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Harlan H. Schwob

Publications and source records attributed to Harlan H. Schwob.

9 recordsLinked to original sources
USGS1971

Floods in the Wapsipinicon River Basin, Iowa

Flood information is reported for 338 miles of the main stem and six tributaries of the Wapsipinicon River. The information will be of use to those concerned with the design of bridges and other structures and the conduct of various operations on the flood plains of the streams. Included in the report are flood-peak records, gaging-station records, frequency curves, and water-surface profiles. Outstanding floods resulting from extremely heavy rainfall occurred in the upper basin in 1968 and 1969. Those in 1968 produced the highest flood of record at the gaging station at Independence. The flood of 26,800 cfs (cubic feet per second) at this station was the greatest in the period 1933-70. A number of the smaller tributaries experienced floods more than five times the computed 50-year flood. The flood experience on the main stem downstream from Anamosa has not been outstanding. No flood of record has exceeded the 50-year flood in this reach. Flood-profile sheets show profiles of actual flood occurrences and computed profiles of the 25- and 50-year floods at most locations. These sheets also contain tabulations of the flood discharges profiled. A low-water profile and tabulated discharge indicate the range in elevation and discharge along the streams.

Iowa, Minnesota↗
USGS1970

Flood profile study, Morgan Creek, Linn County, Iowa

The purpose of this report is to present the results of a study made for a 35,000-foot reach of Morgan Creek. The report shows profiles computed for a large flood under existing conditions and for a smaller flood for two assumed conditions of encroachment. Flood-plain management can benefit from this type of information during future expansion of the urban area. This report is a result of a cooperative agreement between the City of Cedar Rapids and the U.S. Geological Survey that provides for the collection and analysis of flood data in, and near, the City of Cedar Rapids.

Iowa↗
USGS1970

Floods of April-May 1969 in upper Midwestern United States

The 1969 spring floods in upper Midwestern United States can be attributed primarily to an exceptionally heavy blanket of snow which accumulated during the period December 1968 through February 1969. March precipitation was light, but at the end of the month water content of snow on the ground was as much as 8 inches in some parts of the area. Unusually heavy rains in the fall of 1968 throughout the area, and as much as 3 inches of localized spring rain in the Red River basin during the period April 7-10, 1969, accentuated the flooding. Flood data are presented for 285 gaging sites in this report. Peak stages and discharges exceeded previous known maxima in the upstream tributaries of the Red River of the North, upper Minnesota River basin, upper basin of West Fork Des Moines River, and the James, Vermillion, and Big Sioux River basins. In many other basins the 1969 floods were the second highest in many years of record. Recurrence intervals exceeded 50 years for 71 of the 178 sites for which recurrence intervals were computed. Flood-crest elevations and flood profiles show the peak stages expressed in mean sea level at many points in the Mississippi, Minnesota, Red, Souris, West Fork Des Moines, Rock, and Little Rock River basins. Sediment discharge data obtained in a small part of the lower Minnesota River basin indicated varying yields during the month of April ranging from 26 to 396 tons per square mile. Aerial photography during the flood was obtained in a number of river basins. The river reaches which were photographed are tabulated and the location of the photographs indicated. Flood damages were estimated to be about $147 million in the six States of North Dakota, South Dakota, Minnesota, Iowa, Wisconsin, and Illinois. Eleven lives were lost to the flood, more than 23,000 persons were forced from their homes, more than a million acres of rich agricultural land were inundated, and thousands of culverts and bridges were washed out on highways and secondary roads.

Illinois, Iowa, Minnesota, North Dakota, South Dak↗
USGS1968

Flood of June 7, 1967, in the Wapsinonoc Creek Basin, Iowa

An outstanding flood occurred in the Wapsinonoc Creek basin in east-central Iowa on June 7, 1967. The flood was the result of rainfall totaling from 4 to 13 inches in about 14 hours on the night of June 6 and the morning of June 7. The storm was nearly centered over the 180·square mile basin. The resulting peak discharges ranged from about 1.9 to about 4.3 times the 50-year recurrence interval flood. A peak discharge of 27,400 cubic feet per second was measured from 161 square miles of the basin. This and other peak discharges for drainage areas larger than 40 square miles were among the greatest recorded in the last 50 years in eastern Iowa. Flood damage was light because the basin is used primarily for agriculture and the crops were in their early growth stage. 'There was no loss of human life attributed to the flood.

Iowa↗
USGS1966

Magnitude and frequency of Iowa floods, Part two

Flood records for regular and partial-record gaging stations are contained in the following pages. Each listing contains the station number and name, descriptive paragraphs pertaining to the station, and a listing of the flood peaks available through the 1965 water year. Peaks above a base as well as annual peaks are listed. These provide the data for a partial-duration flood-frequency curve. Most of the material is self-explanatory and needs no discussion. However, a few items may be made clearer by the brief explanation which follows.

Iowa↗
USGS1966

Magnitude and frequency of Iowa floods, part one

Iowa stream-gaging station records at 147 regular gaging stations and partial-record sites were analyzed to produce flood magnitude and frequency relations. An index flood which is the mean annual flood and two composite frequency curves are used to predict the flood-frequency curve for interior streams of the State. The index flood was determined by a multiple correlation. The independent variables found to be significant are size of drainage basin, stream slope, and the normal annual precipitation for the 1931–60 period. The regression equations for two areas were determined—a large central area and a combination of areas in the northeastern and southwestern parts of the State. All three independent variables were used in the central area. Only area and slope were found necessary in the remainder of the State. The ratio to the index flood at selected recurrence intervals was determined from each of the gaging-station flood-frequency curves. The median of the ratios for the long term period (1916–65) is used to define the two composite curves. Maximum flood discharges at gaging stations and miscellaneous sites are tabulated and related to their frequency of occurrence. Together with the analysis previously described they form part one of a two part report. Basic data in the form of flood peak stages and discharges for each year of record at each gaging station are published in part two of the report.

Iowa↗
USGS1965

The 1965 Mississippi River flood in Iowa

The great flood of 1965 on the Mississippi River, along the eastern border if the State, exceeded any flood known in 139 years. It cause damages probably in excess of ten millions of dollars in the State of Iowa. Studied now in progress will more thoroughly cover this and other phases of the flood. The underlying cause of the flood was an abnormally cold winter which prevented the melting of an excessive snow cover in the upper reaches of the basin. Heavy rains late in March followed by rapid melting triggered the runoff which caused the floods. Peak discharges experienced ranged from 276,000 cfs (cubic feet per second) at McGregor near the northern boundary of the State to 327,000 cfs at Keokuk near the southern boundary. Tributary streams in Iowa were receding as the main-stem flood peak passed their mouths. The discharge they contributed was generally insignificant except for the larger streams. Flood data compiled for the part of the River along the eastern border include flood discharges, flood elevations, and the frequency of floods of varying magnitudes. They also include the daily or more frequent stage and discharge data for both the Mississippi River and the downstream gaging stations on Iowa tributaries for the period March-May 1965. Sufficient data are presented to permit studied for preparation of plans for protective works and plans for zoning or for flood plain regulation.

Illinois, Iowa, Wisconsin↗