Santa River

The Santa River, located in the Andes mountain range of Peru's Ancash Region, originates from Lake Conococha at an altitude of 4,050 meters above sea level. The lake is fed by streams from the Cordillera Negra to the west and the Cordillera Blanca to the east, with its main tributary being the Tuco River, which flows from Lake Tuco at approximately 5,000 meters elevation. The Santa River flows north for 200 kilometers between these mountain ranges, forming the fertile Callejón de Huaylas valley. It then turns west and passes through the narrow Cañon del Pato gorge before reaching the coastal region.

During the dry season (June to November), water availability is limited, necessitating reservoirs to manage fluctuations. The river's watershed covers 4,900 square kilometers upstream of the Huallanca hydroelectric power plant and 7,300 square kilometers downstream. After a total course of 347 kilometers, the Santa River empties near the town of Santa, close to Chimbote on the coast. In 1984, gold dust was discovered at its mouth, sparking regional interest.

Towns along the river include Conococha, Recuay, Huaraz, Carhuaz, Yungay, Caraz, Huallanca, Yuracmarca, and Santa. The region is prone to natural disasters, with historical events such as a 1941 flood destroying part of Huaraz and killing thousands, and avalanches in 1962 and 1970 causing further devastation. These events are often triggered by glacial movements leading to sudden water releases and landslides.