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...
Assessment and Prediction of Debris-flow Hazards
Study of debris-flow geomorphology and initiation mechanism has led to better understanding of debris-flow processes. This paper reviews how this understanding is used in current techniques...
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...
Debris Flows and Mass Wasting in Volcanic Torrents
Observation of debris flow and topographic survey for mass wasting in the volcanic torrents clarified that (1) mass wasting processes such as rock fall from the side-wall and toppling...
Interpreting Debris-Flow Hazard from Study of Fan Morphology
The deposits, stratigraphy, and surface morphology of debris-flow fans are a record of past debris-flow activity, and as such can provide useful information about debris-flow hazards....
Hydraulic Modeling of Fish Screens
Hydraulic model studies coupled with available knowledge of fish behavior can be important component in the development of fish-screening systems. To reproduce in a model the flow field...
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...
Ask Young Clupeids if Kaplan Turbines are Revolving Doors or Blenders
Previous estimates of low survival (18 to 38 %) of young clupeids (American shad, blueback herring, and alewife) in passage through hydro turbines have led many to conclude that turbines...
Regulation of Flow Downstream of Weirs
Reregulation weirs are one means adopted by the Tennessee Valley Authority (TVA) to provide continuous improved minimum flow and wetted area for aquatic life downstream if hydroprojects...
Flow Resistance Properties of Flexible Linings
Flow resistance for flexible channel linings is a function of the relative roughness of the lining in accordance with boundary-layer principles. As with vegetation, flexible linings have...
Storm Drainage Channel Rehabilitation
30 km (19 miles) of existing concrete lines storm drainage channels were studied due to repeated failures. Alternate failures causes were hypothesized and evaluated. Physical testing was...
Determination of Hydraulic Roughness for Concrete-Lined, Supercritical Channels
A channel verification program has been initiated by the US Army Engineer District, Los Angeles to determine the hydraulic roughness of flow in a concrete channel. Specifically, this study...
Cable-tied Concrete Block Erosion Protection
An articulated concrete erosion protection system is investigated as a possible revetment for bridge piers to be used in place of the traditional rip-rap revetment. The system consists...
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...
The Influence of Protective Material on Local Scour Dimensions
Protective materials installed around the base of a bridge pier can reduce or prevent local scour. The performance of four materials: grout mats, grout bags, footings, and riprap, are...
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...
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