Researchers believe at least 14 to 94 million pounds of contaminants like oil, grease and toxic metals get mixed with storm water in Puget Sound, a sound of the Pacific Northwest, every year.
To mitigate the issue, nonprofits such as the Nature Conservancy are working with local companies like Stephen C. Grey & Associates and Boeing, according to KOMO News. The runoff from the Aurora Bridge is the target for a new project.
The Washington State Legislature approved $500,00 to help with the project.
With the proposed system, water spills from the bridge and Cascades through a garden. Then, soil, rocks and vegetation capture as much dirt and pollution as possible before the water reaches Lake Union, reported KOMO News.
This project will occur in three phases and will filter about 2.3 million gallons of storm water annually.
"I think, you know, particularly with climate change upon us, we’re going to see an increased amount of rain flow here in the Puget Sound, and as our population grows, the amount of storm water is only going to increase," said Chris Hilton, the Nature Conservancy's urban partnership director.
The Puget Soundkeeper Alliance will also see this Aurora Bridge project underway, underscoring the importance of remedying the problem of polluted stormwater.
Currently, the Puget Soundkeeper Alliance is working on a project that encourages Puget Sound cities to make sure they're making requirements for low-impact development like those being built under the Aurora Bridge.
The state has allotted a million dollars to launch a similar project at the base of the I-5 ship canal bridge as well, reported KOMO News.