Comparison of Design Rainfall Criteria for the Southwest
The design of drainage and flood control facilities or the management of floodplains for alluvial fans is extremely sensitive to the design rainfall criteria that is used as input to the...
Inclusion of Wetlands in Designated Floodway Studies
The purpose of this paper is to propose a change in the traditional methods and procedures used by hydrologist and hydraulic engineers to define floodways and floodway fringe areas. We...
Two-Dimensional Modeling of Alluvial Fan Flows
A two-dimensional, flood routing model FLO-2D has been developed to route water and mudflows over unconfined surfaces. It predicts flow velocities and depths at discrete points for channel...
Flood Hazard Delineation on Alluvial Fans
Alluvial fans are significant geomorphic features of arid lands. The unconfined and dynamic nature of alluvial fans makes standard methods of delineating flood hazards unsuitable. The...
Application of the U.S.G.S. DHM for Floodplain Analysis
The two-dimensional Diffusion Hydrodynamic Model, DHM, is applied to the evaluation of floodplain depths resulting from an overflow of a leveed river. The environmental concerns of flood...
Phoenix Flood Hydrology for Price Expressway
Recently HDR Engineering, Inc. (HDR) completed a study of the off-site stormwater volumes and peak flow rates for the Price Expressway and Santan Freeway in suburban Phoenix. HDR is the...
Multi-Date Image Analyses Used for Determining Flood Area Impacts in the Saginaw River Basin, Michigan
During the months of September and October 1986, a series of storms swept across the Lower Peninsula of Michigan. These heavy downpours caused $400 million worth of flood damages. Significant...
Remote Sensing of Rainfall with NEXRAD
In utilizing the Next Generation Weather Radar (NEXRAD) for remote sensing of rainfall, three stages of precipitation processing have been developed by the National Weather Service's...
Transmission Losses, Flood Peaks, and Groundwater Recharge
Abstractions of streamflow in ephemeral stream channels from infiltration in the channel beds and banks are called transmission losses. These losses are important because water is 'lost'...
Piedmont-Fan Flood Hazard Analysis From Geomorphology and Surface Water Hydrology, Hudspeth County, Texas
A 2-mi2 (5.2 km2) site selected by the Texas Low-Level Radioactive Waste Disposal Authority was technically...
Large Floods and Climate Change in the Southwestern United States
Floods can have a tremendous impact on water resources but their properties may fluctuate at frequencies that defy recognition in short-term instrumented records. Paleoflood deposits provide...
Misapplication of the FEMA Alluvial Fan Model: A Case History
The Federal Emergency Management Agency (FEMA) recently issued revised Flood Insurance Rate Maps (FIRM) for the Tortolita piedmont, located northwest of Tucson, Arizona. Floodplain delineations...
Channel-changing Processes on the Santa Cruz River, Pima County, Arizona, 1936-86
Lateral channel change on the mainly ephemeral Santa Cruz River, Pima County, Arizona, causes damage and has spawned costly efforts to control bank erosion. Aerial photographs, historical...
Predicting Stream Width and Bank Retreat
The width of streams is dependent on the flood flow discharge which varies from year to year, the bank material which varies from stream to stream and reach to reach, the sediment load...
Alignment of Large Flood-Peaks on Arid Watersheds
Bridge and culvert design requires estimates for 25- to 100-year return period flood peaks (Q). Floodplain delineation calls for 500-year (Q500) estimates. Arid western flood series are...
Regional Flood-Frequency Relations for Streams with Many Years of No Flow
In the southwestern United States, flood-frequency relations for streams that drain small arid basins are difficult to estimate, largely because of the extreme temporal and spatial variability...
Cyclic Streamflow Test for Validity of Randomness
Long-term Arizona runoff records used for flood insurance frequency analysis estimates are compared with long-term precipitation station records for cyclic behavior. Runoff cumulative...
Regional Flood Frequency Equations for Antelope Valley in Kern County, California
Rapid residential, commercial, and industrial development has occurred in recent years in the Antelope Valley, California. With the new development progressing at full speed, the local...
Graphical Verification of Flood Frequency Analysis
In the analysis of flood frequency data, a proper distribution must be chosen to fit the data being analyzed. A properly applied distribution can minimize errors in the extrapolation of...
Multiple Phenomena of Debris-Flow Processes: A Challenge for Hazard Assessments
Hazardous hydraulic processes associated with arid environments commonly repesent significant risks to the safety of the public. However, the public generally considers these risks to...
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