The Rio Salado at flood
— Alison C. Simcox

The Rio Salado watershed, 24 km north of Socorro, has a drainage area of 3570 km². It is bounded on the north by the Ladron Mountains and the Colorado Plateau and on the south by the Datil, Gallinas, Bear, and Lemitar Mountains. Alamocito Creek flows eastward from the northern slope of the Datil Mountains for 48 km at an average gradient of 18.6 m/km before joining with Gallegos Creek to form the main stem of the Rio Salado. From this confluence the Rio Salado flows eastward for about 72 km at an average gradient of 6.2 m/km to join the Rio Grande near San Acacia.

Annual precipitation ranges from an average of 430 mm in the mountainous areas to 180 mm in lower elevations. A large percentage of rainfall occurs as late summer thunderstorms which produce rapid run- off, flash flooding and severe erosion. The Rio Salado and the Rio Puerco to the north contribute about 75 percent of the sediment to the Rio Grande at San Acacia, although their flows are less than 10 percent of the Rio Grande volume at that point (U.S. Corps of Engineers, 1973). The detrimental effects of sediment-laden water on crops and on the Elephant Butte Reservoir, and fear of another 1929-sized flood, which devastated the middle Rio Grande valley, makes the Rio Salado one of the major targets of flood- and sediment-control schemes. This paper compares channel characteristics and discharge measure- ments made during 1982's peak discharge to those estimated from high- water marks a few days after the flood.