Do you know what a hydrant is? It's like a pipe on the street that firefighters use to get water to put out fires. Well, a flushing hydrant is a special kind of hydrant that's used to clean and test the pipes that bring water to your home and other buildings.
You see, over time, dirt, rust, and other icky stuff can build up inside these pipes and make the water dirty or taste funny. That's not good! So, to make sure the water stays clean and safe, the city workers will open up the flushing hydrant and let water rush through the pipes at a really fast speed. This high-pressure water will blast away any dirt or sediment that's stuck inside the pipes, kind of like how you wash your hands with soap to get them clean.
Sometimes, when workers are flushing hydrants, you might see a lot of water shooting out of the hydrant and spilling onto the street. Don't worry, they're not wasting water! They're actually doing it on purpose, to make sure the water is flowing smoothly and the hydrant is working properly.
So, if you ever see a flushing hydrant in your neighborhood, remember that the workers are doing an important job to keep your water clean and safe.