Jonathan White is a member of the San Juan County Marine Resources Committee and chair of the Northwest Straits Commission.

Joe Gaydos is the director of SeaDoc Society, a member of the Puget Sound Partnership science team, and a governor-appointed member of the Northwest Straits Commission.

While driving home from a recent storm water workshop, a friend asked, “Is run-off from my small property really making its way to the ocean and causing damage? My family has lived here 20 years, and we care about the environment as much as anyone. Why is this suddenly becoming a problem?”

It’s a good question. When we look to science for the answer, we find that it isn’t always exact enough to show specific effects from specific human behaviors.

While science may not be able to tell us the specific effect of each and every household, it does tell us something unequivocally: that polluted run-off is making its way into our environment in quantities that are measurable and damaging.

Mike Kaill of San Juan Island maintains a public aquarium at the end of Spring Street where he cares for anemones, fish and other marine creatures. The aquarium circulates seawater from the harbor. Several years ago, Mike noticed that some of the critters were dying, so he tested the water. What showed up surprised him. In repeated tests over the last three years, surfactants and other compounds were showing up in lethal doses. Lethal to local marine animals, that is.

Where are these contaminants coming from? They come from fertilizers we put on our grass, detergents we use to wash our dishes and cars and clothes, pharmaceuticals we flush down the toilet, and fluids that leak from our car. All this and more shows up in the wild fish that swim our waters, bite our lures, and end up on our dinner plates. A scientific report commissioned by the Puget Sound Partnership estimates that 150,000 pounds of toxins from polluted runoff spill into Puget Sound each day.

It’s hard to get our mind around 150,000 pounds of toxins a day, particularly when we live in a rural county with a relatively small population. As our friend’s question indicates, it’s especially hard to envision this problem when our individual habits don’t appear to be a significant and traceable part of the problem. This is where science isn’t much help. Science, for example, can’t add color to the detergent I used last weekend to wash my car and follow it down the storm drain – like a stick floating downstream — until it shows up in Mike’s aquarium. But, if we colored the detergent of a hundred neighbors who washed their cars over the last year, the color may very likely show up in the bay. This is what scientists call cumulative effects (some of us know it better as “death by a thousand cuts”). The detergent I used last weekend didn’t kill Mike’s fish, but when you add the habits of many neighbors over many years, it did.

Science is a valuable part of the picture, and we need to keep it up to better understand the many-layered and exquisitely complex elements of our world. But, honestly, how much do we need science to explain before we acknowledge that some of our habits are causing damage?