for disagreeing with the politically driven dam removal narrative.

Dr. Houser wrote: [7]“Mr. Lynch disagrees with my concerns that the released sediments may be harmful to fish, and may have a significant impact for 1-2 years.  The draft EIS/EIR states “…the short-term (<2 years following dam removal) increases in SSCs [suspended sediment] in the lower Klamath River and the Klamath Estuary would be a significant impact.” Water quality and reservoir sedimentation in the Klamath basin are very complex issues.  While a 2011 DOI report did show that the reservoir sediments have toxic elements below most guidelines, the upper basin is well known to have water and sediment quality issues, and these sediments are being deposited in the reservoirs.  A 2006 PacifiCorp study concludes that the absence of the project reservoirs would exacerbate water quality impairment by reducing dissolved oxygen and promoting growth of algae.Water quality issues above the PacifiCorp dams may be amongst the most significant risks to successful river restoration; these water quality issues should be mitigated prior to dam removal.”

Now cometh Siskiyou County:

Klamath River water quality deemed unsafe, Siskiyou Health Division says

Bottom Line:  
Citizens of Siskiyou County must demand that the Siskiyou County Board of Supervisors declare an Emergency, requesting immediate EPA oversight of the removal and safe relocation of the toxic lake-bottom sediments that are slated to be planted; and, at the minimum provide financial aid to citizens impacted by water quality issues, including but not limited to funding for citizens who have wells near the river for ongoing periodic domestic well testing for toxins for a period of 2-years.


  • 1. Comparison of bulk sediment and sediment elutriate toxicity testing methods Herman J Haring, Mark E Smith, James M Lazorchak, Philip A Crocker, Abel Euresti, Melissa C Wratschko, Michael C Schaub
  • 2. An interlaboratory comparison of sediment elutriate preparation and toxicity test methods.Haring HJ, Smith ME, Lazorchak JM, Crocker PA, Euresti A, Blocksom K, Wratschko MC, Schaub MC.Environ Monit Assess. 2012 Dec;184(12):7343-51. doi: 10.1007/s10661-011-2503-y. Epub 2012 Jan 26.PMID: 22278676
  • 3 Toxicity assessment of sediments from the Grand Calumet River and Indiana Harbor Canal in Northwestern Indiana, USA. Ingersoll CG, MacDonald DD, Brumbaugh WG, Johnson BT, Kemble NE, Kunz JL, May TW, Wang N, Smith JR, Sparks DW, Ireland DS. Arch Environ Contam Toxicol. 2002 Aug;43(2):156-67. doi: 10.1007/s00244-001-0051-0.PMID: 12115041
  • 4. Using a modified dredging elutriate testing approach to evaluate potential aquatic impacts associated with dredging a large freshwater industrial harbor.Watson-Leung T, Graham M, Hartman E, Welsh PG.Integr Environ Assess Manag. 2017 Jan;13(1):155-166. doi: 10.1002/ieam.1790. Epub 2016 Jul 18.PMID: 27144596
  • 5. Environmental fate of pyrethroids in urban and suburban stream sediments and the appropriateness of Hyalella azteca model in determining ecological risk.Palmquist K, Fairbrother A, Salatas J, Guiney PD.Integr Environ Assess Manag. 2011 Jul;7(3):325-35. doi: 10.1002/ieam.162. Epub 2011 Apr 1.PMID: 21120905Review.
  • 6. Sediment toxicity assessment using zebrafish (Danio rerio) as a model system: Historical review, research gaps and trends.Saiki P, Mello-Andrade F, Gomes T, Rocha TL.Sci Total Environ. 2021 Nov 1;793:148633. doi: 10.1016/j.scitotenv.2021.148633. Epub 2021 Jun 22.PMID: 34182436Review.
  • 7. Dr. Houser’s written response to DOI scientist Lynch:Response to Lynch: Summary : Dr. Paul R. HouserAdditional Information as to the mechanism of heavy metals concentrations into lakes:

Heavy Metal Contamination in the Surface Layer of Bottom Sediments in a Flow-Through Lake’ 
Heavy Metal Contamination in the Surface Layer of Bottom Sediments in a Flow-Through Lake: A Case Study of Lake Symsar in Northern Poland



  1. Ken Noble

    William is one of the most intelligent, trustworthy, thoughtful men in Syskiyou County.

  2. James Danaher

    I’m in Santa Cruz county, and not directly affected by the effects of dam removal and sediment release in the Klamath River area. However, I’m disturbed by dirty politics supported by dishonest scientists. This was a great article, and thumbs up to Mr. Simpson for preparing this article, and to the Siskiyou News for publishing this article.

  3. Allen Aronson

    How did all this pollution get there in the first place? Colonizers who exploited the natural resources so carelessly and continue to do so today. The mining industry blasted the mountainside released thousand of tons of wasteful byproduct that leached into the river. The farming industry practices continue to release detrimental pollution into watersheds. This amount of dirty PCBs, DDT, Chromium, Arsenic, Aluminum, Lead, Dioxin, Furan, Copper should never have used in the first place. Natural process needs time to clean up after over 100 years of abusive industry practices before final judgement of succeess or failure.

Leave a Comment

Your email address will not be published. Required fields are marked *