Never fails. I'm running late, and I get stuck behind these street washers. As you can tell, I took this shot from my car while waiting to go down the street. The water that is used is drinking water. I always thought this was a waste of good water, but the alternative is either not washing down the streets (here they were washing away to somewhere a lot of leaves blown down in a storm the preceding night) or else washing the streets with river water. That water, unfortunately, is often polluted with waste of all kinds....the Danube is more brown than blue here, due to poor enforcement of dumping laws.
Sometimes if you beep at these fellows and point to your windshield, they will happily hose your car down! Gets it quite clean, but make sure your windows are up first...