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B. N. Aldridge

Publications and source records attributed to B. N. Aldridge.

9 recordsLinked to original sources

Effects of vegetation on floods at four Arizona sites

Four examples show the effect of vegetation on stage, discharge or frequency of floods. An 8-year growth of trees on the streambed at site 1 increased channel roughness enough to cause the average water surface elevations that were computed for 10-year and 100-year floods to be 0.49 and 0.91 meters higher than those for a channel without vegetation. A 6-year growth of vegetation and sediment deposition formed 1.5-meter high flood terraces at site 2 and narrowed the channel from 55 meters to about 12 meters. Similar terrace development in 18 years narrowed the channel at site 3 from 139 meters to an average width of 24 meters. At a stage where the channel carried 716 cubic meters per second in 1952, it carried 227 cubic meters per second in 1970. Additional aspects of the subject are discussed.

Conference Paper

STREAMFLOW LOSSES IN THE SANTA CRUZ RIVER, ARIZONA.

The discharge and volume of flow in a peak decrease as the peak moves through an 89-mile (143 km) reach of the Santa Cruz River. An average of three peaks per year flow the length of the reach. Of 17,500 acre-ft (21,600 dam**3) that entered the upstream end of the reach, 2300 acre-ft (2,840 dam**3), 13 percent of the inflow, left the reach as streamflow. The remainder was lost through infiltration. Losses in a reach of channel were estimated by relating losses to the discharge at the upstream end of the reach. Tributary inflow was estimated through the use of synthesized duration curves. Streamflow losses along mountain fronts were estimated through the use of an electric analog model and by relating losses shown by the model to the median altitude of the contributing area.

Conference Paper

Floods of September 1970 in Arizona, Utah, Colorado, and New Mexico

During September 5-7, 1970, unusually large floods occurred in the mountains of central Arizona and in the Four Corners area of Arizona, Utah, Colorado, and New Mexico. Flooding also occurred in southern and northeastern Arizona. The record-high rainfall of September 5 occurred when a mass of moist tropical air from Pacific storm Norma collided with a cold front from the northwest. A new 24-hour precipitation record of 11.40 inches (290 millimeters) was established for Arizona, and new 12- and 24-hour precipitation records of 6.0 inches (152 millimeters) were established for Utah. The flood took the lives of 23 persons and was reported to have caused about $8.4 million in damage in Arizona. The main area of flooding was in the mountains in central Arizona. The flood generally was less destructive with increasing distance downstream; in the Salt and Verde River basins the reservoirs were capable of storing all the floodwater. Flooding in the Dolores and San Juan River basins in the Four Corners area was mostly in rural areas, and two people were drowned in McElmo Creek in Utah. The flood was not as large as that of October 1911, which is the largest known flood in the area. A second storm occurred in the Four Corners area September 12-14; however, the amount of flooding generally was less than that from the previous storm. Flood damage as a result of the two storms was reported to be about $2.9 million.

Arizona, Colorado, New Mexico, Utah

Effects of the catastrophic flood of December 1966, north rim area, eastern Grand Canyon, Arizona

Precipitation from the unusual storm of December 1966 was concentrated on highlands in northern Arizona, southwestern Utah , southern Nevada, and south-central California and caused widely scattered major floods in the four States. In Arizona the largest amount of precipitation was in the north rim area of eastern Grand Canyon, where about 14 inches was measured. The largest flows occurred along Bright Angel Creek and the MilK Creek-Dragon Creek part of the Crystal Creek drainage basin. The maximum effects of the flood were along Milk Creek-Dragon Creek, where a mudflow caused extensive channel modification. Floods that occurred in the Bright Angel and Crystal Creek basins have a recurrence interval of only once in several centuries. The streamflow that resulted from the storm on the Kaibab Plateau caused considerable local scouring and deepening of channels, including some renewed arroyo cutting. The most catastrophic effects of the 1966 floods were caused by two mudflows that extended from the edge of the Kaibab Plateau along Dragon Creek in the Crystal Creek basin and Lava Creek in the Chuar Creek basin to the Colorado River. More than 10 other large mudflows occurred in Nankoweap, Kwagunt, Crystal, and Shinumo Creek basins. About 80 large debris slides left conspicuous scars in the amphitheaters at the heads of the side gorges, and at least 10 small slides occurred on the Kaibab Plateau. (Woodard-USGS)

Professional Paper