Roads and parking lots don't look like streams, but they are. Princeton Shopping Center is one of the "headwaters" of Harry's Brook, and its snowmelt offers a good demonstration of how water flows from pavement to stormwater pipe to the brook itself. The subtle sheddings of brakepads, tires, and leaky engines, along with the not so subtle salt residue and litter, are hastened by the rain to join whatever aquatic life resides downstream. Washing all of this "away", a rain seems cleansing to us, as it sullies an unseen nature that's expected to quietly absorb the recurrent insult and carry on.
There's a similar deception at work in the chimneys of our homes. If the environment gains hardly a mention in the political world, it's because pollution is now largely unintentional, hidden, diffuse, subtle in its source and distant in its impact.