Tag Archives: 3-303 interchange

Mosquitos and the 3-303 detention pond

The in basket: Back last August, Megan McCumsey ended an e-mail with an unfavorable comment on the design of the controversial SR3-303 interchange in Silverdale by saying, “But what I wonder is, why, oh, why did they make that huge lake that must just breed mosquitos?

“It isn’t a wetland. It’s a big stagnant lake. Or am I all wet?”

The out basket: It’s a detention pond for groundwater, of which there is a lot running underground from the hill to the west in addition to whatever flows into it on the surface.

You’ll find that most state highway projects these days will include the addition or expansion of such a detention pond, a major added cost factor in modern road building. Most aren’t as obvious or constantly full as that one, though.

I have written about it before, when I was told that while it’s impressively large in area, it’s extremely shallow. Still, it never dries up, not even in the summer when mosquitos are a worry.

I asked the state if they take measures to control mosquitoes.

The state’s response is couched entirely in terms of the West Nile Virus, a more serious concern than simple annoying skeeter bites. It even has a Web site discussing it at length. It doesn’t specifically address the Silverdale pond, though.

The site says, among other things, “WSDOT employees are trained to test, or dip, possible roadside breeding areas such as ponds and ditches for mosquito larvae. WSDOT has implemented Department of Ecology’s ‘Best Management Practices for Mosquito Control’ as our integrated pest management plan, using natural bacterium called Bacillus thuringiensis israelensis (Bti) and Bacillus sphaericus to control mosquito larvae, if found. The products we use are applied in the form of pellets or briquettes and are natural larvicides that do not harm fish or animals.”
Duke Stryker, head of state highway maintenance in this area, said he does have staff trained in the sampling and testing, but it is not a high priority. There was a treatment of the Silverdale pond some years ago, he said.

“It’s not on a schedule to be tested,” he said. “As our program evolves, testing has become a lesser priority, because we have not had an issue with West Nile.”