I’m not sure if this is the case everywhere but where I am at the storm sewers empty water from the streets into the lakes and rivers that eventually go to the ocean. I’d really like to see us disconnect those sewers from the rivers, lakes, and oceans to keep that crap out of the water.
Edit: clarify language a bit.
Sheldon Browns website is an encyclopedia of bicycle knowledge. Especially for older stuff. RIP. https://www.sheldonbrown.com/