Geology topics

Byron Neil Aldridge

Publications and source records attributed to Byron Neil Aldridge.

2 recordsLinked to original sources

USGS1984

Floods of October 1977 in southern Arizona and March 1978 in central Arizona

Major floods occurred in October 1977 and March 1978 in Arizona. As much as 14 inches of rain fell during October 6-9, 1977, over the mountains of southern Arizona and northern Mexico resulting in the highest discharge since at least 1892 on the Santa Cruz River upstream from Tucson. The flood inundated areas as much as 4 miles wide, covered at least 16,000 acres of farmland, and caused $15.2 million in damage. Residential losses occurred at Nogales, Amado, Green Valley, and Sahuarita. Severe erosional damage occurred along the Santa Cruz River, Agua Fria Canyon, Potrero Creek, and many small drainages in the Sonoita Creek basin. The peak discharge in Agua Fria Canyon was the highest since before 1900. Less severe flooding occurred along the San Pedro River and the Gila River downstream from the San Pedro. Widespread rainfall of 3 to 6 inches and 9 to 14 inches in some areas in the central mountains during February 27 to March 3, 1978, caused the highest discharge since 1920 on the Salt River in Phoenix and resulted in three deaths. Flooding along the Salt and Gila Rivers and several lesser streams caused statewide damage totaling $65.9 million, of which about $37 million occurred in Maricopa County. Nine counties were declared disaster areas. During the flood of March 1978, moderate peak discharges and unusually high volumes of runoff occurred on tributaries to the Salt and Verde Rivers upstream from a system of reservoirs. Flood magnitudes were greater at the main-stem gaging stations than on the tributaries. The peak discharge into Theodore Roosevelt Lake, which was 21 percent full at the start of the flood, was about 155,000 cubic feet per second, the largest known from 1890 to 1978. The reservoirs stored large quantities of water and greatly reduced the magnitude of the flood. The peak discharge of the Salt River was 125,000 cubic feet per second below Granite Reef Dam and 122,000 cubic feet per second at Phoenix. Discharges in excess of 100,000 cubic feet per second occurred for 8 hours. Without the storage provided by the reservoirs, the peak discharge on the Salt River would have been 260,000 cubic feet per second, and the discharge would have exceeded 100,000 cubic feet per second for 66 hours. The Verde River was the principal flood source, but flows at the upstream gaging stations did not indicate the magnitude of the impending flood at Horseshoe Reservoir because large inflow from tributaries immediately upstream from the reservoir caused the river to rise at downstream stations before it rose at upstream stations. About 17 percent of the water entering the reach from Granite Reef Dam to Gillespie Dam went to recharge, temporary ground-water storage, or evapotranspiration losses. All water was stored at Painted Rock Reservoir and released at a low rate that prevented water from reaching the Gila River near Mohawk gaging station.

Water Supply Paper↗

USGS1984

Floods of November 1978 to March 1979 in Arizona and west-central New Mexico

Severe flooding occurred in parts of the Little Colorado and Gila River basins as a result of a storm that occurred December 17-20, 1978. The central highlands received 3 to 10 inches of precipitation that was augmented by snowmelt to altitudes of 10,000 feet. The storm was preceded by extremely large amounts of rainfall and runoff in November and was followed by other periods of high runoff in January and March 1979. In some areas flood peaks in November, January, or March were higher than the peak of December 1978. At Winslow, the discharge of the Little Colorado River in December 1978 was the highest since at least 1952. The discharge of the Gila River above the San Francisco River was probably the highest since at least 1891, and in the Safford Valley, the peak was the highest since 1916. The Agua Fria River below Waddell Dam had the highest discharge since 1919. The flood of December 1978 caused 12 deaths and caused damage that was probably in excess of $150 million in Arizona and west-central New Mexico. Damage was estimated to be $51.8 million in Maricopa County, Arizona. Floods caused extensive agricultural damage along the Gila River in Virden Valley in New Mexico and in Duncan, York, and Safford Valleys in Arizona. Duncan, Arizona, was flooded with as much as 7 feet of water. The flood crest on the Gila River in December 1978 moved from Redrock, New Mexico, to Duncan, Arizona, in about 6 hours, which is more rapid than during other recent floods but is comparable to the travel-time recorded in 1941. Travel-time in the reach varies with discharge and is about 14 hours for discharges of 10,000 cubic feet per second and 5 hours for discharges of more than 40,000 cubic feet per second. Water-conservation reservoirs on the Gila, Salt, Verde, and Agua Fria Rivers and a flood-control reservoir on the Gila River had a major influence on the magnitude of floods downstream from the reservoirs. All runoff from the Gila River basin upstream from Coolidge Dam, Arizona, during the floods of November 1978 to January 1979 was stored in San Carlos Reservoir, and major flooding was averted along the Gila River between Coolidge Dam and Salt River. Minor flooding occurred along the Gila River downstream from San Pedro River. Floods in central and western Maricopa Count, Arizona, were caused by the release of water from full reservoirs on the Salt, Verde, and Agua Fria Rivers, but peak discharges and duration of the floods were much less than would have occurred if the reservoirs had not been in place. Flow continued in the Salt River through Phoenix until May 1979. Floodwater was stored in the flood-control reservoir above Painted Rock Dam on the Gila River in order to prevent major damage along the Gila and Colorado Rivers. Water was released from Painted Rock Dam until January 1980. The prolonged flows and reduction in ground-water pumping caused ground-water levels to rise appreciably in many areas.

Water Supply Paper↗