Lake Conococha, at an altitude of 4,050 m
above sea level and at , is considered the headwaters of the Santa River. Lake Conococha itself is fed by small streams from the
Cordillera Negra in the west and the snowcapped
Cordillera Blanca in the east. The main tributary of the lake is Tuco River which has its source at Lake Tuco () about 5,000 m above
sea level at one of the
glacier tongues of mount
Tuco. The Santa River emerges from Lake Conococha and runs for 200 km in a northerly direction between the Cordillera Negra in the west and the Cordillera Blanca in the east, forming the fertile
Callejón de Huaylas. At 2000 m above sea level, the river changes its course to a westerly direction, squeezing through the narrow gorge of
Cañon del Pato ("duck's canyon") before it finally breaks through the coastal ridges. During the dry season from June to November, the Santa River provides only a little water for irrigation, drinking water and hydroelectric power. A couple of water reservoirs have been established to control the fluctuation of the river. Upstream of the hydroelectric power plant at Huallanca, the Santa River watershed covers an area of 4,900 km2, downstream another 7,300 km2. The mouth of the river, after the river runs a total length of 347 km, is at near Santa, 10 km north of the coastal town of
Chimbote. In 1984,
gold dust was discovered in the mouth of Santa River which caused a regional
gold fever among the rural population. ==Towns==