PORT TOWNSEND — A study of bacterial pollution in the Chimacum and Ludlow creek basins found good news and bad news.
Though there was a fairly significant improvement in Chimacum Creek, half of the monitoring stations are still failing the state standard, said environmental health specialist Anna Bachmann with Jefferson County Public Health, which conducted the study with the Jefferson County Conservation District.
“There were some improvements in some areas and declines in others,” she said.
The state Department of Ecology funded the project, which included two years of bacteria sampling in the creeks and one year of shoreline sampling along about 7 miles of the Ludlow Bay shoreline from south of Mats Mats Bay to Tala Point.
The project also had an extensive educational component that involved conducting door-to-door sanitary surveys of properties with on-site septic systems in the Chimacum and Ludlow basins.
Bachmann said the goal of the project was to look for bacteria and identify public health concerns.
The presence of bacteria in the water can mean other pollutants are there, too.
“The reason we do these projects is we are protecting recreational beaches,” Bachmann said. “We don’t want people swimming where there is sewage or bacteria.”
Another goal is protecting shellfish.
“It’s a public health concern for people eating shellfish that might be impacted by bacteria,” she said.
The last time monitoring was done for bacteria in Chimacum Creek was in 2011-12. Of the 28 stations that were sampled at that time, 86 percent and 82 percent of the sample stations were failing the state standard in the wet and the dry seasons respectively. But in 2015-16, the failure rate had dropped to 48 percent during the wet season and 68 percent during the dry season.
By comparison, Ludlow Creek is in much better shape than Chimacum in terms of water quality. Just over half the size of the Chimacum Creek Basin, the Upper Ludlow Basin has comparatively more forest lands and less agricultural and pasture lands than the Chimacum Basin, Bachmann said.
All of the 20 stations that were sampled monthly, all stations on Ludlow Creek’s main stem and main tributaries, passed the state standard. Only one station, on Inner Harbor West Creek, failed the standard in both the wet and dry seasons.
The sources of bacteria with the watershed include livestock, humans, pets and wildlife, Bachmann said.
In Chimacum, many miles of fencing have been installed along the creek and its tributaries since the 1980s. As a result, fecal coliform levels downstream of agricultural areas have decreased substantially.
DNA analysis on water samples collecting in 2011-12 shows that human sources were identified five times more frequently than ruminant sources, which include cattle livestock and wildlife.
There are more than 2,300 septic systems in the Chimacum watershed and more than 300 in the Ludlow watershed. Part of the project was focused on evaluating those systems.
The tests show that there is still plenty of work to be done in Chimacum Creek. The lower part of the creek is on the state Department of Ecology’s 303(d) list of impaired waters.
“There’s a lot more work to be done because we haven’t yet cracked the nut,” Bachmann said.
A source of the problems on Chimacum Creek is the high density of septic systems, she said, adding that a long-term solution could be putting in a sewage system.
“That may be the ultimate solution for getting Chimacum Creek off the 303(d) list,” she said.
For now officials will focus on collecting data at other areas throughout the county, but will return to the Chimacum and Ludlow areas. Funding can be difficult for the project, she said, adding that the county relies on Ecology grants.
“I feel we have barely scratched the surface and we will probably be back,” she said.
Reporter Jesse Major can be reached at 360-452-2345, ext. 56250, or at [email protected].