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S. E. Rantz

Publications and source records attributed to S. E. Rantz.

At least 19 recordsLinked to original sources

Adjustment of logarithmic flood-frequency statistics for gaged California streams to minimize the time sampling error

Methods for adjusting logarithmic flood-frequency statistics for gaged streams to minimize the time sampling error that is inherent in short records are discussed. Statistical procedures for adjusting the mean and standard deviation of a short-term array of annual peak discharges are already well established; two standard sets of equations for utilizing the additional information contained in longer records of peak discharge observed at nearby gaging stations are given. A standard method for adjusting the coefficient of skew does not exist, and consequently a special technique for estimating the long-term value of that statistic was developed for this study. Regional equations were developed that relate the logarithmic skew coefficient to logarithmic transformations of mean annual basinwide precipitation and mean annual peak discharge per square mile. The technique appears to be satisfactory for use in the greater part of California, where over large areas the peak discharge in any year is usually associated with a single widespread general storm or with a series of such storms where snowmelt runoff is involved rather than with localized precipitation events.

Journal of Research of the U.S. Geological Survey

Application of the source-area concept of storm runoff to a small Arizona watershed

An attempt to demonstrate the source-area concept of storm runoff by analysis of the rainfall-runoff relation for the watershed of Queen Creek tributary in south-central Arizona was moderately successful. The demonstration was somewhat marred by the necessity to make several simplifying assumptions to eliminate some of the many basin variables of unknown magnitude. The percentage of watershed contributing storm runoff was related to total rainfall received that is, antecedent and storm rainfall on the assumption that the availability of rainfall excess from any subarea was dependent on the saturation, or near saturation, of a permeable upper layer of soil. An average unit hydrograph was used for all computed sizes of the runoff-contributing area.

Arizona

Mean annual precipitation and precipitation depth-duration-frequency data for the San Francisco Bay region, California

This report presents precipitation data for the San Francisco Bay region in a form suitable for use as criteria for both drainage design and the study of the stability of land slopes. The data presented include (1) an isohyetal map showing long-term mean annual precipitation and (2) a table of storm precipitation depths, corresponding to various durations and frequencies, that are applicable to any site in the region. The regimen of precipitation in the region is such that depth-duration frequency characteristics for a site are closely related to the mean annual precipitation for that site.

California

A summary of methods for the collection and analysis of basic hydrologic data for arid regions

This report summarizes and discusses current methods of collecting and analyzing the data required for a study of the basic hydrology of arid regions. The fundamental principles behind these methods are no different than those that apply to studies of humid regions, but in arid regions the infrequent occurrence of precipitation, the great variability of the many hydrologic elements, and the inaccessibility of most basins usually make it economically infeasible to use conventional levels of instrumentation. Because of these economic considerations hydrologic studies in arid regions have been commonly of the reconnaissance type; the more costly detailed studies are generally restricted to experimental basins and to those basins that now have major economic significance. A thorough search of the literature and personal communication with workers in the field of arid-land hydrology provided the basis for this summary of methods used in both reconnaissance and detailed hydrologic studies. The conclusions reached from a consideration of previously reported methods are interspersed in this report where appropriate.

Open-File Report

Urban sprawl and flooding in southern California

The floods of January 1969 in south-coastal California provide a timely example of the effect of urban sprawl on flood damage. Despite recordbreaking, or near recordbreaking, stream discharges, damage was minimal in the older developed areas that are protected against inundation and debris damage by carefully planned flood-control facilities, including debris basins and flood-conveyance channels. By contrast, heavy damage occurred in areas of more recent urban sprawl, where the hazards of inundation and debris or landslide damage have not been taken into consideration, and where the improvement and development of drainage or flood-control facilities have not kept pace with expanding urbanization.

Circular

Hydrologic reconnaissance of Point Reyes National Seashore area, California

This report summarizes the results of a hydrologic reconnaissance of the Point Reyes National Seashore area, the primary purpose of which was to appraise potential sources of water supply at park sites where visitor accommodations are proposed. Point Reyes National Seashore is a peninsular area on the California coast about 50miles north of San Francisco. Inverness Ridge, with peaks about 1,400 feet above sea level, forms the eastern boundary of the seashore. Marine terraces, extending from sea level to altitudes of about 400 feet, form the remainder of the area.

Open-File Report

Effect of urban growth on streamflow regimen of Permanente Creek, Santa Clara County, California

This report presents the results of an investigation of the effect of urban growth on the streamflow regimen of Permanente Creek in Mountain View, Santa Clara County, Calif. The data available did not permit a complete study of all hydrologic aspects, but there is conclusive evidence that the volume of storm runoff produced by rainfall on the valley floor has increased substantially as a result of urbanization. In 1945, storm runoff from the 5.12-square mile project area was insufficient to balance channel losses, and the streamflow entering the project area in the Permanente Creek channel was greater than that leaving the area. If, however, total outflow from the project area is considered to be the sum of the streamflow leaving the area plus channel seepage in the area, the ratio of total outflow to inflow was 1:18. By 1958, storm runoff from the project area was far in excess of channel losses and the ratio of total outflow to inflow was 1:70. This increase in outflow is attributed to the fact that urban development during the period 1945 to 1958 increased the extent of impervious surface in the project area from about 4 percent to 19 percent. The effect of urban growth in other basins in Santa Clara County should be investigated before any attempt is made to project the quantitative results of this study to other areas in the county.

Water Supply Paper

Floods of January-February 1963 in California and Nevada

Widespread flooding occurred in central California and northwestern Nevada during January 31 - February 1, 1963, as a result of intense precipitation of about 72 hours duration. The flood-producing storm was of the warm type, with precipitation falling as rain at altitudes as high as 8,000 feet. The heavy precipitation, totaling as much as 20 inches or more in the Sierra Nevada, fell on frozen ground or on the sparse snowpack that existed in the higher altitudes. The response of runoff to rainfall was dramatic, as streams throughout the area rose rapidly. Hardest hit were the basins of the American, Yuba, and Truckee Rivers, where flood peaks either reached record-breaking heights or rivalled the discharges attained in the memorable floods of November 1950 and December 1955. Because of the relatively short duration of the storm, the volume of flood flow in 1963 was not outstanding. Ten deaths were attributed to the storm or flood. Preliminary estimates indicate damage in excess of $16 million in foothill and valley areas, but no attempt has yet been made to assess the heavy damage to highways and drainage structures in the mountain areas. The U. S. Army, Corps of Engineirs estimates that its operation of flood-control facilities prevented additional damage of $236 million. Other reservoirs, operated primarily for water conservation or power production, were also instrumental in preventing damage.

California;Nevada