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Bacteria-sniffing canines help track sources of contamination in Kirkland’s Juanita Creek and Seattle’s Thornton Creek


The City of Kirkland Public Works Department and King County Department of Natural Resources and Parks are trying to solve a mystery of sorts and have “called in the dogs” to help.


The City of Kirkland Public Works Department and King County Department of Natural Resources and Parkscanine_bacteria_for_web are  trying to solve a mystery of sorts and have “called in the dogs” to help.

The State of Washington has identified Kirkland’s Juanita Creek and Seattle’s Thornton Creek as having bacterial contamination and to seek out the sources, canine tracking dogs will be sniffing for clues.

Two dogs from Environmental Canine Services, Inc., Molly, a Border collie, and Crush, an Australian cattle dog, will use their scent tracking skills to help pinpoint sources of human sewage in the creeks.  

"Nearly 60 years after Jim Ellis started efforts to clean up Lake Washington, it is unacceptable that these problems still exist,” said King County Councilmember Rod Dembowski. “We welcome Molly and Crush to the team and we look forward to finishing the job of improving water quality and minimizing exposure to pathogenic disease, particularly where there are nearby swimming beaches.”

Sources of human fecal contamination in Juanita Creek could be due to leaking septic tanks or improper connection of sanitary sewers systems to the creek. Other sources of contamination could be from animals, such as raccoons, geese or beavers. Molly and Crush will either bark or sit down to indicate that they have detected human bacteria in a sample. Their handlers will note the results, which will help to focus the search for the source of the pollution.

“Canine source tracking is simple and effective way for Kirkland to clean up Juanita Creek,” said Kirkland Mayor Amy Walen.  “Dogs have amazingly sensitive noses and with their help we can find and remove sources of bacterial contamination and avoid closures of the Juanita Beach swimming area.”

Based upon results from May 12 sampling, employee teams will walk sections of Juanita Creek with the dogs on May 13 to further narrow the sources of pollution. Samples will be taken at each location and analyzed by the King County Environmental Laboratory using a variety of tools to identify sewage. Those results will be compared to the canine results to verify contamination identified by the dogs.

The lab will analyze water samples using the conventional techniques to pinpoint fecal coliform bacteria and E. coli bacteria, a select group of organic chemicals found in wastewater. They will also use a new human fecal source tracing method that measures gene copies of host specific genetic markers.  Results from the fecal coliform and E. coli tests will be available within 48 hours. The other results will take a few weeks to process.  

The lab will also analyze water quality results from Seattle’s Thornton Creek, where Molly and Crush will sniff for similar information later in the week.  King County is working with Seattle Public Utilities on that canine detection study.

To learn more about Kirkland’s Water Quality Program, call 425-587-3800 or visit and search “Surface Water.” Learn how the King County Environmental Lab supports regional quality by visiting