Water-Supply Paper 2502

Summary of Significant Floods in the United States, Puerto Rico, and the Virgin Islands, 1970 Through 1989

Summary of Significant Floods, 1970 Through 1989, by Year

This section includes brief descriptions of selected signficant interstate and intra-state floods in yearly accounts. Floods described in this section were those with excessive loss of life, excessive damage, extreme discharge or gage height, or those regional in extent. References are provided for these as well as other selected significant floods that occurred during the year. Figures 3-22 in this section depict widespread regional flooding by giving the percentage of streamflow-gaging stations in each State or territory recording greater than the approximate 20-year recurrence-interval flooding during the calendar year.

1983

The first significant floods of 1983 occurred in California (fig. 16). Severe storms originating in the Pacific Ocean frequently hit California from January through March. Landslides were the most damaging aspect of the storms, but floods played an important part as well. On January 22 through January 29, a series of intense storms moved rapidly through the northeastern Pacific Ocean and struck the California coast with intense rains, gale-force winds, high surf, and high tides. Riverine flooding from these storms in the San Francisco Bay area produced record flooding.

Severe thunderstorms originating along the central coast of the Gulf of Mexico produced flood conditions for Louisiana and Mississippi on April 5. Rainfall was especially excessive over the Pearl River Basin in Louisiana. The Pearl River crested above flood stage through most of its length on April 7 and stayed above flood stage through the end of April. In southern Mississippi, 8 to 14 in. of rain fell on April 5 (National Oceanic and Atmospheric Adminstration, 1983), and many creeks and rivers in this region experienced maximums of record. Additional rains on April 6 caused severe flooding on Gordon Creek and the Bouie River.

Intense rainfall on April 28 through April 30 produced widespread flooding throughout Kentucky, but the most severe flooding was concentrated in the western part of the State. The rains and flooding lasted through May 4. Rainfall averaged 6 to 10 in. across most of the State (National Oceanic and Atmospheric Administration, 1983). Small streams began flooding April 30, and by May 4, larger streams also had reached flood stage.

The winter of 1982-83 was among the most severe in Wyoming, Colorado, Utah, Nevada, and parts of other Western States since records began. Wet, cold weather with large accumulations of snow continued through April. A record snowpack resulted from the extended winter weather and lingered until May or early June. Temperatures stayed cold longer than normal and when they began to rise, it was a sharp and rapid increase. Several events resulted from these conditions-(1) High-magnitude streamflow, both in terms of volume and maximum discharges, occurred in most of these Western States; (2) the first required use of spillways at Hoover and Glen Canyon Dams on the Colorado River; (3) long-duration flooding along the lower Colorado River; (4) devastating landslides and debris flows in Utah and Nevada; and (5) the highest water level since 1924 in the Great Salt Lake.

Significant floods occurred in southeastern Arizona from September 27 to October 3. The floods were caused by the remnant moisture from dissipating Tropical Storm Octave. The most intense rainfall was concentrated in a narrow band from south of Tucson to Clifton. Large, flat areas northwest of Tucson were inundated with floodwaters when the Santa Cruz and Gila Rivers overtopped their banks and spread across the flood plain.

Significant floods on October 17-23 occurred in southwestern and central Oklahoma. The floods were caused by remnant moisture from Hurricane Tico. The most intense rainfall was concentrated in a narrow band from Rush Springs to Shawnee. Record maximum discharges were recorded on Deep Red Run, the lower Washita River, and Elk and Walnut Creeks. Damages were estimated at $12 million (Paulson and others, 1991).

Selected References for 1983