Ever see a dried out stream or brook that sometimes, after a good rain, is racing with water? That's an arroyo, or a creek that dries out and fills with water depending on the time of year and weather.
The Arroyo Seco in Southern California is an example of a well-known arroyo. Its name, which translates from Spanish to mean "dry stream" is an apt way to describe what an arroyo is — dry at times, and flowing at others. An arroyo can be natural or man-made. The Los Angeles River, for example, is an arroyo that runs along a concrete channel and helps distribute fresh water to the city.