Human waste is somehow getting into a North Seattle creek.
Test results released from a recent study have shown high counts of bacteria in parts of Thornton Creek. The report says samples indicate it is highly likely the bacteria is coming from humans.
"You're dealing with something either coming in from the leaking sewer system, the drainage system or potential illegal RV dumping into the storm drains," Stormwater scientist, and author of the study, Jonathan Frodge tells KING 5.
Inspectors are trying to determine the source of the bacteria. They say they'll look for cracks or breaks in the sewer system.
Health officials are recommending the public to stay away from Thornton Creek warning of potential human health risk due to the potential of high levels of bacteria exposure at beaches.
Thornton Creek runs 15 miles, through over 700 backyards, 15 parks and natural areas to Lake Washington.
The Department of Public Utilities says of all the creeks tested in King County, Thornton Creek consistently ranks among the highest for fecal coliform bacteria counts.