Flow Resistance of High-Gradient Gravel Channels
The flow resistance in terms of the friction factor for bank-full or high in-bank flows for 120 high-gradient gravel-bed rivers are examined. The friction factor f was divided into grain...

Roughness Coefficients for High-Gradient Channels in New York State
Manning's roughness coefficients (n values) were computed for a range of flows at six streams in New York State (USA) that have high energy gradients (greater than 0.002) and large median...

Bias in Regression Estimates of Manning's n
Selected equations for estimating roughness for gravel-bed streams were tested using a composite data set containing much of the data used to define the equations. All equations tested...

Supercritical Flows Versus Subcritical Flows in Natural Channels
Many analysts model large discharges and/or high-gradient reaches as supercritical flow. While this assumption may be valid for man-made channels of smooth, non erosive materials, and...

Flow patterns in a mountain stream
This paper deals with the occurrence of subcritical and supercritical flow, and their related flow patterns. A flow pattern theory was presented by Bathurst et al., (1979), that considers...

Critical and Supercritical Flows in two Unstable, Mountain Rivers, Toutle River System, Washington
Critical and supercritical flows are generally considered to be rare occurrences in natural river channels. This paper presents data and results pertaining to the existence of measured...

Bed Load Roughness in Supercritical Flow
A supercritical concrete channel has been proposed for Mission Creek located in Santa Barbara County, California. The proposed channel could transport gravels and cobbles as bed load during...

Analysis of Levee Design in a Mountain River Using Two-Dimensional Flow Modeling
The South Branch of the Potomac River experienced extreme flooding in November 1985. A flood with an estimated return period of 400 years caused $33 million in damage in Petersburg, West...

Boundary Conditions and Flow Patterns in a Mountain River
Flood flow patterns in mountain valleys may be influenced by longitudinal variations in channel and valley morphology and by temporal variations in boundary conditions. This study utilizes...

Erosion and Deposition by Debris Flows in Mountainous Channels on North Fork Mountain, Eastern West Virginia
A study of four debris-flow impacted channels in the North Fork Mountain area of eastern West Virginia shows that the geomorphic effect of debris flows on channel morphology is variable...

Size Characteristics of Debris Flow Deposition
The size distribution of debris flow deposition is extremely wide which may contain nearly all particles from clay and colloid to boulder. Particle size and composition have very important...

Energy Losses in Steep Tributary Streams at Flows Near The Threshold of Bedload Entrainment
The flow patterns in mountain tributary streams that depends on the channel morphology, cobbles, boulders and debris that protrude along the channel and bank height cause energy losses...

The Transport of Gravels in Boulder-Bed Streams
In boulder-bed streams, gravel is typically found in isolated pockets protected by local flow obstructions. The deposition and entrainment of these gravels depend strongly on the local...

Thresholds for Gravel and Cobble Motion
Flows necessary to initiate motion of rocks on a lateral bar along the Gunnison River in Black Canyon of the Gunnison National Monument are observed. Gravel and cobbles are painted and...

An Approach to the Calculation Method of Mean Sediment Size
Mean sediment size is an important parameter expressing the characteristics of sediment. Several calculation methods of mean sediment size which are popular at present almost have some...

Step-Pool Streams: An Adjustment to Maximum Flow Resistance
An experiment was conducted to study the maximum flow resistance of step pool streams and the morphology of the steps formed from clastic materials. The step pool formation was qualitatively...

A General Theory of Channel Adjustment in High Gradient Streams
The paper presents a theory of channel adjustment in high gradient streams. This theory states that given sufficient energy, stream channels will adjust their dimensions and flow hydraulics...

Step Pool Geometry and Flow Characteristics in Low-Sediment-Storage Channel Beds
Data from two small ephemeral streams in Israel indicate that step pool geometry in bedrock channels is similar, in its salient features, to that in alluvial channels. For steep (>0.10)...

Analysis of blocking phenomena in bifurcated channels found in mountainous rivers
The paper presents an analysis of blocking phenomena in bifurcated channels found in mountain rivers. A change of channels may be caused by deposition of sediments which blocks the entrance...

Estimating Local Bed Shear Stress in Large Gravel-Bed Rivers
The local bed shear stress ?o1 cannot be directly measured and is typically estimated using flow observations in various theoretical or empirical...

 

 

 

 

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