One needn’t be a card-carrying environmentalist to know that it’s a bad thing for salmon to go belly up before spawning their eggs. But that’s just what’s happening to many fish returning to some of the urban streams in Puget Sound.

Toxic chemicals are flushed with rainwater runoff from city roads, parking lots and rooftops directly into streams and creeks. The chemicals are poisoning coho salmon that return to have babies. Multiple local salmon runs are at risk of extinction.

And as Seattle continues its epic building boom, there’s a risk that things could get worse for fish and other native creatures as the number of roofs, cars and people increase.

Read more at Geekwire