Scour Development at Isolated River-Bed Obstacles
Development of local scour was investigated for isolated obstacles on movable beds subject to clear-water scour. The resulting maximum scour depths, scour volumes, and obstacle displacements...

n Values for Shallow Flow in Rough Channels
Manning's friction factor n has been developed from flume data for very shallow open channel flow in a high-gradient channel with large bed material. n values are presented as a function...

Problems with Numerical Modeling of Gravel-Bed Rivers
Inherent to one-dimensional numerical models are the assumptions that hydraulic parameters can be assigned a characteristic average value, and that the flow is gradually varied so that...

Local Scour at Skewed Bridge Piers
Presented herein are experimental data showing the influence of pier skewness, also referred to as angle of attack, on depth of local scour at rectangular and oblong bridge piers. The...

Supply of Large Woody Debris in a Stream Channel
The amount of large woody debris that potentially could be transported to bridge sites was assessed in the basin of the West Harpeth River in Tennessee in the fall of 1992. The assessment...

The Control and Monitoring of Local Scour at Bridge Piers
A series of flume experiments revealed a possible method of reducing local river bed scour at bridge piers, thereby, reducing the risk of bridge failure. Three prototype schemes were installed...

Calibration of Manning's Roughness for a River Reach
The Albuquerque Projects Office of the U.S. Bureau of Reclamation collected water surface elevations for measured discharges for the Rio Grande and many of its tributaries to try to obtain...

Visualization and Analysis of Multi-Dimensional Velocity Measurements in Carquinez Strait, California
On 11 March, 12 March, 15 April, and 16 April, 1991 the United States Geological Survey (USGS), Sacramento, CA, employed a Downward Looking Acoustic Doppler Current Profiler (DL-ADCP)...

Stratification Models Sensitivity to Solar Radiation Data
A one-dimensional water quality model (WESTEX model) for simulation of thermal stratification is used to test the performance of such models related to hydrometeorological input data....

Low-Flow Habitat in Flood Control Channels
A critical phase in the life cycle of many riverine species in flood control channels is during low-flow periods when the quantity and quality of available habitat diminishes. However,...

The Flushing Flow Problem on the Trinity River, CA
Flushing flows are high flow releases designed to remove fine sediment accumulated in river gravels downstream of reservoirs. These releases must be designed to maximize transport of sand-sized...

Indian River Inlet: Is There a Solution?
Man-made changes at Indian River inlet, Delaware, have occurred over the past 6 decades. During this period the tidal prism of the Indian River-Rehoboth Bays system has increased along...

A Mathematical Model of Flow in Mildly Sinuous, Deep Channels
A mathematical study of flow in deep, weakly-meandering channels has been carried out and formulations for the tangential and radial velocities, valid in conditions have been developed....

Use of Floodplain PCB Concentrations to Calibrate a River Hydraulics Model
A river floodplain was found to contain measurable quantities of polychlorinated biphenyls (PCBs), presumably deposited during historic flood events. A hydraulic model (HEC-2) was used...

Research Needs for Debris Flow Disaster Prevention
A 'soft' disaster reduction strategy is proposed based on identification of hazard location, extent and maximum intensity; monitoring of antecedent catchment moisture, sediment and vegetation...

Debris Flows in Grand Canyon National Park, Arizona: Magnitude, Frequency and Effects on the Colorado River
Debris flows are recurrent sediment-transport processes in 525 tributaries of the Colorado River in Grand Canyon. Arizona. Initiated by slope failures in bedrock and (or) colluvium during...

Fish Screen Developments, Columbia River Dams
This paper describes developments to date for a fish diversion and bypass system being tested for two Columbia River dams. Because of the concern for the negative impacts of screen systems...

Hydraulic Aspects of a Low-Velocity, Inclined Fish Screen
The Potter Valley Hydroelectric Project diverts up to 310 cfs from Van Arsdale Reservoir on the Eel River in north-central California and delivers it to Potter Valley for power production...

A Method of Managing Floating Debris
The device described offers a promising approach to a new method of managing floating debris. It modifies the surface flow of water from a submerged location. The modified flow reduces...

Variations Encountered in Design Analysis of Local Scour at Drop Structures
Proper design of drop structures can prevent failure due to scour at upstream structures, like bridges. An important aspect of drop-structure design is the prediction of the local scour...

 

 

 

 

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