Sad news, but having the diagnosis is a good step towards realizing a cure, at least. More public transit (investment) moves the same number of people on fewer tires and less road area, for one thing.

This seems like an important problem. We need to avoid falling prey to the tactics used by tobacco & oil. Humanity does have an important role to play in the ecosystem: not as exploiters, but as stewards.

We need more stormwater filtration. Rain gardens are great. So is permeable concrete. So is reducing traffic but I think filtration can spread before traffic is measurably reduced.

A good article in The Stranger. Well I guess at least one a year is a must. I liked that you avoided the term bioswale even.

Kind of surprises me this is presented as news. I personally collected runoff samples from a station on I-5 near 145th as part of a roadway runoff study---in 1980. The impact of roadway runoff on the environment, whether it be lead, asbestos, hydrocarbons or other has been well documented.

and
then
there's
Plastics:

we Banned thin plastic grocery bags
only to have 'em be Replaced
by Heavy Duty plastic bags.

somebuddy's
Fucking
with
Us

why do
they HATE
Life on Earth?

Obviously building nationwide high speed rail with a statewide bike path network designed for e-bikes will fix 90 percent of this, along with proper roadside design to keep the tire dust from the existing vehicle traffic out of the streams.

But ... it's really the increased temperatures of the streams, caused by forest diseases and fires that have cut the shade protection for the streams and their water sources.

@6 KEK55, @7 kristofarian, and @8 Will in Seattle: +3 Agreed. Your statements are well said. A lot will have to change if we are to fully save our dwindling salmon populations, preserve our forests, keep our air breathable, and our water supplies safely potable. There is no one easy fix-all answer. I never would have guessed tire dust in stormwater, but it makes sense. I guess It's a good thing that by only driving seasonally my beloved VW and I are helping to save salmon, and the rest of us who live on it.

So we need to invest a bunch of money into cleaning up a problem created by tire manufacturers, even though subsititutes have been identified, so they can make more money poisoning our environment?
If we tax users of the products (drivers) for tires containing the poison there will quickly be a solution (and naturally a lot of complaining).
Or we can tax everyone fairly (which Washington state is so good at) and make sure business continues as usual.
Give them one year to replace the chemical, then tax the shit out of those that don't comply.