arroyo
ah-ROY-oh
A dry creek bed or gulch in the desert that carries water only during and immediately after rain — a channel carved by flash floods and bone-dry the rest of the year. Arroyos are the drainage architecture of arid landscapes, cutting deep into alluvium and soft rock, their steep banks revealing soil layers and fossil roots. They are also traps: a clear sky overhead means nothing if it's raining in the watershed above. An arroyo can go from dusty trail to roaring, debris-laden torrent in minutes.
Etymology
Spanish, from Latin arrugia, a gold mine shaft or water channel. The word came to the New World with Spanish colonists and is the standard term across the American Southwest.
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