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E. R. Hedman

Publications and source records attributed to E. R. Hedman.

7 recordsLinked to original sources
USGS1977

Streamflow characteristics related to channel geometry in the Missouri River basin

The relation of flood-frequency characteristics and mean annual runoff values to active-channel and depositional-bar geometry are presented for six regions in the Missouri River basin. Equations were derived by regression analyses based on the correlation of flow characteristics with the dimensions of the channel geometry. The flow characteristics also were related to the drainage area and a precipitation parameter for comparison. Data for continuous-record gaging stations were used in the derivation. The standard errors for the equations relating either active-channel or depositional-bar widths to mean annual runoff ranged from 26 to 53 percent. The equations relating either active-channel or depositional-bar widths to the flood-frequency discharges of 2, 5, 10, 25, 50, and 100 years had standard errors ranging from 29 to 84 percent.

Alberta, Colorado, Iowa, Kansas, Minnesota, Missou↗
USGS1966

Floods of November and December 1965 in southern California

Severe flooding occurred in southern California in late November and late December 1965 as a result of three heavy storms. Rain occurred on most days during the period November 13-26 and December 28-31, with major amounts distributed in three periods: November 13-19, 21-26, and December 28-31. More than 12 inches of precipitation was reported at Mount Baldy and Big Bear Lake on November 23, 1965; and more than 15 inches was reported at Mount Baldy on December 29, 1965. Peak discharges at streamflow stations were generally the highest since 1943. The Los Angeles River at Sepulveda Dam and the Santa Clara River at the Los Angeles-Ventura County line had peak discharges greater than those of March 1938, the highest previously known. Eleven deaths were attributed to the storm and the resulting floods, and preliminary estimates indicate damage in excess of $11 million in the foothill and valley areas. Flood-control, water-conservation, and power-production reservoirs effected a substantial reduction in the magnitude of the floods in many areas and thus prevented more extensive damage.

California↗