National Marine Sanctuary
Puget Sound’s krill and microscopic plants are contaminated with pollutants from car exhaust and wood stoves. Baby seals are tainted with industrial flame retardants and mercury, which could be shrinking their levels of vitamin A, a safeguard against disease. From plants to mammals, everywhere scientists look in Washington’s inland sea, they discover toxic chemicals. But where does all of this junk come from?
New research from the state Department of Ecology shows that stormwater runoff is sweeping pollutants off the region’s rooftops, roadways, farmlands, and forests and dumping them into streams and rivers that feed the Sound. As much as 800,000 pounds of petroleum pollution and 525 pounds of mercury are sluiced into the sea each year. The toxics settle into mud or are gobbled up by sea life and can move up the food chain to people and orcas.
This summer, Ecology’s data will be pooled with research on plankton, fish and seals that was released in March from the Washington Department of Fish and Wildlife and other agencies. The goal is to create a more complete picture of where the pollution is coming from, what affect it has, and, ultimately, how to clean up the mess.
“This is one of the big challenges of our time, as far as the health of Washington state goes, and the health of Puget Sound,” said Mo McBroom, policy director for Washington Environmental Council, which has lobbied for new funding sources for stormwater cleanup.
The Ecology study marks the first time that researchers have taken direct measurements of pollutants in local waterways to try to calculate the volume of toxic chemicals that is flowing into the Sound via stormwater. Earlier studies largely relied on pollution estimates from other regions.
In the study titled “Toxics in Surface Runoff to Puget Sound: Phase 3 Data and Load Estimates,” the scientists measured the chemicals at 16 sites within the Snohomish and Puyallup river watersheds. The samples were grabbed before and during storm events in order to figure out how much pollution was present under normal or “baseline” conditions compared to the levels when stormwater runoff was added to the mix. The streams were selected to represent four types of land use: forests, agriculture, residential, and commercial/industrial.
For most of the chemicals, the new results show lower amounts of pollution than previous studies — even 100 or 1,000 times lower in some cases. That has prompted some organizations that track the restoration of the Sound to call for a re-evaluation of earlier policy decisions.
“Now we can pinpoint where are the specific areas in Puget Sound that have the biggest problems,” said Brandon Houskeeper, policy analyst with Washington Policy Center, a conservative-leaning think tank. “We should have new policy directives that are very specific.”
Those involved with the new study emphasize that despite the revised numbers, stormwater remains a major challenge to recovering the Sound.
When it comes to pollution sullying Puget Sound, said Rob Duff, manager of Ecology's Environmental Assessment Program, “runoff continues to be the main pathway.”
The water streaming off the Northwest’s towering evergreen forests is pure and clean, right? Wrong. Ecology’s study shows that PCBs, mercury, and other pollutants are flushed with runoff from Washington’s forests. In fact, because forests make up 83 percent of the land surrounding the Sound, most of the pollution reaching the sea comes from that category of land use.
Still, it’s hard to imagine how these chemicals are tainting the woods in the first place. It turns out that industrial air pollution from near and far settles on trees and is washed to the ground. And many of the area’s forests are far from pristine, crisscrossed with logging roads that shed dirt and debris into streams.
Some of the largest volumes of pollutants coming from forestland include the dirt that clouds rivers and can smother fish eggs. Forests are also responsible for roughly 10,000 tons of “oil and grease,” which includes naturally occurring compounds from decaying plants and other sources.
While forests are a sizeable source of pollution, the stormwater runoff that comes from housing tracts, strip malls, and industrial zones is far fouler, and often with much higher concentrations of more poisonous chemicals. Forests shed approximately 10 times the volume of PCBs and flame retardants compared to commercial and industrial sites, but forests cover greater than 100 times more land than business zones do.
Given how much more pollution would be getting into the Puget Sound if more of the land were developed, “it’s a darn good thing that 83 percent of our watershed is forested,” said Mindy Roberts, project manager for the Ecology study.
Uncontrolled sprawl threatens to change that. “As you move urbanization out into these forestlands, you’re going to expect to find that those lands will start to have higher rates of toxics,” Duff said.
That could further imperil struggling salmon runs and other wildlife, plus threaten human health. Water samples taken from business and industrial zones were contaminated with lead, copper, PCBs, DDT, and cancer-causing chemicals called polycyclic aromatic hydrocarbons (PAHs) at levels that exceed safety standards set either for humans or the environment. Runoff from the region’s residential areas was soiled by phthalates — an industrial chemical added to countless consumer goods to make plastics softer and beauty products smell better — at concentrations that violated human health standards.
Those concerned about the toxic chemicals say we need to find a solution.
“We have to figure out a better way to control the flow of these chemicals,” said McBroom. “That points us toward low-impact development.”
Low-impact development is a strategy for controlling stormwater runoff. It calls for the preservation of native plants and trees that can slow the flow of rainwater and clean up pollution. It uses engineering tools such as rain gardens, green roofs, and porous asphalt to help the runoff soak into the ground instead of gushing untreated into streams and lakes.
Low-impact development can be used when building in previously undeveloped areas, or existing homes, businesses, and roadways can be “retrofit” with the technologies to reduce stormwater damage. Considering the higher concentrations of toxics coming from these already-built areas, one of the report’s conclusions is that there could be a significant pay off if some of these areas are targeted for retrofits.
Steps already are being taken to expand the use of low-impact development. Ecology currently is accepting comments on a draft proposal for more stringent requirements for the use of low-impact development in the region, and this spring Washington State University and Stewardship Partners launched an initiative to build 12,000 rain gardens around Puget Sound over the next five years.
When it comes to cleaning up stormwater, McBroom said, “it’s fundamentally an infrastructure problem.”
While low-impact development is seen as an essential tool for fixing the region’s stormwater mess, a complementary strategy is keeping the pollutants out of the environment in the first place. And when it comes to curbing copper pollution, Washington has been a national leader.
Ecology’s study shows that the amount of copper swept into the Puget Sound each year is around 79,000 pounds. That’s the weight of nearly 36 million pennies. While people can safely hold a penny or drink water from a copper pipe, the metal means trouble for fish, say scientists with the Northwest Fisheries Science Center. When salmon and other species are exposed to minute amounts of copper in the water it deadens their sense of smell, which means they have a hard time finding food and their spawning streams and avoiding predators.
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