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...
Survival of Atlantic Salmon Smolts Bypassed Through Ice-Log Sluices Determined by the HI-Z Turb'N Tag
The HI-Z Turb'N Tag was used to assess injury and mortality incurred by Atlantic Salmon (Salmo salar) smolts bypassed through ice-log sluiceways at two stations. Both sluiceways were similar...
Tetrapods as a Scour Countermeasure
Few materials have been studied for their effectiveness in protecting bridge piers and abutments from local scour other than riprap. Recent research conducted at the FHWA research facility...
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...
Threats to Bridge Stability from Scour Related Failures of Drop Structures
Catastrophic failure of bridge foundations may occur when channel bed elevations are lowered unexpectedly. Bridges to be constructed in channels that are known to have bed degradation...
Mechanics of Debris Flows
The paper deals with the mechanics aspects of the modelling of debris flows and will focus on steady, fully developed flows. After a brief review of the types of constitutive equations...
Kenetic-theory Approach to the Nevado Del Ruiz 1985 Debris Flow
The Nevado del Ruiz 1985 debris flow was the worst disaster of its kind in this century, killing 22,000 people. By making an idealization of the debris flow material and the flow regime,...
Continuum-Mechanics-Based Rheological Formulation for Debris Flow
This paper aims to assess the validity of the generalized viscoplastic fluid (GVF) model in the light of both the classical relative-viscosity versus concentration relation and the dimensionless...
Modeling Low Flow Transport of Nonconservative Pollutants in Streams
The complex nature of low flow transport and transformation of nonconservative pollutants in natural streams has been investigated using a numerical solution of a proposed mathematical...
Repeatability and Oblique Flow Response Characteristics of Current Meters
Laboratory investigation into the precision and accuracy of various mechanical-current meters are presented. Horizontal-axis and vertical-axis meters that are used for the measurement...
Bed Shear Stress in Unsteady Open-Channel Flows
In this study, velocity distributions over smooth and rough beds were accurately measured with an LDA in unsteady open-channel flows. The log-law distributions yielded well in the wall...
Limitations of Reduced Scale Testing on Parshall Flumes
A model for the boundary layer development in the entrance section of a Parshall flume is developed to account for the effects of fluid viscosity on flume calibration equations. Data for...
Water-Level, Velocity, and Dye Measurements in the Chicago Tunnels
On April 13, 1992, a section of a 100-year-old underground freight tunnel in downtown Chicago, Illinois was breached where the tunnel crosses under the Chicago River, about 15 meters below...
Prediction of Gravel Transport Using Parker's Algorithm
This paper demonstrates that sediment discharge in gravel streams can be reasonably estimated by calibrating the Parker and Klingeman procedure. This paper also identifies the need for...
Emergent Techniques in Scour Monitoring Devices
This paper presents a brief status report of a research and development project funded by the National Cooperative Highway Research Program (NCHRP) to develop and test scour monitoring...
Riprap Design at Bridges?Factor of Safety Approach
The factor of safety method offers a physically based methodology for design of riprap that relates the applied shear stress on the channel boundary to the stability of the riprap layer....
Riprap Incipient Motion and Shields' Parameter
Unobstructed incipient motion data from a variety of sources are compiled to re-examine current thinking regarding riprap stability. Shields' framework is investigated and relationships...
Roll Waves in Mud Flow
Permanent roll waves on a shallow layer of fluid mud which is modeled as a power-law fluid is studied. Based on long-wave approximation, momentum integral method is applied to derive the...
Friction in Debris Flows: Inferences from Large-scale Flume Experiments
A recently constructed flume, 95 m long and 2 m wide, permits systematic experimentation with unsteady, nonuniform flows of poorly sorted geological debris. Preliminary experiments with...
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