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Robert W. Meyer

Publications and source records attributed to Robert W. Meyer.

6 recordsLinked to original sources

Geological, hydrological, and biological issues related to the proposed development of a park at the confluence of the Los Angeles River and the Arroyo Seco, Los Angeles County, California

A new park is being considered for the confluence of the Los Angeles River and the Arroyo Seco in Los Angeles County, California. Components of the park development may include creation of a temporary lake on the Los Angeles River, removal of channel lining along part of the Arroyo Seco, restoration of native plants, creation of walking paths, and building of facilities such as a boat ramp and a visitor center. This report, prepared in cooperation with the Mountains Recreation and Conservancy Authority, delineates the geological, hydrological, and biological issues that may have an impact on the park development or result from development at the confluence, and identifies a set a tasks to help address these science issues. Geologic issues of concern relate to surface faulting, earthquake ground motions, liquefaction, landsliding, and induced seismicity. Hydrologic issues of concern relate to the hydraulics and water quality of both surface water and ground water. Biological issues of concern include colonization-extinction dynamics, wildlife corridors, wildlife reintroduction, non-native species, ecotoxicology, and restoration of local habitat and ecology. Potential tasks include (1) basic data collection and follow-up monitoring, and (2) statistical and probabilistic analyses and simulation modeling of the seismic, hydraulic, and ecological processes that may have the greatest impact on the park. The science issues and associated tasks delineated for the proposed confluence park will also have transfer value for river restoration in other urban settings.

Scientific Investigations Report

Flood-prone areas and waterways, Edwards Air Force Base, California

Edwards Air Force Base (EAFB) is in the Mojave Desert region of southern California. Although the climate in the study area is arid, occasional intense storms result in flooding on the base, damaging roads and buildings. To plan for anticipated development at EAFB, the U.S. Department of the Air Force (USAF) and the U.S. Geological Survey (USGS) began a cooperative study to locate flood-prone areas on the base. This report describes flood hazards and shows flood-prone areas of the base.

Open-File Report

Assessment of peak discharge uncertainty in the American River basin, California

Flood-discharge data, current-meter and indirect measurements, and stage-discharge relations, the oldest of which dates to the early 1900's, were used to estimate the uncertainty about annual flood peaks in or near the American River Basin at 20 stream-gaging stations operated by the U.S. Geological Survey. The study estimates that, in the study area, most flood peaks that were determined from current-meter measurements have an uncertainty of about plus or minus 3 percent, whereas the peaks that were determined from indirect measurements have an uncertainty ranging from plus or minus 10 to plus or minus 70 percent. The study also determined that the stage-discharge relations that have been developed for most of the sites in the American River Basin are correct.

Open-File Report

Magnitude and frequency of the floods of January 1997 in northern and central California; preliminary determinations

Preliminary determinations of the magnitude and frequency of peak flows resulting from the storms of December 1996 and January 1997 were made at 292 streamflow gaging stations located in 45 counties in northern and central California. Peak flows were the largest on record at 106 stations, and recurrence intervals were greater than 100 years at 32 stations. Two separate frequencies were determined for the 1997 peak flow at each streamflow station: a frequency based on an analysis that includes annual peak flows through the 1996 water year (ending September 30, 1996) and a frequency based on an analysis that includes the 1997 peak.

Open-File Report

Potential hazards from flood in part of the Chalone Creek and Bear Valley drainage basins, Pinnacles National Monument, California

Areas of Chalone Creek and Bear Valley drainage basins in Pinnacles National Monument, California, are subject to frontal storms that can cause major flooding from November to April in areas designated for public use. To enhance visitor safety and to protect cultural and natural resources, the U.S. Geological Survey in cooperation with the National Park Service studied flood-hazard potentials within the boundaries of the Pinnacles National Monument. This study area extends from about a quarter of a mile north of Chalone Creek Campground to the mouth of Bear Valley and from the east monument entrance to Chalone Creek. Historical data of precipitation and floodflow within the monument area are sparse to nonexistent, therefore, U.S. Soil Conservation Service unit-hydrograph procedures were used to determine the magnitude of a 100-year flood. Because of a lack of specific storm-rainfall data, a simulated storm was applied to the basins using a digital-computer model developed by the Soil Conservation Service. A graphical relation was used to define the regionally based maximum flood for Chalone Creek and Bear Valley. Water-surface elevations and inundation areas were determined using a conventional step-backwater program. Flood-zone boundaries were derived from the computed water-surface elevations. The 100-year flood plain for both streams would be inundated at all points by the regional maximum flood. Most of the buildings and proposed building sites in the monument area are above the elevation of the 100-year flood, except the proposed building sites near the horse corral and the east monument entrance. The 100-year flood may cause reverse flow through a 12-inch culvert embedded in the embankment of Old Pinnacles Campground Road in the center of Chalone Creek Campground. The likelihood of this occurring is dependant upon the amount of aggradation that occurs upstream; therefore, the campground area also is considered to be within the 100-year flood zone.

Open-File Report