Quebrada Arroyo Sencata is a high-altitude stream located in the Tarapacá Region of Chile, flowing through one of the most remote and dramatic landscapes in South America. The stream originates in the altiplano and initially flows eastward before turning southward, running nearly parallel to the international border until it empties into the Río Todos Santos just before that river crosses into Bolivia. As the principal tributary of the Río Todos Santos, the Arroyo Sencata drains a watershed of approximately 350 km², entirely within an endorheic basin that forms part of the greater Titicaca-Desaguadero-Poopó-Salar de Coipasa system. The stream's elevation ranges from a minimum of around 4,103 meters above sea level to a maximum of 5,616 meters, with a mean elevation of approximately 4,550 meters — placing it firmly in the puna and high-altitude wetland zone characteristic of this part of northern Chile. The geography is stark and expansive, defined by volcanic peaks, open grasslands, and the thin, clear air of the Andean altiplano.