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Oscar G. Lara

Publications and source records attributed to Oscar G. Lara.

5 recordsLinked to original sources
USGS1979

Annual and seasonal low-flow characteristics of Iowa streams

The low-flow characteristics of Iowa streams are described by annual and seasonal low-flow frequency and duration data. Tabulated in this report are low-flow data collected at 135 gaging stations on Iowa streams, three on the Mississippi River, four on the Missour River, and 426 partial-record sites. The information contained in this report is based on all of the daily discharge records collected by the U.S. Geological Survey through the 1976 water year. Consideration is given to the regional aspects of low-flow characteristics by including regression equations to estimate the average discharge and generalized maps to estimate the 7-day, 2-year and 7-day, 10-year discharges at ungaged sites.

Iowa↗
USGS1978

Effects of urban development on the flood-flow characteristics of the Walnut Creek Basin, Des Moines Metropolitan area, Iowa

This report deals with the probable impact of urban development on the magnitude and frequency of flooding in the lower reach of the Walnut creek Basin. Stream-modeling techniques, which include complete definition of unit hydroqraphs and precipitation loss-rate criteria, were utilized to evaluate the effects of urban development as measured by percentages of impervious area over the basin. A mathematical model, called HEC-1, was calibrated by using concurrent rainfall-runoff data collected at three gaging stations in the basin. The model parameters were regionalized to allow future users to estimate the model parameters for ungaged areas within the basin. Long-term rainfall data recorded at two nearby stations were employed as basic input to the calibrated model to generate annual peak discharges corresponding to selected degrees of urbanization. Results are presented in tables and graphs, which compare the pre-urban and urban flood flow characteristics of the lower reach of the Walnut Creek basin.

Iowa↗
USGS1976

Flood of June 27, 1975, in City of Ames, Iowa

On June 27, 1975, the city of Ames and vicinity sustained severe flooding from Squaw creek and the south Skunk River. The storm which preceded the flood was net particularly outstanding in its intensity or duration. However, antecedent conditions plus the timing and direction of the storm were "ideally tuned" to cause the flood. In terms of magnitude of discharge as well as of damages this was the most severe flood on record, with losses estimated by city and Iowa State University officials at over a million dollars. The most unfortunate loss involved the drowning of a young person. The peak discharge at the Squaw Creek station, 206 mi 2 (534 km 2 ), was measured at 11,300 ft 3 /s (320 m 3 /s), which is 1.6 times the 100-year flood. The south Skunk River above the confluence with Squaw creek, 315 mi 2 (816 km 2 ), peaked at 5,330 ft 3 /s (151 m 3 ). The recurrence interval of this discharge is 6.0 years. The peak discharge on the South Skunk River below the confluence with Squaw creek, 556 mi 2 (1440 km 2 ), was 14,700 ft 3 /s (416 m 3 /s), which is 1.1 times the 100-year flood.

Iowa↗