South Kitsap’s Karcher Creek earned an unwanted distinction this week, having been added to the Kitsap Health District’s watch list because of high bacteria contamination levels.
Five other streams in the county were already on the list, including Bear Creek, also in South Kitsap.
The announcement about Karcher Creek came as the Health Department released its 2010 Water Quality Monitoring Report, summarizing bacterial contamination levels in Kitsap County lakes, streams and marine waters.
“We can’t put our finger on exactly what’s causing the problem,” Shawn Ultican, environmental health specialist with the Health Department’s Water Quality Program. “Our samples only measure the level of contamination, not the source.”
Ultican said fecal coliform bacteria originate in the feces of any warm-blooded mammal.
“That means the contamination could be coming from failing septic systems,” he said, “or it could be manure from farm animals or even from the native wildlife.”
Another possibility, Ultican said, could be a leak from sewer pipes.
“We ran a smoke test a few years ago with the West Sound Utility District and didn’t find any problems there, either,” he said. “But it’s possible something went bad in the years since. We want to eliminate all the possibilities.”
The next step, Ultican said, is to take more samples from a wider range of locations within the stream to pin down the hot spot.
“Most of the homes adjacent to the stream are on the sewer system, but a few still have septic tanks,” he said. “We’ve already checked a lot of the houses and haven’t found a problem yet.”
The agency began posting warning signs on local streams known to be chronically and severely contaminated with fecal coliform (FC) bacteria in 2005.
High FC levels indicate the presence of viruses and other pathogens that can make people sick.
According to the Health Department’s standards, a contaminated stream is defined as having FC bacteria contamination concentrations with a geometric mean value of at least 270 parts per 100 milliliters, including data from samples collected between May and September of the previous three years.
Karcher Creek’s FC level for 2010 was calculated to be 297.
By contrast, Bear Creek scored a 422 and the county’s most contaminated stream, Lofall Creek, was at 654.
According to the Health Department Report, “The number of streams with public health advisories has been increasing over the last few years but is still lower than the peak in 2007.”
That year, the Health Department had 11 streams on its watch list; in 20009, there were only two.
Karcher Creek, located just east of the Port Orchard city limits, is comprised of around two miles of streams and tributaries.
The stream discharges into the southern shoreline of Sinclair Inlet near the Karcher Creek Sewage Treatment Plant.
“(Karcher Creek) water quality is still very poor,” the Health Department report notes, “and the creek has a stationary overall trend.”
Bear Creek, South Kitsap’s other steam included on the current watch list, is a tributary of Burley Creek, which has been a source of concern for several years.
“We’ve been working for several years to try and pin down the source of the contamination in that area,” Ultican said. “Sometimes it’s one specific thing, like a home with a major septic system leak, and you can cledar it up pretty quickly. Other times, it can take years. You just never know.”
