Matanza River

The Matanza River is a 64-kilometre (40 mi) watercourse in Argentina that originates in Buenos Aires Province and defines the southern boundary of the Buenos Aires federal district. It empties into the Río de la Plata between Tandanor and Dock Sud. The La Boca neighbourhood and the Boca Juniors football club are located near its mouth. (The Spanish word boca means "mouth".) The river is highly polluted. Its course has been canalized and channelized in places, especially along its lower course. From its source down to La Noria Bridge on Avenida General Paz, the river is usually referred to as Río La Matanza, and from that point onwards as Riachuelo. Approximately 3.5 million people live in its drainage basin of 2,240 km2 (865 sq mi). The south-easterly storm wind, known as Sudestada, hinders the waters of the Riachuelo from reaching the Río de la Plata, producing frequent flooding in low-lying areas like La Boca and Barracas. Since 1995 a number of flood control projects have been carried out to prevent such occurrences. The Matanza's main tributaries are the Cañuelas, Chacón, and Morales streams in the province of Buenos Aires, and the Cildáñez stream (currently piped) in the Greater Buenos Aires urban area.