Despite bacteria closure, King County lakes cleaner than ever
Aug 4, 2014, 3:48 PM | Updated: 4:20 pm
Despite the closure of Seattle's Matthews Beach because of bacterial contamination, officials say local waters are safer than ever. (Seattle parks image)
(Seattle parks image)
Seattle’s popular Matthews Beach remains closed to swimming because of high levels of fecal coliform bacteria through at least Tuesday. But as the hot weather continues, experts says there’s no need to worry about widespread water quality problems.
The closure is the first on Lake Washington since 2009, according to Debra Bouchard, water quality planner with the King County Department of Natural Resources and Parks.
The county monitors local lakes and streams annually from May 12 through September, testing water quality every week. If the sampling detects higher levels of fecal coliform bacteria or toxic algae, the water is tested again over the course of several days before a closure is ordered.
“We don’t take beach closures lightly, so we want to make sure that there is a problem before we make any decisions,” Bouchard says.
The cause of the contamination isn’t known. While high levels of fecal coliform bacteria are commonly associated with waterfowl, Bouchard says Matthews Beach is also affected by nearby Thornton Creek, which constantly has high bacteria counts.
“It could be influenced with the warm weather, and there haven’t been any storms to distribute the water that might be flowing out of Thornton Creek, so that’s one suspect,” Bouchard says.
Bouchard says there are so few closures these days because water quality has significantly improved over the past few decades, thanks to greater enforcement of illicit discharges into local waters, and better control of waterfowl at local beaches.
“I know in Juanita Beach they’ve redone the entire beach and dock to allow more water flow so it got better flushing,” she says. “Other jurisdictions are sweeping up goose poop instead of just rinsing it off docks and into the water. So I think there are management strategies that have really helped.”
The biggest cause of concern is creeks near swimming beaches. Along with Thornton Creek, Idylwood Creek flowing into Lake Sammamish and John’s Creek, which flows into Lake Washington near Renton’s Gene Coulon Park, all regularly register high counts of fecal coliform bacteria.
Results of the latest tests on Matthews Beach are expected by Tuesday. The water will be reopened to swimmers Wednesday if levels fall back below unsafe levels.
Check current King County water quality levels here.
